Program Detail

The 2014 International Workshop on Antenna Technology
(iWAT2014)
Technical Program

Time Ballroom 3 Atrium Foyer

Tuesday, March 4

08:00     Registration Open
08:45 Opening Ceremony    
08:55 Keynotes    
10:20     Coffee Break
10:50 Dual Polarized and Small Antennas    
12:30     Lunch
13:30   Wearable Antennas/BAN,
Millimeter-Wave Antennas and Components,
Reconfigurable & Switchable Antennas,
Arrays
 
15:00     Coffee Break
15:30 New Materials and Composites for Antenna Applications    
18:00   Welcome Reception
 - Sponsored by Leap Australia
 

Wednesday, March 5

08:00     Registration Open
08:20 Arrays, MIMO, Beamforming and Indoor Propagation    
10:20     Coffee Break
10:50 Reconfigurable Antennas    
12:30     Lunch
13:30   Biomedical Applications,
FSS, EBG, Reflect-Arrays & Meta-Surfaces,
Multi-Band Antennas,
Wireless Systems
 
15:00     Coffee Break
15:30 Metamaterials and EBGs    
19:00 Conference Banquet - (Harbour Ballroom, King Street, Wharf 2)

Thursday, March 6

08:00     Registration Open
08:20 Millimeter-wave, THz and Optical Antennas    
10:20     Coffee Break
10:50 Wearable Antennas and Biomedical Applications    
12:50     Lunch
13:45   Wideband and UWB Antennas,
Metmaterial-Inspired & Miniaturized Antennas,
Modelling and Simulation
 
15:30     Coffee Break
16:00 Debate - The Future of Metamaterial Antennas    
17:15 Closing Ceremony    

Tuesday, March 4

08:00 - 08:45

Registration Open

08:45 - 08:55

Opening Ceremony

Chair: Y Jay Guo (CSIRO, Australia)

08:55 - 10:20

Keynotes

Chair: Y Jay Guo (CSIRO, Australia)
08:55 Wireless Research for Australia's Defence
Alexander Zelinsky (DSTO, Australia)
The keynote presentation discusses Wireless Research for Australia's Defence.
09:23 Recent Research on Antennas for Wireless in Australia
Trevor S. Bird (Antengenuity & CSIRO, Australia)
Wireless research has had a long history in Australia initially driven by the need for communication with the outside world. Prior to Federation, the Australian states relied heavily on the overland telegraph connection through Darwin. In 1912 the Applecross wireless station commenced operation with the objective of long range communications. Early work on antennas for wireless was conducted by George Fisk. In the 1920s AWA devised long wire antennas for radio systems for a series of transmissions to Britain and also Alfred Traeger developed the pedal wireless that employed portable antennas for the Royal Flying doctor service. Since then Australia has been involved in research on antennas for radar, astronomy and communications. Some examples include a lightweight, portable air-warning radar system (LW/AW Mk I) with associated grid reflector in the 1940s, corrugated horn antennas for the Parkes radiotelescope in the 1960s, and integrated antennas for an indoor wireless system operating at 60GHz in the 1990s. <br><br> This paper reviews some of the history of antenna research in Australia for wireless particularly for applications in telecommunications and radio astronomy. In addition, it describes recent antenna research undertaken at five Australian universities, CSIRO and DSTO.
09:51 Metamaterial Antennas:From Physics To Designs
Zhi Ning Chen (National University of Singapore & Institute for Infocomm Research, Singapore)
This talk introduces the translational applications of scientific concept of metamaterials in antenna engineering for enhancing the performance and reducing the volume. First, the generalization of the definition of metamaterials in terms of relative permittivity and permeability is discussed from an engineering point of view. Based on the understanding of the metamaterials, several powerful antenna technologies have been developed and applied in practical designs. Then, the innovative metamaterials-based antennas are exemplified. The progress in the development of metamaterials-based antenna has showed us a promising future of metamaterials in engineering.

10:20 - 10:50

Coffee Break

10:50 - 12:30

Dual Polarized and Small Antennas

Chair: Keizo Cho (Chiba Institute of Technology, Japan)
10:50 Non-Foster Augmentations of Electrically Small Antennas: Practical Design Considerations and Results
Richard W. Ziolkowski (University of Arizona, USA)
A review of recent efforts in which an electrically small, near field resonant parasitic antenna is augmented with internal non-Foster circuit elements will be given. Both electric and magnetic electrically small antennas will be discussed. It will explained why different types of non-Foster elements are required for them. It also will be demonstrated that one can combine these designs to achieve an electrically small antenna that has high efficiency; broad impedance and directivity bandwidths; high directivity and a high front-to-back-ratios.
11:10 Applications of Circularly Polarized Crossed Dipole Antennas
Ikmo Park (Ajou University, Korea); Son Xuat Ta (Ajou University, Korea); Jea Jin Han (Ajou University, Korea); Richard W. Ziolkowski (University of Arizona, USA)
Circularly polarized crossed dipole antennas are presented in this paper. A compact crossed dipole is realized with the use of a meander line and a barbed end in each dipole arm. A vacant-quarter printed ring is used as a 90o phase delay line to achieve circularly polarized radiation. For multi-band applications, each dipole arm is divided into multi-branches with different lengths to obtain multiple resonances. These radiators can be equipped with different reflectors, such as a finite planar metallic conductor, a cavity-backed metallic conductor, and a finite artificial magnetic conductor to obtain the desired antenna radiation characteristics. These antennas are quite practical for many wireless communication systems, such as satellite communications, global positioning systems, wireless local area networks, and radio-frequency identification devices.
11:30 Design of Base-Station Antennas with Stable Radiation Patterns
Qing-Xin Chu (South China University of Technology, P.R. China); Yu Luo (South China University of Technology, P.R. China); Ding-LIang Wen (South China University of Technology, P.R. China)
In this talk, the methods to design base-station antennas with stable radiation patterns in broadband are presented. Through a rational design of position of dipoles and a reflector, an antenna with a wide impedance bandwidth, stable radiation pattern and nearly identical E- and H-plane is achieved. According to the method, multi-dipole antennas with nearly 60% impedance bandwidth (SWR<1.5) and stable radiation patterns with 3-dB beamwidth 63.3±2.9 degree for E-plane and 63.4±2 degree at H-plane was achieved. On the other hand, it's well known that an electric dipole has a figure-8 radiation pattern in its E-plane and a figure-O pattern in the H-plane. Therefore, if a base station antenna is consisted of two dipoles orthogonal to each other, we can conclude that it has a stable 3-dB beamwidth with the horizontal and vertical plane because of the theory of radiation pattern complementation.
11:50 Low Profile Dual-Polarized Antenna Array for Operation at the K Band
Przemyslaw Gorski (Wroclaw University of Technology, Poland); Arkadiusz Byndas (Wroclaw University of Technology, Poland); Pawel Kabacik (Wroclaw University of Technology, Poland); Mariusz Hofman (Wroclaw University of Technology, Poland)
Gradual implementation of new services and new technologies at K-bands (i.e. 16-32 GHz), calls for major advancement in antenna array technology. Low-profile antenna are in particular desire. We present some results of investigations into antenna elements made for use in arrays. The main design objectives are antenna element capability to operate with a pair of orthogonal polarizations and low profile. The minimum bandwidth expressed in terms of not only impedance match, but with use of four other major antenna parameters is 1 GHz.
12:10 A Spectrally Efficient Chipless RFID Tag Based on Split-wheel Resonator
Md. Shakil Bhuiyan (Monash University, Australia); Nemai Karmakar (MONASH University, Australia)
A completely passive, compact and fully printable chipless RFID tag is proposed. The tag utilizes the scattering from an array of orthogonally polarized split-wheel resonator pairs to achieve multi-bit data capacity. As split-wheel resonators of identical resonance frequency but with orthogonal polarizations do not interfere with each other in their first mode of resonance, this allows realization of the same frequency band twice, once for each polarization, to encode information, thus enhancing the overall spectral efficiency of the proposed tag. When interrogated with broadband plane wave signals of two orthogonal polarizations, the reader detects the RCS peaks generated by each of the resonator pairs in both x- and y-polarizations and with n resonator pairs, effectively 22n-1 items can be tagged and identified. As the tags require only single sided metallization, direct printing of such tags using conductive ink on paper or polymer substrate can yield a ubiquitous electronic tagging method which can replace optical barcode in the future.

12:30 - 13:30

Lunch

13:30 - 15:00

Wearable Antennas/BAN

Chair: Thomas Kaufmann (The University of Adelaide, Australia)
A Printed Dual Band Antenna with a Ground Plane and Electromagnetically-Coupled Feed for Wireless Body Area Networks
Syed Muzahir Abbas (Macquarie University, Australia); Yogesh Ranga (CSIRO, ICT Centre, Australia); Karu Esselle (Macquarie University, Australia)
This paper presents a printed dual band antenna with a full ground plane and electromagnetically coupled feed for body area network devices operating in the industrial, scientific, and medical (ISM) band at 2.45 GHz and 4.9GHz public safety Wireless Local Area Networks (WLAN) band (4.94-4.99GHz). Performance along with parametric analyses are presented. Investigations have been carried out to assess its performance for body centric wireless communication. The electromagnetically-coupled feed is tuned to fill a null in the radiation pattern and to achieve impedance matching. The proposed antenna exhibits a wide radiation pattern along the body surface to provide maximum coverage and its narrow width (14mm) makes it suitable for on-body applications.
Shorting Strategies for a Wearable L-Slot Planar Inverted-F Antenna
Shengjian Jammy Chen (The University of Adelaide, Australia); Thomas Kaufmann (The University of Adelaide, Australia); Christophe Fumeaux (The University of Adelaide, Australia)
Wearable antennas are one of the key technologies supporting wearable wireless communication systems. A wearable textile L-slot planar inverted-F antenna is investigated in this paper with different shorting methods, namely a folded strip of silver fabric, embroidered vias and eyelets. The performance of the proposed antenna with these three shorting methods is compared through simulations with realistic shorting models. According to the obtained numerical results, the antenna has three resonances at 4.5 GHz, 5.0 GHz and 6.6 GHz. In terms of gain and efficiency, the embroidered vias shorting method, which is the simplest and cheapest method to implement, has slightly lower performance than the silver fabric folded strip and eyelet shorting methods due to its higher resistance.
Movement based time division multiplexing for near real time feedback body area network applications
Haider Sabti (Griffith University, Australia); David V Thiel (Griffith University, Australia)
A time division multiplexed coding system was designed and tested for a body-centric star network of six wireless sensor nodes mounted on an arm and leg and a central node (hub) on the chest during running. The proposed network allows a coordinated approach to gait analysis. The time sequence for communications between the wireless nodes and the hub is set during the first few steps as runners have different styles and can run at different speeds. After calibration the central unit sends a synchronization pulse during every running step and sets a unique transmission time window for each individual node. The time windows are scheduled when there is reliable communications between the hub and the sensor nodes around the body. Accelerometers on each node are used to identify these time windows for the diverse angles of rotation of the human limbs during running.
Dual mode Switch parasitic antenna for On/Off body communication channels
Mohammad Vatankhah Varnoosfaderani (Griffith University & Center for Wireless Monitoring and Application, Griffith University, Australia); David V Thiel (Griffith University, Australia); Junwei Lu (Griffith University, Australia); Manimaran Kanesan (Griffith Univesrity, Australia)
A dual mode hexagonal patch switch parasitic antenna is presented for off body and on-body communication at the same time. The position of the feed has been tuned to excite two modes ( and ) and make the antenna resonate at 2.45 and 5 GHz. Having different modes at two desired frequencies and using parasitic patch elements create directive and perpendicular radiation pattern at the same time for a dual band antenna. The 2.45 GHz frequency band can be used for over body communication because it can be directed in different parts of the body while the 5 GHz pattern is perpendicular to the antenna and is suitable for off-body communication.
Design of a All-fabric Higher Order Mode Circular Patch Antenna for Wireless Body Area Network Application
Jinpil Tak (Hanyang University, Korea); Jaehoon Choi (Hanyang University, Korea)
A all-fabric higher order mode circular patch antenna for Wireless body area network is proposed. The proposed higher order mode patch antenna has the maximum radiation direction along the body surface for on-body communication in the industrial, scientific, and medical 2.45 GHz band. In order to accomplish the low profile property, the proposed antenna used shorting posts to excite TM31 mode at 2.45 GHz ISM band. The proposed antenna was manufactured with fabric materials (conductive fabric, conductive thread, conductive epoxy and felt) and has a compact size. The proposed antenna has 28 mm (0.23 λ0) of a radius and 2 mm (0.016 λ0) of a thickness.
Wideband Body-Centric Channels Depending on Bandwidths in Various Environments
Miyuki Hirose (Tokyo Denki University, Japan); Takehiko Kobayashi (Tokyo Denki University, Japan)
The authors have focused on wideband, including Ultra-wideband (UWB, 3.1 to 10.6 GHz), on-boy radio propagation in various environments. Many studies have been reported about indoor propagation for narrowband and wideband. However previous study has not been examined characteristics between 10-MHz and 1-GHz frequencies. UWB technologies have been considered for use in wireless body area networks because of their possible low power consumption and anti-multipath capabilities. A series of propagation measurements campaign were carried out between on-body antennas in five different rooms. A new path loss and statistical models considering room volume had been proposed. In this paper, we evaluated propagation characteristics in various environments, especially examined the channels at 10-MHz to 1-GHz frequencies.
Inverted-F Antenna with Modified Current Distribution for SAR Reduction
Woo Cheol Choi (Yonsei University, Korea); Ki Joon Kim (Yonsei University, Korea); Young Joong Yoon (Yonsei University, Korea); Jeung Uk Ha (LG Electronics, Korea)
A design technique of Inverted-F Antenna (IFA) that can be easily applied to conventional antenna is presented for the Specific Absorption Rate (SAR) reduction. The proposed IFA has the characteristic of reducing only the effect of electromagnetic wave absorbed by the human body while maintaining good radiation performance compared to conventional IFA. The proposed IFA operates at 1.7 GHz, allocated in the GSM frequency band, and the solid phantom is used to evaluate the electromagnetic wave absorbed in the human body as an equivalent model of the human body. The size of proposed IFA is 90 mm x 50 mm including the size of the FR4 substrate whose thickness is 0.6 mm. The simulations are performed for analyzing the relationship between the distributed-current characteristic and SAR1g. The SAR1g value obtained by proposed IFA decreases about 11 % compared to the conventional IFA.

Millimeter-Wave Antennas and Components

Chair: Thomas Kaufmann (The University of Adelaide, Australia)
Field Tests of a 76GHz Automotive Radar with the Dielectric Lens and SAGE Algorithm
Yoshihiko Kuwahara (Shizuoka University, Japan); Shunsuke Sudo (Shizuoka University, Japan); Hiroyuki Kamo (Honda Elesys Co., Ltd, Japan)
Novel automotive radar of 76 GHz band has been manufactured and carried out the field tests. The radar features by multi-beam dielectric lens with super resolution by SAGE algorithm. For simple structure and small size, we used a patch array antenna as feed. Under strict constraints of the size, the lens shape has been designed by the multi-objective genetic algorithm. Through the field test, it is confirmed that 2 targets separated by 3.5m can be resolved over the range from 20m to 80m.
Millimeter Wave Antenna based on Substrate Integrated Waveguide for 94 GHz Communication Systems
Hamsakutty Vettikalladi (King Saud University, Saudi Arabia); Muhammad Saleem (King Saud University, Saudi Arabia); Majeed Alkanhal (King Saud University, Saudi Arabia)
The simulation results of a slot coupled membrane antenna fed by substrate integrated waveguide (SIW) is presented. The membrane antenna consists of 6 layers. The metallic patch placed on the top layer is excited by means of a longitudinal rectangular slot placed over the SIW to achieve impedance bandwidth of 5.4 GHz at center frequency of 94 GHz. The overall gain in the whole frequency band of operation of membrane antenna is found to be above 6 dBi.
Bifocal Wide Angle Lens With Optimized Construction Algorithm for 60GHz
Heiko Gulan (Karlsruhe Institute of Technology, Germany); Sören Marahrens (Karlsruhe Institute of Technology, Germany); Christian Rusch (Karlsruhe Institute of Technology, Germany); Benjamin Goettel (Karlsruhe Institute of Technology, Germany); Thomas Zwick (Karlsruhe Institute of Technology (KIT), Germany)
In this paper a dielectric bifocal lens for a 60GHz wide angle scanning antenna is presented. The lens is designed with the construction algorithm of Holt & Mayer [1], [2]. The construction algorithm is improved in a way that the bend of the lens towards the focal plane is no longer determined by empiric trial but calculated numerically with a bisection method. Finally a zoned bifocal lens made of high density polyethylene (HDPE) for a 60GHz scanning antenna is produced and measured. Comparison between measurement and simulation shows good agreement.
Miniaturized Integrated Butler Matrix for 180 GHz Chip-to-Chip Communication
Michael Jenning (Dresden University of Technology, Germany); Dirk Plettemeier (Dresden University of Technology, Germany)
This paper presents an improved Butler Matrix beam-switching network. The BM is designed for a thin film BCB technology on a silicon wafer. It can be placed on an interposer or 3D chip stack. The operational frequency will be at 180 GHz and the bandwidth exceeds 30 GHz. The size of the BM is below 1 mm2 . The field of application is ultra high speed short range inter-chip communication in the mm-Wave frequency range.
Design and Measurement of W-band Offset Stepped Parabolic Reflector Antennas for Airport Surface Foreign Object Debris Detection Radar Systems
Shunichi Futatsumori (Electronic Navigation Research Institute, Japan); Kazuyuki Morioka (Electronic Navigation Research Institute, Japan); Akiko Kohmura (Electronic Navigation Research Institute, Japan); Naruto Yonemoto (Electronic Navigation Research Institute, Japan)
Debris on the airport surface may cause a fatal damage for aircrafts. To detect these objects, foreign object detection (FOD) systems have been developing recently. By utilizing high-sensibility and weather robustness characteristics, the millimeter-wave radar is essential sensor devices for these systems. This paper discusses an offset parabolic reflector antenna for airport surface FOD detection radar systems. Firstly, the overview of the airport surface FOD detection radar systems, which employs between 96 GHz and 100 GHz band, is shown. For the azimuth beam scanning antenna, the antenna required to achieve both a narrow azimuth beamwidth and a wide elevation beamwidth. Secondly, the stepped parabolic reflector is newly designed to obtain an 8 degree elevation -20 dB down power beamwidth. Finally, the designed reflector is fabricated based on chemical wood materials. The measured result shows the 38 dBi gain and the 8.4 degree beamwidth for the elevation plane.
60GHz Pattern Reconfigurable Quasi-Yagi Antenna - Proof through Computational Design
Yi Yang (The University of New South Wales, Australia); Eric Chan (CSIRO, Australia); Rodica Ramer (University of New South Wales, Australia)
The paper demonstrates the possibility of designing pattern reconfigurable quasi-Yagi antenna. Adjusting the length of dipole arms and delay line, the E-plane radiation direction is steered from -20° to +20°, in 5° steps, without compromising the realized radiation gain or shifting the operating spectrum as high as 60GHz band. In this work, nine individual Yagi antennas with different beam directions are designed. They all have bands centered at 60GHz, with wide bandwidths covered from 55GHz to 65GHz.
Bandpass Filters Based on Coupled Split Ring Resonators for Surface Waves on Planar Goubau Lines
Ali K. Horestani (The University of Adelaide, Australia); Withawat Withayachumnankul (The University of Adelaide, Australia); Abdallah Chahadih (Lille University, France); Abbas Ghaddar (Lille University, Australia); Mokhtar Zehar (Lille University, France); Derek Abbott (University of Adelaide, Australia); Tahsin Akalin (Université de Lille 1, France); Christophe Fumeaux (The University of Adelaide, Australia)
This paper demonstrates a method for enhancing the performance of recently introduced compact bandpass filters for terahertz surface waves on single wire waveguides, the so-called planar Goubau lines (PGLs). It is firstly shown numerically and validated experimentally that a gapped PGL loaded with a pair of split ring resonators (SRRs) acts as a bandpass filter. The concept and simulation result are validated through experiment. Furthermore, in order to achieve an improved frequency response, a third-order filter based on coupled SRRs is proposed. It is shown that while the size of the proposed filter is further reduced, it additionally benefits from a higher in-band transmission, improved selectivity, and a controllable wide bandwidth.

Reconfigurable & Switchable Antennas

Chair: Thomas Kaufmann (The University of Adelaide, Australia)
Utilization of Tunable Components for 4G Frequency Reconfigurable Mobile Terminal Antenna
Aykut Cihangir (University of Nice Sophia Antipolis, France); Fabien Ferrero (CREMANT, Université Nice-Sophia Antipolis & CREMANT CNRS, France); Cyril Luxey (University Nice Sophia-Antipolis, France); Gilles Jacquemod (University of Nice, France); Alexandre Reinhardt (CEA-LETI, France); Laurent Dussopt (CEA, LETI, Minatec, France); Nicolas Lorphelin (DELFMEMS, France); Christophe Pavageau (DELFMEMS, France); Patrice Brachat (Orange Labs & France Telecom, France)
In this paper, two antenna designs using active components are presented for reflection coefficient tunability. The antennas are designed within the scope of the Artemos project and use MEMS switches and BST tunable capacitors internally available in the project. The first antenna uses an SPDT MEMS switch to select between one of the two target frequency bands (700-960MHz and 1.7-2.7GHz). The second antenna uses a tunable capacitor with a tuning range of 2.5-4pF, to frequency tune the reflection coefficient between 700 and 960MHz., The coverage of the 1.7-2.7GHz band is achieved by a monopole antenna who is fed separately.
A Polarization Reconfigurable Antenna for Dual-Band Operation
Peiyuan Qin (CSIRO Computational Informatics, Australia); Y Jay Guo (CSIRO, Australia); Can Ding (CSIRO Computational Informatics & Xidian University, Australia)
A polarization reconfigurable microstrip patch antenna is presented for wireless local area network (WLAN) dual-band operation (2.4 GHz and 5.8 GHz). The microstrip patch is aperture coupled to a microstrip line located along the diagonal line of the patch. The dual-band operation is realized by adjusting the frequency ratio of the TM10 and TM30 modes using four shorting posts. PIN diodes are employed to control the connection between the centre of each edge of the patch and the ground. By switching the PIN diodes, the proposed antenna can radiate either horizontal, vertical, or 45⁰ linear polarization in the two frequency bands. The antenna are fabricated and measured. Good agreement is observed between the measured and the simulated results on reflection coefficients.
The Design of Reconfigurable Antenna Arrays Using the Method of Vector Space Projections
Ruchi Chaturvedi (LNMIIT, Jaipur, India); Raghuvir Tomar (LNMIIT, Jaipur, India)
The reconfiguration problem of antenna arrays (when some array elements fail to operate) is studied using the wellborn method of vector space projections (VSP). The use of VSP allows one to impose a set of desired constraints thru "alternating projections" to furnish a design of self healing arrays i.e. retrieving the sane performance, over the degraded one. The method of VSP allows for the reconfiguration of antenna arrays subjected to any number of constraints, without changing the underlying complexity of the problem. By introducing a projection onto the set of dynamic range constraint (DRC), worthy results can be realized even in the case of 50% array element failure. To illustrate the VSP healing process, we performed simulations on linear and planar arrays depicting that it can be well exserted to 2-dimensional arrays. Finally, the outcomes are compared with the well known results and a significant improvement in the performance is concluded.
Compact Pattern Reconfigurable LTE Antenna
Jerzy Kowalewski (Karlsruhe Institute of Technology, Germany); Tobias Mahler (Karlsruhe Institute of Technology, Germany); Christoph Heine (Karlsruhe Institute of Technology, Germany); Thomas Zwick (Karlsruhe Institute of Technology (KIT), Germany)
This paper presents a compact pattern reconfigurable antenna for automotive mobile systems. The presented antenna operates in the 2.6 GHz LTE band in Europe and is capable of switching between four different directivity patterns. The generated main beams for these four states are shifted by 90 in azimuth in respect to one another. The antenna elements can be switched between active state or reflector state with the use of PIN diodes. With the chosen construction the PIN diodes can be easily fed with the help of a coaxial bias-T and a simple feeding structure. The measurement results prove good performance and the suitability for use in LTE applications.
Beam Scannable Microstrip Patch Antenna
Farooq Sultan (King fahd University of Petroleum and Minerals, Saudi Arabia); Sharif Iqbal Miru Sheikh (King Fahd University of Petroleum & Minerals (KFUPM), Saudi Arabia)
A novel beam scanning technique of a ferrite loaded microstrip patch antenna is presented. Beam scanning is produced from controlled interaction of the radiated fields and the gyromagentic properties of the axially magnetized ferrite rods. By varying the magnetizing fields of the ferrite rods, optimally placed in the near field region of the antenna, necessary phase taper of the radiated E-field distribution is achieved. The designed 10 GH antenna demonstrated an impedance bandwidth of 700 MHz and ±30° of beam scan for a changing magnetizing field of 170 kA/m. Employing embedded biasing coils through LTCC technology, the required biasing fields needed to achieve beam scan can be considerably reduced.
Correlation Coefficient Control For A Frequency Reconfigurable Dual-Band Compact MIMO Antenna Destined For LTE
Alexandru Tatomirescu (Aalborg University, Denmark); Emil Buskgaard (Aalborg University, Denmark); Gert Pedersen (Aalborg University, Denmark)
In this contribution, we are proposing a compact design for an implementation of a compact two element MIMO antenna destined for LTE smart phones. The antennas are collocated at one end of the PCB to minimize antenna volume. Each element is dual-band and frequency reconfigurable using tunable capacitors. The MIMO performance is investigated through efficiency, branch power imbalance and envelope correlation in two different channel models. The proposed antennas have acceptable levels of isolation between them, even in the low-bands, while having a good efficiency. Furthermore, the correlation coefficient is controlled by manipulating the ground currents between the antennas using a tunable capacitor. Nonetheless, using this mechanism to control the coupling between the antennas, the total efficiency is affected.
Characteristic Modes Analysis on Neutralizing Effect of Shorted Line for Two Adjacent PIFA Elements
Shen Wang (Yokohama National University, Japan); Hiroyuki Arai (Yokohama National University, Japan)
Two adjacent planar inverted-F antenna (PIFA) elements are used for a beam switchable antenna. But strong mutual coupling between the two closely arranged PIFA elements cannot be ignored. A shorted line connecting the two PIFAs is proved useful to provide neutralizing effect to reduce the mutual coupling. Optimized arrangement of PIFAs and the shorted line is shown, and the theory of characteristic modes is used to analyze that why the optimized shorted line make the mutual coupling reduce and how it works.
Planar Four-Port Quadri-Polarization Slot Antenna for Millimeter Wave Application
Yu-Jen Chi (National Chiao Tung University, Taiwan); Fu-Chiarng Chen (National Chiao Tung University, Taiwan)
This paper presents a planar, vialess printed slot dipole antenna with polarization switchable characteristic. The proposed design comprises four input ports, and each input ports corresponds to different polarizations such as horizontal polarization, vertical polarization, right-handed circular polarization, and left-handed circular polarization. Because lumped diodes are not available in millimeter wave frequency band, polarization diversity antenna design using diodes are not applicable. The proposed design does not require PIN diodes and DC biasing circuits, which makes it suitable to be used at higher frequency band. It can be easily printed on a circuit board and integrated with RF circuits using flip chip. The low cost and easy implement characteristic enables polarization agile antenna design for millimeter wave frequency band.

Arrays

Chair: Thomas Kaufmann (The University of Adelaide, Australia)
Analysis of Sparsely Sampled Phased Array Antenna for Advanced Doppler Radar
Farah Nadia Mohd Isa (International Islamic University Malaysia, Malaysia); Paul Brennan (University College London, United Kingdom)
This paper documents the study of a sparsely sampled phased array antenna used for an avalanche radar in VDLS. The fully populated array of 144 elements (16 x 9) is analysed and some of the prominent result are tabulated in this paper findings. The thinning method is based on the previous knowledge of the iterative method compiled by the author. It is shown that with the right thinning of the antenna elements, the beam pattern of the phased array antenna could be controlled to give the desired pattern to the designer.
A Compact Phase Shift Unit for Analogue Beamforming
Can Ding (CSIRO Computational Informatics & Xidian University, Australia); Y Jay Guo (CSIRO, Australia); Peiyuan Qin (CSIRO Computational Informatics, Australia); Luyang Ji (Xidian University & CSIRO Computational Informatics, Australia); Yintang Yang (Xidian University, P.R. China)
A novel phase shift unit for analogue beamforming is proposed. It is based on defected microstrip structure (DMS). The DMS unit has a phase shift of 15◦ with insertion losses below 0.5 dB at 5.2 GHz. It is etched on a 50 Ohm conventional microstrip line and the length of which is only 0.07 wavelengths long. Due to the low insertion loss and compact size, the DMS units can be easily cascaded to realize a higher phase shift. As an example, a 1-bit phase shifter made by cascading three DMS units is designed. It has a phase shift of 45◦1.8◦ with the insertion losses still below 0.5 dB across the 5.2 GHz band (5.15 GHz to 5.35 GHz). The phase shifter design based on DMS is compact, low cost, and easy to be fabricated and integrated in microstrip systems. Therefore, it provides a low cost solution for analogue beamforming which usually employs a large number of phase shifters.
Four-Branch Microstrip Leaky-Wave Antenna Array for Radiation Towards Broadside
Debabrata Kumar Karmokar (Macquarie University, Australia); Karu Esselle (Macquarie University, Australia); Stuart G Hay (CSIRO ICT Centre, Australia)
A half-width microstrip leaky-wave antenna (HW-MLWA) array for radiation towards broadside is presented. One of the main challenges of leaky-wave antennas is to radiate towards broadside. This can be achieved by a half-width MLWA array. Four uniform HW-MLWAs, terminated by 50Ω SMA coaxial loads, are used in the array. The full-wave numerical simulations show the ability of the proposed HW-MLWA array to radiate effectively towards broadside in a 200 MHz band around 4 GHz.
Design and Development of Low Noise Amplifiers for Connected Array Phased Array Feeds
Yogesh Ranga (CSIRO, ICT Centre, Australia); Robert Shaw (CSIRO, Australia); Stuart G Hay (CSIRO ICT Centre, Australia)
We describe analysis and design of two low-noise amplifiers (LNAs) suitable for connected array Phased Array Feeds (PAFs) operating in the 0.4-2 GHz frequency range. The LNAs combine single ended configurations to form balanced amplifiers with differential signal- and noise-match impedances in the order of 300 . Simulation results show noise temperatures of 25 to 45 K for the 0.45 to 0.9 GHz band and 30 to 45 K for the 0.9 to 2.0 GHz band.
Performance Comparison of Wideband Circularly-Polarized Antenna Arrays: Comparison of Microstrip-Line- and Metamaterial-Line-Based Feed Networks
Kwok Chung (University of Western Sydney, Australia); Sergey Kharkovsky (University of Western Sydney & UWS, Australia)
This paper presents performance comparison of two circularly-polarized antenna arrays where H-shaped antenna elements are used and arranged in fashion of planar sequential rotation in near-field region. The two identical arrays are fed by using the state-of-the-art metamaterial lines and conventional microstrip-lines, respectively. Through the comparison, it is shown that the array excited by metamaterial-line-based feed network can achieve wider axial-ratio (3-dB) bandwidth than the conventional counterpart, 89.3% versus 54.8%, while similar gain performances between arrays are observed.
Microstrip Patch Antenna Array at 3.8 GHz for WiMax and UAV Applications
Hassan Sajjad (King Saud University, Saudi Arabia); Waleed Tariq Sethi (King Saud University, Saudi Arabia); Khan Afridi (King Saud University, Saudi Arabia); Adnan Mairaj (King Saud University, Saudi Arabia)
This paper presents the design of a rectangular microstrip line-fed patch antenna array with a centre frequency of 3.8 GHz for WiMAX and Unmanned Air Vehicle (UAV) applications. A single element, 1x2 and 2x2 microstrip rectangular patch antennas were designed and simulated in Computer Simulation Tool (CST) Microwave Studio environment. The results of designed antennas were compared in terms of Return Loss (S11 parameters), bandwidth, directivity, gain and radiation pattern. The antenna was fabricated using Rogers Duroid RT-5880 substrate with a dielectric constant of 2.2 and a thickness of 1.574 mm respectively. The array antennas were measured in the laboratory using Vector Network Analyser (VNA) and the results show good agreement with the array antenna simulation

15:00 - 15:30

Coffee Break

15:30 - 17:30

New Materials and Composites for Antenna Applications

Chair: Kamran Ghorbani (RMIT University, Australia)
15:30 Efficiency Improvement of Small Slotted Annular Ring Antenna Using Laminated Conductors
Lotfollah Shafai (University of Manitoba, Canada); Robin Raju (University of Manitoba, Canada)
Ohmic Losses in a thin solid conducting element can be reduced significantly by the use of a composite conducting medium. The composite medium here consists of subsequent layers of thin laminated conductors, where the laminations are constituted by low loss dielectric of thickness comparable to the skin depth of the conductor. In this paper, firstly analytical study, showing the loss reduction in composite conducting media when compared to a single conductor case is presented. This concept is then applied to a miniaturized slotted microstrip annular ring antenna to improve its efficiency. It is seen that using the proposed technique around 20% improvement in efficiency was obtained.
15:50 Antennas on materials: small, robust, flexible
David V Thiel (Griffith University, Australia)
The expansion of wireless technologies for communications, inventory control, remote control and monitoring presents great challenges to antenna designers. While the radiation characteristics remain an important factor in all antenna design, the challenges of using antennas in difficult and dynamic environments, of low cost manufacture and environmental sustainability are additional parameters for the cost function using in computational optimization for the design of antennas. This paper reports the design constraints and optimized solutions of antennas for sports monitoring. A simple meander-line antenna fabricated in plastic has more than a 50% reduction in environmental impact compared to etched copper.
16:10 Conformal load bearing antenna structure using Carbon Fibre Reinforced Polymer (CFRP)
Kamran Ghorbani (RMIT University, Australia)
Over the last decade several methods of implementing load bearing antenna structure using CFRP have been reported, including Slotted Waveguide Antenna Stiffened Structure (SWASS) [2], and cavity backed slot antenna [3]. However by introducing the slot in the structure, the mechanical strength of the structure degrades. Hence the aim of this paper to report recent progress on reducing the size of the slot in the structure such as utilizing split ring resonator (SRR) beneath the slot antenna, small spiral antenna, and the split ring slot in the waveguide.
16:30 Recent Developments in Reflectarrays: Multi-Reconfiguration, Solar Cells, and Graphene
Julien Perruisseau-Carrier (Ecole Polytechnique Fédérale de Lausanne & EPFL, Switzerland)
This invited presentation will review our recent research activities related to reflectarray antennas. First, beamscanning reflectarrays with additional reconfiguration capabilities in polarization or frequency will be discussed, as well as arrays operating over multiple polarizations or frequencies. Second, initial results on the implementation of reflectarray antennas on thin-film solar cell panels will be presented. Finally, we will show how graphene can beneficially be used for implementing the reconfigurable reflectarray concept at terahertz or infrared frequencies.
16:50 Novel High-Tc Superconducting Devices for Wireless Communications and Imaging
Jia Du (CSIRO, Australia); Ting Zhang (CSIRO, Australia); Y Jay Guo (CSIRO, Australia)
High-Tc superconducting (HTS) materials have ultra-low surface resistance values at microwave frequencies, which have been applied to make high-Q resonators and "super filters" with narrow-bandwidth, low insertion losses, and superior out-of-band rejections. The second important property of HTS materials is related to low-noise Josephson junctions made from the HTS thin films. In recent years, novel nonlinear high-frequency devices, most of them exploiting the unique features of the AC Josephson effect, have been developed. Applications of the HTS devices based on Josephson junctions have been extended from lower electromagnetic bands (microwave) into mm-wave and terahertz, regions. An overview of CSIRO's recent research activities and achievements in developing novel HTS devices for applications to wireless communication and imaging is presented in this paper.
17:10 Field Computation in Inhomogeneous Media using Successive Projections
Stuart G Hay (CSIRO ICT Centre, Australia)
We formulate a successive projections approach to computing field scattering by inhomogeneous electromagnetic media. Solutions for the projections are derived in the space and space-harmonic domains. The key projections are shown to be expressible in terms of homogeneous-media Green's functions with complex wavenumbers, indicating possibilities for evaluation using existing representations and parallel techniques. The technique is implemented with the 3-dimensional Fast Fourier Transform algorithm and illustrative results in application to a lens antenna are presented.

18:00 - 19:30

Welcome Reception - Sponsored by Leap Australia

Chair: Y Jay Guo (CSIRO, Australia)

Wednesday, March 5

08:00 - 08:20

Registration Open

08:20 - 10:20

Arrays, MIMO, Beamforming and Indoor Propagation

Chair: Kevin W Sowerby (The University of Auckland, New Zealand)
08:20 Indoor Wireless Communications - An Electromagnetic Compatibility Challenge
Michael J Neve (The University of Auckland, New Zealand); Martin Leung (The University of Auckland, New Zealand); John Cater (The University of Auckland, New Zealand)
In this paper, a research programme tasked to develop propagation models for indoor wireless system deployment is outlined. The key feature of this work has been to use full-wave electromagnetic methods (in particular the Finite-Difference Time-Domain (FDTD) and Multi-Resolution Time-Domain (MRTD) methods) to isolate the mechanisms by which energy propagates in indoor environments. Simpler mechanistic models are then developed (which can frequently be based on ray methods in regions where they are shown to be valid) or alternatively on ray methods combined with with informed heuristic adjustments for regions in which a ray method applied in isolation is not valid.
08:40 Designing Buildings to Support High Capacity Wireless Networks
Kevin W Sowerby (The University of Auckland, New Zealand); Michael J Neve (The University of Auckland, New Zealand)
The capacity of wireless networks operating within buildings is dependent upon both the radio infrastructure and the indoor propagation environment. This paper studies the effect of internal wall attenuation on the ability to reuse a radio channel within a building. A metric for channel reuse potential is introduced and used to identify wall attenuations that maximize channel use within a typical office building environment. The results of this study inform the design of "wireless friendly buildings" that employ electromagnetic shielding and/or frequency selective walls.
09:00 Low-Cost Smart Antennas for Advanced Wireless Systems
Steven Gao (University of Kent, United Kingdom); Qi Luo (University of Kent, United Kingdom)
Smart antenna is a key technology for mobile communications, satellite communications, radar and sensors as it can enable the wireless systems to achieve the optimum performance by electronically steering its maximum radiation towards the desired directions while forming nulls against interfering sources. Traditional smart antennas are, however, complicated in structure, bulky, power hungry and costly. For commercial applications, it is important to reduce the size, mass, power consumption and cost of smart antennas. Firstly, this paper presents an introduction to smart antennas, followed by a brief review of various types of low-cost smart antennas. Then, several recent examples of low-cost smart antennas reported by the author's group are presented and discussed. These antennas are capable of achieving electronic beam steering within a wide angular range, while having compact sizes, low power consumption and low cost. A detailed list of references is given in the end of this paper.
09:20 Impact of Size and Decoupling Element on Some Fundamental Compact MIMO Antennas
Kun Zhao (Royal Institute of Technology & Sony Mobile Communication AB, Sweden); Shuai Zhang (Royal Institute of Technology, Sweden); Chi-Yuk Chiu (Sony Mobile Communications, P.R. China); Zhinong Ying (Sony Mobile, Sweden); Sailing He (Royal Institute of Technology, Sweden)
The effective bandwidth of fundamental MIMO antennas (ideal MIMO Dipole and ideal MIMO monopole) are studied in this paper. The S11 bandwidth, total efficiency bandwidth and envelope correlation coefficient bandwidth are shown, and effects from antenna sizes, matching and decoupling networks are analyzed. Furthermore, the effective bandwidth of MIMO antennas is defined in this paper as the overlap part of above three bandwidths; it can show a comprehensive performance of the MIMO system.
09:40 Research on Planar Antenna Arrays
Ronghong Jin (Shanghai Jiao Tong University, P.R. China); Sheng Ye (Shanghai Jiao Tong University, P.R. China); Xianling Liang (Shanghai Jiaotong University, P.R. China); Junping Geng (Shanghai Jiaotong University, P.R. China)
This paper presents the analytical and experimental works on coping with the popularity in wireless communications, especially in satellite communication. Firstly, the "image element" and "arc-shaped orthogonal feeding network" technologies are introduced for the single-band single-polarization antenna array design, the cross polarization is suppressed greatly and the antenna gain is improved. Moreover, an arbitrarily shaped planar array design technique is developed so that the antenna can be well conformal with the limited system space. Secondly, the high efficiency design of large scale antenna array in Ku band is introduced for single-band dual-polarizations antenna designs, including both active and passive array combination techniques. Thirdly, dual-band orthogonal-polarization technique is introduced and applied successfully in dual-band antenna array integrated designs, including linear and circular polarization, and then expanded to the multi-band multi-polarization array designs. Last, a digital beam forming array exhibits highly gain flatness in wide scan angle is presented, also, a novel simple yet accurate array calibration method is developed.
10:00 Optimal Design of Antenna Arrays
Geyi Wen (Nanjing University of Information Science and Technology, P.R. China)
A universal method for the optimal design of antenna arrays is introduced in this paper. The method is based on the optimization of the power transmission efficiency between the antenna array to be designed and a test antenna array whose elements are placed in the desired directions in which radiations need to be maximized. The optimized distribution of excitations for the antenna array is determined by an eigenvalue equation derived from the Rayleigh quotient for the power transmission efficiency. The method is applicable to any type of antenna array. To demonstrate its validity, different antenna arrays for various applications have been designed using the proposed method.

10:20 - 10:50

Coffee Break

10:50 - 12:30

Reconfigurable Antennas

Chair: Rodica Ramer (University of New South Wales, Australia)
10:50 Ultra-Wideband Conformal Apertures with Digital Beamforming for UHF to Millimeter-Wave Applications
John L. Volakis (Ohio State University, USA); Elias A. Alwan (The Ohio State University & The Electroscience Lab, USA); Dimitris Papantonis (Ohio State University, USA); Waleed Khalil (The Ohio State University, USA)
This paper presents a reconfigurable low profile ultra-wideband (UWB) phased array, having as much as 14.1:1 instantaneous bandwidth suitable for UHF to millimeter wave applications, with unprecedented integrated digital beam-forming capability across the entire bandwidth. To realize spectrum efficiency, aperture reconfiguration is also proposed. That is, the system is tuned at the feed network rather than the aperture of the antenna by introducing switches and LC loads. Further, the proposed UWB phased array significantly reduces cost due to its novel on-site encoding for tracking individual array element signals to eliminate hardware phased shifters, a primary cost component of the phased arrays.
11:10 Reconfigurable Deployable Antennas for Space Communications
Joseph Costantine (California State University Fullerton & American University of Beirut- Electrical and Computer Engineering Department, USA); Youssef Tawk (The University of New Mexico & Notre Dame University Louaize, USA); Christos Christodoulou (University of New Mexico, USA)
This paper discusses the merging of reconfigurable and deployable antennas for satellite and space communications. Reconfigurable antennas, normally proposed for terrestrial applications, allow deployable antennas to be more adaptive and more capable to perform additional functions. In this paper, various antenna concepts that can deploy and at the same time possess frequency tuning capability are proposed for space communications. The addition of tuning ability allows a more efficient, selective and cognitive communication schemes.
11:30 Low-Cost Beamforming Employing Reconfigurable Antennas
Y Jay Guo (CSIRO, Australia); Peiyuan Qin (CSIRO Computational Informatics, Australia); Can Ding (CSIRO Computational Informatics & Xidian University, Australia)
This paper presents CSIRO's recent research activities and achievements in low-cost beamforming employing reconfigurable antennas. Two novel concepts and configurations, a beam switching quasi-Yagi antenna and a phased array antenna based on a reconfigurable defected microstrip structure for phase shifting, are described. The beam switching of the pattern reconfigurable quasi-Yagi antenna is achieved by changing the phase difference of the currents on the two arms of the dipole. While, the operating mechanism of the DGS phase shifter is to alter the path of the current on the microstrip line. Future research directions are also discussed.
11:50 Multi-band, Dual Polarization, Dual Antennas for Beam Reconfigurable Antenna System for Small Cell Base Station
Seong-Ook Park (Korea Advanced Institute of Science and Technology, Korea)
Multiband, dual polarization dual antennas for beam reconfigurable antenna system suitable for small cell indoor wireless base stations is proposed. The whole design consists of horizontal and vertical antennas on a PCB board. Both the antennas are printed monopole type. The antenna supports LTE (1.7 - 2.1 GHz) and WLAN (2.5 GHz and 5.75 GHz) band frequencies. The simulated reflection coefficients |S11| of the proposed antenna shows that at operating frequencies undergo sufficient bandwidth lower than -7dB. Additionally, radiation characteristic of the presented antenna shows dual polarization behavior and switching states of the beam.
12:10 A Closely Spaced Switched Beam Antenna
Hiroyuki Arai (Yokohama National University, Japan)
This paper presents a switched beam antenna consisting of closely spaced two monopoles fed by its optimum amplitude and phase condition to obtain high gain in end-fire direction. The large mutual coupling is reduced by a decoupling circuit, and then a cardioid pattern is switched by selecting feeding port. The decoupling circuit is also replaced by a capacitor to keep the same network condition. This paper also discusses the super-directive condition of this array.

12:30 - 13:30

Lunch

13:30 - 15:00

Biomedical Applications

Chair: Thomas Fickenscher (Helmut Schmidt University, Germany)
Incorporating Estimated Green's Functions in Microwave Breast Cancer Imaging with DORT
Mohammed Jainul Abedin (CSIRO & CSIRO Computational Informatics, Australia); Stuart G Hay (CSIRO ICT Centre, Australia); Iain B. Collings (CSIRO, Australia)
The decomposition of reversed time (DORT) method is a promising algorithm for microwave breast cancer imaging. However when DORT is applied to breasts with high percentage of glandular tissues, its performance decreases due to differences in the dielectric properties of the physical and computational media. We propose a new method of deriving pair wise permittivities by using the received scattered signals in a multi antenna imaging system. We propose to use the estimated permittivities when computing the Green's function in the backpropagation step of DORT rather than using a nominal global value. We also propose to combine multiple eigenvectors of the time reversal operator. It is observed through simulation that our enhanced DORT method achieves improved focusing accuracy in detecting the breast malignancy.
Implantable Compact Antennas for Wireless Bio-Telemetry: A Comparative Study
Shahidul Islam (Macquarie University, Australia); Karu Esselle (Macquarie University, Australia); David Bull (BCS Innovations, Australia); Paul Pilowsky (Macquarie University, Australia)
This paper compares the performance of two compact implantable planar inverted-F antennas (I-PIFAs) designed to operate in the UHF ISM band around 900MHz. The total dimensions of Antenna 1 (Hilbert I-PIFA) and Antenna 2 (planar strip I-PIFA) are 25×33×7.6mm3 and 13.5× 11× 4.25mm3, respectively. A trade-off between the size, bandwidth and radiation efficiency is demonstrated. The larger antenna has a wider bandwidth as expected but both antennas operate well over the Australian ISM band. The radiation efficiencies of the two antennas, when implanted inside a rat, are 1.3% and 0.38%, respectively.
Unidirectional Antenna with Planar Reflector for Heart Failure Detection Systems
Sasan Ahdi Rezaeieh (The University of Queensland, Australia); Ummee Ahmed (The University of Queensland, Australia); Amin M Abbosh (The University of Queensland, Australia)
A broadband monopole antenna with unidirectional radiation is presented. The antenna is specifically designed for microwave systems aimed at the detection of heart failure. A reflector is added to the ground plane of the antenna to both enhance the bandwidth and directivity of the antenna. By the careful design of the radiator and reflector, the antenna achieves a broad operating bandwidth of 35.5% over the operating frequency of 684-980 MHz, which is used for the microwave-based imaging system for heart failure detection. The antenna has a compact size of 0.22 λ × 0.22 λ (where λ is the wavelength of the first resonance of the antenna). It provides a maximum gain of 4.7 dBi at 900 MHz, a stable and unidirectional radiation pattern.
Polarization Diversity on Microwave Tomography
Latifah Mohamed (Universiti Malaysia Perlis, Malaysia); Yoshihiko Kuwahara (Shizuoka University, Japan)
It is essential to reconstruct accurate images by microwave tomography to increase observation data based on the initialized distribution of electromagnetic properties over the imaging area. In this article, polarization diversity is applied to an imaging sensor consists of 4 linear arrays and 1 top circular array for the microwave tomography. From results, the simulated observation data can be accurately estimated. It is demonstrated by numerical simulation that the proposed method and sensor configuration can reconstruct images accurately.
Broadband Zigzag Corrugated Taper Slot Antenna for Heart Failure Detection Systems
Sasan Ahdi Rezaeieh (The University of Queensland, Australia); Amin M Abbosh (The University of Queensland, Australia)
A broadband unidirectional zigzag corrugated taper slot antenna for heart failure detection system is presented. A novel type of corrugation is used to keep the taper slot compact and provide a broad operating bandwidth. The antenna, which has the compact size of 0.22 λ × 0.26 λ, where λ is the wavelength of the first resonance of the antenna, covers the band 650-916 MHz, which is used in microwave-based heart failure detection. The antenna provides a stable gain of 1.6 dBi over its bandwidth with a stable unidirectional and symmetrical radiation pattern.
Low profile Ultra-wideband Directional Antenna Operating in Low Microwave Band for Brain Stroke Diagnostic System
Ahmed Mobashsher (Staff House Road, St Lucia & The University of Queensland, Australia); Amin M Abbosh (The University of Queensland, Australia)
Present imaging systems do not offer a low cost and portable solution for the stroke diagnosis. Microwave imaging systems have the potential to provide that solution and substitute, or complement, existing systems. To achieve that target, a wideband antenna operating at the band used for that application with directional radiation for adequate penetration into the human head is needed. This paper introduces a novel ultra-wideband antenna design consisting of a folded dipole-like structure printed on two dielectric slabs of the same size. The antenna covers a 98% fractional bandwidth (0.77 to 2.25 GHz), which is used in head imaging. The antenna exhibits stable directional radiation patterns with an average gain of 4.5 dBi and front to back ratio of 8 dBi. The overall structure of the antenna is equivalent to 0.27λ0 × 0.12 λ0 × 0.05 λ0, where λ0 is the corresponding wavelength at 0.77 GHz, which is a compact and low profile arrayable design suitable for microwave-based head imaging.
A Wideband Differential Directional Antenna for Head Implants
Terence S.P. See (Institute for Infocomm Research, Singapore); Wei Liu (Institute for Infocomm Research, Singapore); Xianming Qing (Institute for Infocomm Research, Singapore); Zhi Ning Chen (National University of Singapore & Institute for Infocomm Research, Singapore)
This paper presents the design of a wideband differential-fed antenna which is suitable for head implants. The antenna is fabricated using LTCC technology with an overall size of 24 × 10 × 0.95 mm. In order to ensure that the antenna is bio-compatible inside the head, a Teflon casing is constructed to house the antenna, wherein the head is modeled as a four-layered lossy and homogeneous structure. The antenna implanted in the head exhibits an impedance bandwidth of about 20% with a reference impedance of 100Ω at the center frequency of 4 GHz, the directivity of more than 5 dBi and the boresight gain of more than -8.3 dBi.

FSS, EBG, Reflect-Arrays & Meta-Surfaces

Chair: Thomas Fickenscher (Helmut Schmidt University, Germany)
Phase-compensated metasurface for conformal sectoral beam antennas
Dylan Germain (Université Paris Sud, France); Divitha Seetharamdoo (IFSTTAR, LEOST & Univ Lille Nord de France, France); Shah Nawaz Burokur (Institut d'Electronique Fondamentale - Université Paris-Sud, France); André de Lustrac (Institut d'Electronique Fondamentale - Université Paris-Sud, France)
The in-phase radiation from a conformal metasurface is numerically and experimentally reported. The LC-resonant metasurface is composed of a simultaneously capacitive and an inductive grid constituted by copper strips printed on both sides of a dielectric board. The metasurface is designed to fit a curved surface by modifying its local phase. The latter phase-compensated metasurface is used as a reflector in a conformal Fabry-Pérot resonant cavity antenna. Far-field measurements performed on a fabricated prototype allow showing the good performances of such a phase-compensated metasurface in restoring in-phase emissions from the conformal surface and producing a directive emission in the desired direction.
Phase-gradient metasurfaces for beam steerable antennas
Amirhossein Ghasemi (Université Paris Ouest La Défense, France); Shah Nawaz Burokur (Institut d'Electronique Fondamentale - Université Paris-Sud, France); Abdallah Dhouibi (Institut d'Electronique Fondamentale - Université Paris Sud, France); André de Lustrac (Institut d'Electronique Fondamentale - Université Paris-Sud, France)
Metasurfaces presenting a phase-gradient are designed at 10 GHz and are proposed to steer an antenna's radiated beam from broadside towards endfire direction. The metasurfaces are composed of both inductive and capacitive grids and the phase-gradient is achieved by modifying the elements in the inductive grid. Such phase-gradient metasurfaces are utilized as Partially Reflecting Surfaces (PRS) in Fabry-Pérot (FP) leaky-wave antennas (LWAs). Depending on the gradient used, beam steering up to 60° has been observed numerically and verified experimentally.
Design of Finite FSS-backed Reflectarray by Using BDP-CG Method
Keisuke Konno (Tohoku University, Japan); Qiang Chen (Tohoku University, Japan); Suguru Kameda (Tohoku University, Japan); Noriharu Suematsu (Tohoku University, Japan)
A reflectarray design method which has been proposed in reference is enhanced and applied to the design of reflectarray backed by frequency selective surface (FSS). For the design of FSS-backed reflectarray, phase variation of scattering field versus the size of reflectarray element including effect of mutual coupling with FSS elements must be calculated repeatedly. When the conventional direct solver is repeatedly used for calculating current of reflectarray element, CPU time for design of FSS-backed reflectarray becomes large. In this paper, instead of conventional direct solver, a block diagonal preconditioned-conjugate gradient (BDP-CG) method is used to enhance the design method.Results of numerical analysis show that the desired reflectarray can be designed by the enhanced method in small CPU time.
Carpet cloak with photonic crystal shield
Shenyun Wang (Nanjing University of Information Science & Technology, P.R. China)
In this paper, we report a carpet cloak using photonic crystal layers as an effective shield for substituting the PEC shield in the conventional carpet cloak. This carpet cloak permits communication with the outside when the frequency is out of the forbidden bandgap of the photonic crystal. The lateral shift at the reflection plane, which makes the carpet cloak detect-able, is considered and calculated with a Gaussian beam illumination. In order to counteract the lateral shift, we redesign the parameters of the cloaking slab by using the method of transformation optics. Good agreement has been obtained between the adjusted carpet cloak and ideal carpet cloak with a PEC shield.
Design of Dual-band Frequency Selective Surface with Miniaturized Elements
Amir Ebrahimi (University of Adelaide, Australia); Withawat Withayachumnankul (The University of Adelaide, Australia); Said Al-Sarawi (The University of Adelaide & Director of Centre for Biomedical Engineering, Australia); Derek Abbott (University of Adelaide, Australia)
A dual-band frequency selective surface (FSS) is introduced in this paper. By having a miniaturized unit cell size, the proposed FSS transmission response shows minimal sensitivity to the angle of the incident electromagnetic wave. The two passband frequencies of the proposed configuration can be controlled independently by tunning the unit cell geometrical parameters appropriately. An equivalent circuit model analysis is presented to provide an insightful synthesis procedure for the filter. Full-wave numerical electromagnetic simulations are used to confirm the analysis and synthesis method presented based on the circuit model.
Design of Polarization-Dependent Reflectarray for Terahertz Waves
Tiaoming Niu (University of Adelaide, Australia); Withawat Withayachumnankul (The University of Adelaide, Australia); Derek Abbott (University of Adelaide, Australia); Christophe Fumeaux (The University of Adelaide, Australia)
A reflectarray is designed for polarization-dependent beam deflection at 1 THz. Each unit cell is composed of two sets of dipole resonators, corresponding to orthogonal polarizations. The orthogonal dipoles are arranged in two interlaced triangular-lattice arrays. One subarray containing multiple unit cells provides a gradient phase response to complete a 2pi phase cycle over its length. This design demonstrates that it is possible to separate the polarization components of an incident beam by deflecting them into two different directions in a given plane. Numerical results predict successful implementation of the principle with available materials and within realistic manufacturing tolerances for operation at a frequency of 1 THz.
Screen printed frequency selective surfaces for room isolation in buildings
Aliya A. Dewani (Griffith University, Australia); Manimaran Kanesan (Griffith Univesrity, Australia); David V Thiel (Griffith University, Australia); Steven O'Keefe (Griffith University, Australia); Mohammad Vatankhah Varnoosfaderani (Griffith University & Center for Wireless Monitoring and Application, Griffith University, Australia)
A ring type frequency selective surface (FSS) can provide transmission stopband characteristics in rooms. This allows adjacent rooms to be isolated for one LAN for frequency reuse while other frequencies pass through the walls with minimal attenuation. The FSS was screen printed on a thin flexible plastic substrate of permittivity 3.2 with a stop band at 12.3GHz and 10dB bandwidth of 3.5GHz. The variation in bandstop characteristics was investigated for various wall materials. The centre frequency varied by more than 3 GHz for common wall materials which means significant transparency for some building materials. The technique is a low cost method of confining LAN picocells in one room.
3D Frequency Selective Surfaces with Wideband Response
Saidatul Azemi (RMIT University, Australia); Kamran Ghorbani (RMIT University, Australia); Wayne Rowe (RMIT University, Australia)
A novel 3D Frequency Selective Surface (FSS) with horn shaped resonators is proposed which exhibits a very wide stop band. This new horn shaped resonator is a modification from a 3D FSS consisting of square cylinder unit elements. This feature introduces frequency-selective surfaces with the added advantage of lowering the sensitivity of the FSS frequency response with respect to the incidence angle. Simulation results prove that the FSS can realize broad selectivity of waves with the bandwidth more than 57%. The wideband transmission behavior is stable under oblique TM incidence angles from 0 to 80 degrees. The influence of various key parameters on 3D Horn Shape FSS characteristics has been investigated using the CST simulation software tool. By understanding the effect of each parameter, a comprehensive study for a better design of 3D Horn Shape FSS with wideband response is presented.
Anisotropic cloaking of a metallic cylinder
Ladislau Matekovits (Politecnico di Torino, Italy); Yogesh Ranga (CSIRO, ICT Centre, Australia); Trevor S. Bird (Antengenuity & CSIRO, Australia); Karu Esselle (Macquarie University, Australia); Mario Orefice (Politecnico di Torino, Italy)
Electromagnetic footprint reduction for a metallic cylinder wrapped in a printed meta-surface is discussed. The meta-surface consists of a quasi-periodic pattern arrangement printed on a homogeneous dielectric layer of constant thickness, which is conformal to the cylinder, giving rise to an anisotropic cloak. Numerical analysis of the radar cross section (RCS) and field topography around the cloaked cylinder for different polarizations of the incident plane wave are considered, and it is demonstrated that the proposed solution reduces the RCS of the cylinder differently for variable incidence.
Electromagnetic Band Gap Materials Enhance Radar Cross section of Trihedral Corner Reflectors with Circular Polarization Under Rain Conditions
Demyana Saleeb (Kafr Elshiek University, Egypt); Ahmed Saad Elkorany (menouf, menoufia, Egypt); Said Elhalafawy (Menouf, Menoufia, Egypt); Arafa Nasef (Faculty of Engineering, Kafr Elshiekh University, Egypt)
Radar with circular polarization suppresses rain clutter. Trihedral corner reflectors are used to make civil marine radars visible. But trihedral corner reflectors with circular polarization are inefficient in rain conditions. The solution to this problem is to make the corner reflector convert polarization of the incident wave from circular to linear. Solutions available in the literature are: difficult to implement, make corner reflectors fragile, expensive and narrow band. In this paper an electromagnetic band gap material is designed to cover one panel of the corner reflector to convert polarization of incident wave from circular to linear. These materials are low profile, low cost and simple to construct.
A Low-Profile Single-Layer UWB Polarization Stable FSS for Electromagnetic Shielding Applications
Irfan Sohail (Macquarie University, Australia); Yogesh Ranga (CSIRO, ICT Centre, Australia); Ladislau Matekovits (Politecnico di Torino, Italy); Karu Esselle (Macquarie University, Australia); Stuart G Hay (CSIRO ICT Centre, Australia)
A low-profile frequency selective surface (FSS) exhibiting effective shielding over a large bandwidth is presented. The FSS unit-cell consists of a cross-dipole and a ring printed over the opposite surfaces of a low-cost FR-4 substrate. The design demonstrates a wide 7.5 GHz stopband and provides necessary shielding in both X- and Ka- bands simultaneously. The numerical investigations confirm the shielding behaviour of this FSS with more than 20 dB attenuation and 74% bandwidth in 6.5-14 GHz. Moreover, it shows angular stability for both TE and TM polarization at various angles of incidence up to 45 degree.

Multi-Band Antennas

Chair: Thomas Fickenscher (Helmut Schmidt University, Germany)
Circularly Polarized High Gain Multiband Antenna for Non-Linear Junction Detector System
Kim In-hwan (Korea Maritime and Ocean University, Korea); Kyeong-sik Min (Korea Maritime and Ocean University, Korea)
This paper proposes a design of multiband circular polarization patch array antennas for non-linear junction detector system application. A patch antenna with the inclined three slots, two rectangular grooves on circular disc patch, the asymmetric gap of the CPW feeding structure and the truncated corner of ground plane was considered for circular polarization and broad bandwidth. In order to improve gain and to keep small size in array antennas, the optimized rectangular slot array located on common ground plane was designed. The calculated and the measured return loss and axial ratio of array antennas were showed good agreement. The higher gain of about 1 dBi was realized by using the common ground structure with the novel slot array to suppress mutual coupling.
Dual-Band VHF/UHF Smartphone Antenna for Mobile Digital Television
Andrew R Weily (CSIRO Computational Informatics, Australia); Ken Smart (CSIRO Computational Informatics, Australia); Trevor S. Bird (Antengenuity & CSIRO, Australia)
A dual-band VHF/UHF antenna suitable for use with a portable media device is proposed. The antenna is designed to attach to a smartphone or tablet as a folding cover. It uses a capacitively-coupled element for the VHF antenna and a shorted dipole for the UHF antenna. A low-pass filter network couples the two antennas together so they can be fed from a single port. Applications of the antenna are for the reception of mobile digital television signals such as the ATSC M/H standards or DVB-H on portable media devices such as smartphones or tablets.
Dual Band Microstrip Patch Antenna for WiMAX and WLAN Applications
Muhammad Haroon Tariq (National University of Sciences and Technology (NUST), Islamabad, Pakistan)
A dual band microstrip patch antenna has been designed for technology oriented requirements of high speed wireless local area networks (IEEE 802.11a standard) and other communications systems covering the 5.15-5.825 GHz band. Three parallel slots have been introduced in the radiating patch to get the maximum current distribution on the surface. The position of center arm is set to get the radiation pattern in desired outward direction. The effects of various dimensional parameters were analyzed to get the optimized performance of the presented antenna. FR-4 substrate has been used for cost estimation whereas size reduction and enhanced gain of the structure was another challenge. To meet this challenge impedance is matched while maintaining the width of the transmission line and also addition of slots is responsible for enhanced performance of antenna. The simulated results are good in agreement with measured results making antenna to be used for WiMAX and WLAN applications.
Dual-band MIMO antenna using double-T structure for WLAN applications
Wen Zhao (The University of Hong Kong, Hong Kong); Li Liu (The University of Hong Kong, Hong Kong); William S. W. Cheung (The University of Hong Kong, Hong Kong); Yunfei Cao (The University of Hong Kong, Hong Kong)
A dual-band multiple-input-multiple-output (MIMO) antenna is proposed for the wireless-local-area-network (WLAN) applications in the 2.4-GHz and 5.2-GHz bands. The antenna consists of two double-T monopole elements with microstrip-fed and symmetrically placed on a substrate. To enhance isolation between the two monopole elements, three slots are cut on the ground plane on the other side of the substrate. The longer slot is used for better isolation in the 2.4-GHz band, while the two shorter slots are used for the 5.2-GHz band. Simulation and measurement are used to study the antenna performance in terms of S parameters, radiation patterns, realized gain, efficiency, and envelope correlation coefficient. Results show that the MIMO antenna has the two operation bands of 2.20-2.75 GHz and 5.09-5.50 GHz with mutual coupling of less than -15 dB and envelope correlation coefficient of less than 0.1, making it a good candidate for WLAN applications.

Wireless Systems

Chair: Thomas Fickenscher (Helmut Schmidt University, Germany)
Ultrasonic Radar Sensor Installed in Sensor Network - Technique Advanced from Millimeter-Wave Radar -
Mitsutaka Hikita (Kogakuin University, Japan); Tateo Sato (Kogakuin University, Japan)
A new concept called "Sensor Network" has been proposed by combining sensor technologies together with radio communications system such as cellular-phone. Sensed signals from many sensor nodes distributed in home, office and public places are collected to a center node by small local radio network. Millimeter-wave radar systems using 76GHz have been introduced in high-end vehicles. Based on similar technique used in millimeter-wave radar, we have proposed a novel ultrasonic measurement method. It provides information of moving objects, and can be installed in sensor network. In the future, these systems will be very useful in care environment to monitor the elderly or sick persons. In this paper, both theoretical investigation and fundamental experimental results will be presented.
RFID Reader Pad using Free Access Transmission Line for Arbitrary Oriented Tag Antennas
Takuya Okura (Yokohama National University, Japan); Hiroyuki Arai (Yokohama National University, Japan)
In this paper, we propose a new RFID reader pad using free access transmission line. Previously, the authors proposed the diamond shaped structure using free access transmission line as RFID reader pad and circularly polarized antenna to obtain a stable coupling in any antenna direction. However, this pad does not provide stable coupling with other kinds of antenna. To overcome disadvantage, we propose a square shaped crossed transmission line. This paper presents a prototype reader pad and its characteristics and present stable coupling characteristics.
EVM and BER Evaluation of C band New Airport Surface Communication Systems
Kazuyuki Morioka (Electronic Navigation Research Institute, Japan); Naoki Kanada (Electronic Navigation Research Institute, Japan); Shunichi Futatsumori (Electronic Navigation Research Institute, Japan); Junichi Honda (Electronic Navigation Research Institute, Japan); Akiko Kohmura (Electronic Navigation Research Institute, Japan); Naruto Yonemoto (Electronic Navigation Research Institute, Japan); Yasuto Sumiya (Electronic Navigation Research Institute, Japan); David Asano (Shinshu University, Japan)
AeroMACS (Aeronautical Mobile Airport Communication System) is proposed for future airport surface communication system at C band. In this paper, we report the results of an experiment at Sendai airport in Japan to evaluate the AeroMACS. Our base station covers about 3km times 1km rectangular airport surface by 1W transmit power. It is required that BER (Bit Error Rate) is under 10^-6 at physical layer in order to realize reliable data communication systems. However, measurement of BER is difficult especially in field experiment because another data link is required to notify transmit symbols to the receiver. So, we calculate the relationship between EVM (Error Vector Magnitude) and BER by computer simulation. Then, we translate EVM which is measured in the experiment into BER. The results show that 64QAM-3/4 can be used in the 64.3% of LOS (Line Of Sights) area and 64QAM can't be used in almost all NLOS (Non Line Of Sights) area at Sendai airport.
Evaluation by Scale Model Experiments for Aeronautical MIMO Systems
Naoki Kanada (Electronic Navigation Research Institute, Japan); Kazuyuki Morioka (Electronic Navigation Research Institute, Japan); Yasuto Sumiya (Electronic Navigation Research Institute, Japan); Naruto Yonemoto (Electronic Navigation Research Institute, Japan); Makoto Shioji (Electronic Navigation Research Institute, Japan); Akiko Kohmura (Electronic Navigation Research Institute, Japan); Shunichi Futatsumori (Electronic Navigation Research Institute, Japan)
A new high-speed aeronautical MIMO system is currently being considered for airport communications. We evaluate effectiveness of scale model experiment by comparing MIMO channel capacities around an aircraft between actual and scale model systems. The channel capacities of the scale model indicate a similar tendency to the actual aircraft in the whole band of the communication systems. Therefore, we verified that scale model experiment is effective for evaluation of aircraft that have a complex shape.
An assessment of simulation methodologies for the analysis of near-field radiation zones related to human exposure
Hugo G. Espinosa (Griffith University, Australia); David V Thiel (Griffith University, Australia); Chris Brindley (Corearth Australia Pty Ltd, Australia)
The reliable evaluation of electric and magnetic field exposures with relevant radiofrequency exposure limit standards is important in order to provide protection against known adverse health effects. The evaluation of human exposure levels to radiofrequency, electric and magnetic fields and power density is required for assessment of compliance with technical standards, and it can be conducted by either measurement or numerical calculation. This paper presents a comparison between different computational tools for the analysis of zone boundaries for human exposure to radiation from a Yagi-Uda antenna, operating at 450MHz with a maximum power of 50W. The results are based on the guidelines for limiting exposure to time-varying electric, magnetic and electromagnetic fields, created by the International Commission on Non-Ionizing Radiation Protection (ICNIRP).
Antenna Placement on a Large Mining Vehicle
Thomas Kaufmann (The University of Adelaide, Australia); Urban Maeder (SAFEmine AG, Switzerland); Christophe Fumeaux (The University of Adelaide, Australia)
For collision avoidance systems in mining equipments, antennas need to be placed close to large metallic vehicles. This paper estimates the impact of a vehicle on the radiation pattern of a monopole antenna in the lower GSM band for various distances, antenna heights and frequencies around 900 MHz. The received power at a smaller truck for various positions up to a radius of 500 m is estimated using computed radiation patterns coupled to the Friis transmission equation including plane earth loss. It is shown that due to shadowing on the large mining vehicle, the signal strength can be reduced by up to 20 dB, which however can be mitigated by increasing the height of the antenna on the vehicle.
Effect of Antenna Bandwidth and Placement on the Robustness to User Interaction
Emil Buskgaard (Aalborg University, Denmark); Alexandru Tatomirescu (Aalborg University, Denmark); Samantha Caporal Del Barrio (Aalborg University, Denmark); Ondřej Franek (Aalborg University & APNet Section, Denmark); Gert Pedersen (Aalborg University, Denmark)
Modern smart phones require antenna systems that can deal with an ever-growing number of bands. This study compares a wide-band antenna covering a whole band at once and a tunable narrow-band antenna covering only one channel at a time. The WB and the NB antenna are placed both at the top and the bottom of the phone. All antenna configurations are simulated in talk position with a head and a hand. The hand is constructed with a movable index finger that is swept at 6 positions on the backside of the phone. The study shows that wide-band antennas de-tune a lot more than narrow-band antennas and top-mounted antennas are experiencing more than 6 dB higher losses compared to the bottom-mounted antennas. It is proposed to expand this study with more antenna types and placements and to compare the simulation results to measurements to increase the confidence in the results.

15:00 - 15:30

Coffee Break

15:30 - 17:30

Metamaterials and EBGs

Chair: Ladislau Matekovits (Politecnico di Torino, Italy)
15:30 Dual-band Metaloop Antenna
Hisamatsu Nakano (Hosei University, Japan); Kenta Yoshida (Hosei University, Japan); Junji Yamauchi (College of Engineering, Japan)
This paper presents a metaloop antenna, which radiates a dual-band counter circularly-polarized (CP) wave. The antenna characteristics, including the radiation pattern, gain, and VSWR, are discussed. The radiation efficiency is also discussed. It is found that the gain increases by 3.5 dB for the left-handed CP wave and 4.8 dB for the right-handed CP wave, when the antenna height is changed from 1.6 mm to 3.2 mm. The VSWR is small within the gain bandwidth, as desired.
15:50 Radiation by a Dipole Antenna on the Axis of a Semi-Spheroidal Cavity Partially Filled with DNG metamaterial
Piergiorgio L.E. Uslenghi (University of Illinois at Chicago, USA); Danilo Erricolo (University of Illinois at Chicago, USA); Tadahiro Negishi (University of Illinois at Chicago, USA)
An oblate semi-spheroidal cavity under a metal plane, partially filled with DPS material and DNG metamaterial is considered. The DPS and DNG regions are separated by a coordinate surface in the oblate spheroidal system. The primary source is a dipole located on the axis of symmetry of the structure and axially oriented. The field inside the cavity and the radiated field above the metal plane are found exactly. Numerical results are shown and discussed.
16:10 Three Kinds of Microwave Metamaterial Lenses
Tie Jun Cui (Southeast University, P.R. China); Wenxuan Tang (Southeast University, P.R. China)
In this talk, we present three new types of microwave metamaterial lenses: a three dimensional (3D) flat lens for broadband, high-gain and low-sidelobe radiations, and two imaging lenses for super-resolution images in near and far fields, respectively.
16:30 Metamaterial Arrays and Applications: FSS, EBG & AMC structures
J (Yiannis) Vardaxoglou (Loughborough University, United Kingdom)
Over the past decade, interest in applications metamaterials has grown explosively. The potential take-up of these structures in communication and sensing systems is primarily due to the control of the amplitudes, frequencies and wave-numbers of propagating and non-propagating electromagnetic modes to an extent that was not previously possible. Matamaterials have the potential to control the electromagnetic modes in various application fields such as indoor and outdoor communication systems, communicating mobile objects, transport systems(cruise liners and high-speed trains), space/earth communication and microelectronics, at µ-wave, mm-wave frequencies. An overview of the work in FSSs, EBGs and AMCs of the Wireless Communications Research Group at Loughborough University, UK will be presented.
16:50 Effective Techniques for Extending the Directivity-Bandwidth of Resonant Cavity Antennas
Raheel Hashmi (Macquarie University, Australia); Basit Ali Zeb (Macquarie University, Australia); Karu Esselle (Macquarie University, Australia)
We present extremely simple techniques developed recently to address the bandwidth enhancement of resonant cavity antennas (RCAs) made out of unprinted dielectric slabs. These techniques are suitable for both unit-cell superstrate models as well as the finite-size RCA model in which superstructure area is optimized to increase the 3dB directivity bandwidth of RCA. It is shown that controlled dielectric and thickness contrast can be used as a defect to create wideband RCA superstrates in unitcell design whereas the use of small superstrate area can directly enhance the 3dB bandwidth. Prototype antenna design is presented and results are included to demonstrate the improvements obtained. Significant improvements in 3dB bandwidth (50%) have been observed as compared to conventional designs while conserving design simplicity, practicality and ease of fabrication, which are the key advantages of presented techniques.
17:10 Tunable, switchable, and one-way electromagnetic wave absorbers based on metamaterial structures
Yijun Feng (Nanjing University, P.R. China); Bo Zhu (Nanjing University, P.R. China); Junming Zhao (Nanjing University, P.R. China); Hao Yuan (Nanjing University, P.R. China); Liang Sun (Nanjing University, P.R. China); Tian Jiang (Nanjing University, P.R. China)
In this presentation, we will report on several controllable metamaterial absorbers that are realized by integrating resonant unit cell structure with microwave varactors or diodes, as well as a one-way microwave energy absorber based on a composite metamaterial structure including chiral structure. These metamaterial absorbers with tunable, switchable or one-way performances could find application in many functional devices for manipulation of the EM wave propagation and the design concept could also be scaled to other frequency band such as terahertz or optical range.

19:00 - 22:00

Conference Banquet - (Harbour Ballroom, King Street, Wharf 2)

Chair: Y Jay Guo (CSIRO, Australia)

Thursday, March 6

08:00 - 08:20

Registration Open

08:20 - 10:20

Millimeter-wave, THz and Optical Antennas

Chair: Goutam Chattopadhyay (JPL, USA)
08:20 Dielectric Resonator Nano-Antennas: A Pathway to Efficient Optical Antennas
Christophe Fumeaux (The University of Adelaide, Australia); Longfang Zou (The University of Bristol, United Kingdom); Withawat Withayachumnankul (The University of Adelaide, Australia)
The talk will describe the various challenges associated with the design and realization of dielectric resonator antennas, and give a perspective on the potential of DRAs operating in their lower resonant modes, as building block for optical components, from the low terahertz spectrum to the visible range.
08:40 Silicon Micromachined Terahertz Receiver Systems
Goutam Chattopadhyay (NASA-JPL, Caltech, USA)
Majority of today's terahertz systems use waveguide based circuits, coupling structures, and antennas primarily to reduce loss. As the operating frequencies of these systems go beyond a couple of hundreds of gigahertz, due to small feature sizes and micron-scale tolerance requirements, it becomes difficult to realize these components with traditional metal machining. It gets even more challenging when multi-pixel terahertz instruments are designed, built, and integrated in focal-plane array architecture. One viable solution to overcome this is to use silicon micromachining. In silicon micromachining, waveguide components and associated circuitry are fabricated using photo-lithography techniques on silicon substrates. The fabricated structures are coated with sputtered gold and assembled in split-block architecture. With these fabrication and assembly techniques, a high level of integration is possible where multiple circuits can be integrated on a single-layer of silicon wafer. Multiple wafers can be stacked vertically to complete a receiver system. In this talk details of such terahertz systems will be presented.
09:00 Millimeter Wave Wireless Networks with Diversity against Localized Rain
Makoto Ando (Tokyo Institute of Technology, Japan); Jiro Hirokawa (Tokyo Institute of Technology, Japan); Takuichi Hirano (Tokyo Institute of Technology, Japan); Hung V. Le (Tokyo Institute of Technology, Japan); Toru Taniguchi (Japan Radio Co., Ltd., Japan); Riichiro Nagareda (KDDI R&D Laboratories Inc., Japan); Akira Yamaguchi (KDDI R&D Laboratories Inc., Japan)
Previous studies on the intensive propagation, have been conducted for macroscopic behaviors of rain and link availability together with diversity effects are evaluated for relatively long distance radio links such as terrestrial and satellite communications, where relatively weak rain events are the main interest. In this paper, evaluation of behavior of rain and its effect on link attenuation in Tokyo Tech millimeter-wave model mesh network are presented. The unique effects due to highly localized behaviors of the strong rain have become clear and are characterized in terms of variogram instead of correlation coefficients. Spatial separation even in the small network consisting of the links less than 1 km provides effective diversity branches for better availability performance.
09:20 Design of Inhomogeneous Dielectric Flat Lens with 2×2 TacLamPLUS Microstrip Array Feeder
Mustafa K. Taher Al-Nuaimi (State Key Laboratory of Millimeter Waves, Southeast University, P.R. China); Hong Wei (Southeast University, P.R. China); Wen-Xun Zhang (Southeast University, P.R. China)
The design of single slab inhomogeneous zoned dielectric lens is presented in this paper. The design of the lens is based on the phase correction philosophy. The proposed lens consists of 16 annual zones of same width of 2.32mm but different phase correction and each zone itself is considered as phase shifter which is independent from other zones in the lens as will be explained later in this paper. The required phase correction at each zone is obtained by drilling numerous holes having different diameters through the dielectric host material. The proposed lens is only 6.35mm thick and has diameter of 72mm. A small 2×2 planar microstrip array feeder based on very low loss TaclamPLUS material rather than conventional 3D horn antenna is used for easier integration with other planar circuits. A peak gain of 28dBi at 74GHz is achieved which is 14.7dBi higher than the gain of the feeder alone.
09:40 A New Class of Printed Leaky Wave Antennas
Yahia Antar (Royal Military College of Canada, Canada)
The basic properties of leaky wave antennas were founded in the pioneering work of Tamir and Oliner back in the early 1960s and later in the work of Jackson and Oliner. Recently, the need for high gain printed antennas has revived interest in leaky waves resulting in a great number of papers on printed leaky wave antennas. In here we discuss leaky waves analytical properties and their supporting structures. A new coplanar surface wave- based launcher feed system for direct excitation of leaky waves is described. Various high gain planar antenna configurations with partially reflecting screens will be studied in detail as examples of new scanning leaky wave antenna structures. Analysis of some of these structures reveals the main properties of leaky wave antennas and provides some physical insight into their nature and future potential developments. In addition, and based on the unique properties of the newly developed surface wave launchers, a new way of designing associated microwave guiding structures for integration with antennas or for use on their own in microwave circuits is presented.
10:00 Measurement Setups for Millimeter-Wave Antennas at 60/140/270 GHz Bands
Xianming Qing (Institute for Infocomm Research, Singapore); Zhi Ning Chen (National University of Singapore & Institute for Infocomm Research, Singapore)
Antenna development at millimeter-wave (mmW) bands has many unique challenging issues wherein the measurement is one of the toughest one because of the expensive testing setup, limited system dynamic range, complicated and tedious calibration as well as measurement procedures. Furthermore, cable, connector or probe used in the measurement shows non-ignorable effect on the measurement results of the antenna under test (AUT), which must be considered carefully in the measurement system configuration. In this paper, we present three measurement setups for mmW antennas at 60 GHz, 140 GHz and 270 GHz bands, respectively. The detailed setup configurations are addressed to achieve the maximum system dynamic range with the available commercial accessories. The setups are successfully used to characterize a number of antennas at 60/140/270 GHz bands with different feeding connections (coax, waveguide and probe). The measured radiation patterns show very good agreement with the simulations.

10:20 - 10:50

Coffee Break

10:50 - 12:50

Wearable Antennas and Biomedical Applications

Chair: Andrew R Weily (CSIRO Computational Informatics, Australia)
10:50 New Challenges in the Design of Electromagnetic Communication Systems
Raj Mittra (Penn State University, USA)
New Challenges in the Design of Electromagnetic Communication Systems
11:10 Dual-mode Wearable Antenna for On-/off-body Wireless Communications
Chia-Hsien Lin (Chiba University, Japan); Koichi Ito (Chiba University, Japan)
Body-Centric Wireless Communications (BCWCs) using wearable wireless devices are received an increasing amount of attention due to wide applications such as medical care system, identification system, smart home and entertainment. In this paper, we proposed a wearable dual-mode (on- / off- body modes) antenna for medical care system. In this paper, electric field distribution is analyzed for the on-body mode and reflection coefficient (S11) and radiation patterns are discussed for the off-body mode.
11:30 Low-Profile Antennas for On-Body Surface Communications
Jaehoon Choi (Hanyang University, Korea); Jinpil Tak (Hanyang University, Korea); Kyeol Kwon (Hanyang University, Korea)
In this paper, low-profile antennas for on-body surface communication are introduced. A circular-ring patch antenna with TM31 higher order mode for monopole-like radiation characteristic with low-profile in ISM 2.45 GHz band is proposed. A center-fed circular patch antenna with corrugated ground for surface wave guide in ISM 5.8 GHz band is also proposed. The 10-dB return loss bandwidths are wide enough to cover the whole ISM 2.45 GHz (2.4 GHz - 2.485 GHz) and ISM 5.8 GHz (5.725 GHz - 5.825 GHz), respectively. The circular-ring patch antenna with TM31 higher order mode has monopole-like radiation characteristic with low-profile. And the center-fed circular patch antenna with corrugated ground for surface wave guide has the maximum radiation at θ = 90°. Therefore they are well suited for WBAN on-body communication.
11:50 Microwave-Based System Using Directional Wideband Antennas for Head Imaging
Amin M Abbosh (The University of Queensland, Australia)
Recent advances indicate that microwave-based imaging systems have the potential to be used for different medical applications, such as head imaging. This application is specifically important for fast brain stroke detection. It is shown in this paper that a system designed to operate across the band from 1-4 GHz enables achieving satisfactory imaging results of the brain. The system uses an array of directional antennas that have corrugated tapered slot structures. Details of the system with some initial results in addition to the technical challenges facing that system are explained.
12:10 Towards Analytic Path Loss Models in On-Body Wireless Communications
Dirk Manteuffel (University of Kiel, Germany)
In this research, we evaluate the feasibility of analytic on-body path loss models in wireless body area networks based on Norton surface waves. The evaluation is based on a refined formulation of Norton surface waves [1] excited by an antenna near dissipative media by Bannister [2] and its applicability to the constitutive parameters of different body tissues at typical operation frequencies of on-body wireless applications (0.4 < f[GHz] <60). The numerical verification is based on homogeneous flat body scenarios. This is followed by examples of propagation paths on an inhomogeneous anatomically correct human body model. As the Norton theory is based on a flat propagation scenario the effect of the curvature of the body has to be introduced by corrective terms for the ground wave and the Norton surface wave, respectively. The results obtained are promising with respect to the development of analytic path loss modes for on-body wireless propagations.
12:30 Indoor Positioning using Novel Multi-loop HF RFID Reader Antennas
Ananda Sanagavarapu Mohan (University of Technology Sydney (UTS), Australia); Mohd Yazed Ahmad (University of Malaya & Faculty of Engineering, University of Malaya, Malaysia)
This paper presents multi-loop bridge reader antennas for HF RFID based indoor positioning. Experimental results obtained for positioning an autonomous wheelchair will be presented.

12:50 - 13:45

Lunch

13:45 - 15:30

Wideband and UWB Antennas

Chair: Peiyuan Qin (CSIRO Computational Informatics, Australia)
Compact UWB Power Divider with Unequal Distribution Ratio
Feng Wei (Xidian University & National Laboratory of Science and Technology on Antennas and Microwaves, P.R. China); Xiao Wei Shi (Xidian University, P.R. China); Peiyuan Qin (CSIRO Computational Informatics, Australia); Y Jay Guo (CSIRO, Australia)
A compact ultra-wideband (UWB) power divider with unequal distribution ratio is proposed in this paper. The UWB power divider is based on the conventional unequal Wilkinson power divider with two folded shunt quarter-wavelength short-circuited stubs separated by quarter-wavelength connecting lines at each output ports. The unequal distribution ratio is achieved by adjusting impedance ratio of two output ports. In addition, a single resistor is properly placed between two output ports for improving isolation. Finally, the simulated results are presented, which are in good agreement with the measured ones.
Near-Field Characteristics of a Wideband Travelling-Wave Antenna Based on a Tapered Half-Mode Substrate-Integrated Waveguide
Nghia Nguyen-Trong (University of Adelaide, Australia); Thomas Kaufmann (The University of Adelaide, Australia); Christophe Fumeaux (The University of Adelaide, Australia)
In this paper the near-field distribution of a travelling-wave antenna based on a Half-Mode Substrate-Integrated Waveguide (HMSIW) is investigated in order to verify the guided-wave characteristics and the radiation mechanism of this antenna type. Open-ended coaxial probes are utilized to capture the electromagnetic power density at different positions along the antenna aperture. The measurement and simulation results show a good correspondence which validates the measurement technique. The presented results show fundamental differences between the tapered HMSIW antenna and the traditional uniform leaky-wave antenna (LWA). Unlike the uniform LWA, the radiation of the tapered antenna mainly happens close to cut-off position, thus small radiating effective length and an omni-directional radiation pattern are obtained.
Miniaturization of the half ring monopole antenna using self complementary method for UWB application
Mohammad Mahfuz Hussain (North South University, Bangladesh); Atiqur Rahman (North South University, Bangladesh); Christina Gomes (North South University, Bangladesh)
A novel and simple half ring monopole antenna is presented here. The proposed antenna has been fed by a 50 Ω microstrip line to provide bandwidth supporting ultra wideband (UWB) characteristics. While decreasing the physical size of the antenna, the parameters that affect the performance of the antenna have been investigated here. Using Y. Mushiake's self-complementary technique, the much desired output from the simulations has been achieved providing a compact and small size.
A Broadband Cage Antenna Optimized by Genetic Algorithm
Jingya Deng (Institute of China Electronic System Engineering Corporation, P.R. China); Xiaojun Chen (Institute of China Electronic System Engineering Corporation, P.R. China); Rui Yu (Institute of China Electronic System Engineering Corporation, P.R. China); Xiang Wen (Institute of China Electronic System Engineering Corporation, P.R. China)
An optimized design of cage antenna Using FEKO and genetic algorithm (GA) is presented. The geometry of the antenna is optimized by GA to get best VSWR and gain performances over the entire 100-400MHz band. The height of the optimized geometry of the cage antenna is only 0.75m, while the diameter is only 0.15m. The antenna can work over entire 100-400MHz with the VSWR lower than 3 and the gain higher than 1.55dBi.
Wideband Feed Systems for Radio Astronomy
John Kot (BAE Systems Australia Ltd, Australia); Christophe Granet (BAE Systems Australia Ltd, Australia); Ian Davis (BAE Systems Australia Ltd, Australia); Greg Pope (BAE Systems Australia Ltd, Australia)
Increasing requirements in radio astronomy for wide band observing, highly compact feed systems, and remote telescope operation are stretching the capability of traditional horn antenna and feed system designs. Here we describe the development of some new types of feed system for Australian and overseas radio telescopes designed to meet these requirements. These include optimised smooth-walled feed horns designed for the Australia Telescope Compact Array 22m dishes and the 100m Effelsberg dish in Germany, and a highly-compact coaxial wideband calibration feed system designed for the Australian Square Kilometre Array Pathfinder radio telescope.
Frequency-Domain Synthesis of Ultra-Wide Band Antennas with a Flat Response
Daniela Deacu (Constanta Maritime University, Romania); Razvan D. Tamas (Constanta Maritime University, Romania); Teodor Petrescu (Politehnica University of Bucharest, Romania); Teodor Petrut (Grenoble INP, France)
Antennas with a flat response over a given frequency range are commonly used in measuring systems or in spark detection and localization systems. This paper presents a synthesis approach based on a variable slope of the current distribution. The method is demonstrated by synthesizing an antenna with a quasi-constant gain over a given frequency range. The antenna resulting from synthesis was simulated, manufactured and measured in order to validate our method.
Time Domain Analysis of A Miniature Tapered-Slot UWB Antenna
Manmohan Sharma (Queen Mary University of London, United Kingdom); Clive Parini (Queen Mary University of London, United Kingdom); Akram Alomainy (Queen Mary, University of London, United Kingdom)
This paper presents the time domain study of a miniature tapered-slot ultra-wideband antenna. Firstly, the antenna geometry and frequency domain performance are briefly discussed. Subsequently, a detailed analysis of the time domain behaviour of the antenna has been provided. Through the measurements, the transfer function and group delay of the antenna system are obtained. Then, using the convolution approach, the impulse response has been investigated. The antenna has been demonstrated to have decent performance in time domain as well as frequency domain.
Broadband Printed Dipole Antenna with T-Shape Loadings
Can Wang (Huaqiao University, P.R. China); Yuehe Ge (Huaqiao University, P.R. China)
Broadband printed dipole antennas are studied in this paper. By applying a three-step microstrip transmission line as the integrated balun and symmetrically connecting a pair of identical T-shape metallic loadings on the two wings of the dipole, the bandwidth of the traditional printed dipole can be significantly enhanced. Simulations show that the proposed dipole antenna achieves a bandwidth of 80% and good radiation performance over the operating band is also obtained.
Bandwidth and Gain Enhancement of a Printed Wide Slot Antenna
Md. Samsuzzaman (Universiti Kebangsaan Malaysia, Malaysia); Mohammad Tariqul Islam (Institute of Space Science (ANGKASA) & Universiti Kebangsaan Malaysia, Malaysia); M. Habib Ullah (International Islamic University Malaysia, Malaysia)
A printed wide slot antenna design and prototyping on available low cost composite material fed by a microstrip line with a rotated square slot for bandwidth enhancement and defected ground structure for gain enhancement. I shaped microstrip line is used to excite the square slot. The rotated square slot is embedded in the middle of the ground plane and its diagonal points are implanted in the middle of strip line and ground plane. Four L shaped slots are etched in the ground plane to increase the gain. The measured results show that the proposed structure retains a wide impedance bandwidth of 88.07% which is 20 % better than reference antenna. The simulated average gain is also increased which is about 5.22 dBi with a stable radiation pattern in the entire operating band. Moreover, radiation efficiency, input impedance, and parametric studies of S11 for different design parameter are also investigated by Finite element method based simulation software HFSS.
Design of Broad Circularly Polarized Square Slot Antenna With a CPW-Fed
Wen Jiang (Xidian University, P.R. China); Shu Gong (National Laboratory of Antennas and Microwave Technology, P.R. China); Guang Fu (Xidian University, P.R. China); Yan-ping Li (Xidian University, P.R. China); Lin Yang (Xidian University, P.R. China)
The paper presents a novel design for a circularly polarized square slot antenna (CPSSA). The antenna is fed by a coplanar waveguide. An asymmetric slot on the ground is applied to create the circularly polarized wave. By adding two orthogonal stubs embedded on the microstrip feeding-line, both the impedance bandwidth and the axial ratio bandwidth of antenna are increased. The results show that 3dB axial ratio (AR) bandwidth and the impedance bandwidth with S11<-10dB are 59.2% (1.63 GHz) and 84% (2.1 GHz), respectively.
A Miniaturized, Ultra-Wideband, Circularly Polarized Spiral Antenna
Ting-Yen Shih (University of Wisconsin-Madison, USA); Nader Behdad (University of Wisconsin, USA)
A low-profile and compact, ground-plane backed spiral antenna with an ultra-wideband circularly-polarized response is presented. This antenna system is a multilayer structure composed of a center-fed modified Archimedean spiral antenna that includes a novel loading structure, a ring shaped absorber, a feeding network, and a 180° power splitter. The loading structure possesses both inductive and capacitive characteristics, which increase the equivalent electrical length of the antenna while maintaining its maximum dimensions. Using this structure, a compact spiral antenna with a diameter of 0.20λmin is obtained. This antenna is integrated into the multilayer structure along with a feeding network. An optimized ring shape absorber is used to reduce the ground effects on the performance of the antenna. The peak gain of the antenna with the feeding network is 3.94 dBic. The 3-dB axial ratio bandwidth is 155%. The VSWR < 3 bandwidth is 137%. The size of the antenna with the feeding network is 0.20λmin× 0.20λmin × 0.08λmin.
Design of a UWB Printed G-shaped Monopole Antenna using Characteristic Modes
Farhad Gozasht (University of Technology, Sydney & Sahand University of Technology, Austria); Ananda Sanagavarapu Mohan (University of Technology Sydney (UTS), Australia); Kevin Po (UTS, Australia)
This paper presents a novel G-shaped compact monopole UWB antenna printed on FR4 substrate with coplanar waveguide (CPW) feeding. The proposed antenna operates over the frequency band between 3 and 11 GHz offering a fractional impedance bandwidth of around 110 %. The antenna is designed by analysing the modal currents calculated using the characteristic mode theory. Experimental results on reflection coefficient agree well with simulations and the proposed antenna has a desirable gain and radiation pattern characteristics over the ultrawideband frequency range. The overall dimensions of the antenna are 28 × 35 × 1.6 mm3 which makes it a good candidate for many ultra-wide-band radio applications.

Metmaterial-Inspired & Miniaturized Antennas

Chair: Peiyuan Qin (CSIRO Computational Informatics, Australia)
RCS Reduction of Microstrip Antenna by Complementary Split-ring Resonators Structure
Yongtao Jia (National Laboratory of Science and Technology on Antenna and Microwaves, Xidian University, P.R. China); Ying Liu (Xidian University, P.R. China); Shuxi Gong (Xidian University, P.R. China)
In this paper, a new approach for the radar cross section (RCS) reduction of microstrip patch antenna is developed. For this purpose, complementary split-ring resonators (CSRRs) are etched on the ground of the microstrip patch antenna. A conventional microstrip patch antenna is designed with the central frequency of 5.0 GHz. The monostatic RCS of the microstrip patch antenna with CSRRs can be reduced as much as 6.3dB compared to that of the conventional antenna while maintaining almost the same radiation characters.
Dual Band Split-Ring Patch Antenna on Ceramic for Satellite Application
M. Habib Ullah (International Islamic University Malaysia, Malaysia); Mohammad Tariqul Islam (Institute of Space Science (ANGKASA) & Universiti Kebangsaan Malaysia, Malaysia); Mandeep Singh (Universiti Kebangsaan Malaysia, Malaysia); Norbahiah Misran (University Kebangsaan Malaysia, Malaysia)
Design and analysis of a split ring patch antenna on a ceramic material substrate is presented in this paper. The proposed split ring antenna designed and analyzed by using computer aided high frequency electromagnetic solver HFSS. The result shows 170 MHz (7.25 GHz - 7.42 GHz) and 173 MHz (8.0 GHz - 8.173 GHz) impedance bandwidth with 0.8 dBi and 4.67 dBi gains are achieved at two resonant frequencies 7.32 GHz and 8.07 GHz respectively. The symmetric and almost steady radiation pattern with maximum radiation efficiency of 91% and 94.03% makes the proposed antenna suitable for C and X band satellite application. The input impedance and current distribution of the proposed antenna are also analyzed.
Slotted Waveguide Antenna Array using Complimentary Split Ring Resonator Elements
Ali Daliri (RMIT University, Australia); Wayne Rowe (RMIT University, Australia); Kamran Ghorbani (RMIT University, Australia)
This paper presents the design of a 4-element array of complimentary split ring resonators (CSRRs) cut on the broad-wall of a rectangular waveguide. CSRRs have not previously been used as elements of slotted waveguide antenna (SWA) arrays. The array design is based on the parametric study on the effect of CSRR geometrical parameters on the radiation characteristics. Simulated reflection properties and realized gain patterns of the proposed CSRR-SWA array are presented and compared to that of conventional half wavelength rectangular slots. The results demonstrate the feasibility of using CSRRs in SWA arrays. It is envisaged that CSRR-SWA array could be used in multifunctional load-bearing structures to improve mechanical performance, due to their smaller size compared to conventional array elements.
Compact Dual-Band Metamaterial Antenna Based on the Dual Polarization of the Complementary Split-Ring Resonator
Mimi Aminah Wan Nordin (International Islamic University Malaysia, Malaysia); Mohammad Tariqul Islam (Institute of Space Science (ANGKASA) & Universiti Kebangsaan Malaysia, Malaysia); Norbahiah Misran (UKM, Malaysia)
This paper presents a dual-band metamaterial antenna based on the complementary split-ring resonator (CSRR). The CSRR was first studied as an individual resonator, before being made into the antenna. The metamaterial antenna is made by proximity coupling the CSRR with a thin metal strip, which serves as the feed. The strip also serves as the electric dipole that provides for the negative permittivity. By changing the alignment of the feed with respect to the axis of the CSRR, the polarization is changed, allowing for a second resonance. The footprint of the antenna at the lowest resonant frequency (600 MHz) is 0.03λ x 0.10λ x 0.001λ.
A Compact Zeroth-order Resonant Antenna Based on Modified Jerusalem Mushroom Structures
Kwok Chung (University of Western Sydney, Australia); Sarawuth Chaimool (King Mongkut's University of Technology North Bangkok, Thailand); Tanaporn Pechrkool (King Mongkut's University of Technology North Bangkok Bangkok, Thailand); Prayoot Akkaraekthalin (King Mongkut's University of Technology North Bangkok, Thailand)
In this paper, a compact zeroth-order resonant composite right/left-handed (CRLH) antenna based on modified Jerusalem mushroom structure is proposed. The modified Jerusalem cross-shaped mushroom is engineered to attain a low capacitance but a high inductance, which in turn reduce the resonant frequency and hence to fulfill the goals of antenna miniaturization with efficiency enhancement. In particular, the shunt capacitance and series inductance are tailor-made by controlling the area and width of the mushroom patch. The proposed small antenna occupies a footprint of 0.23 × 0.52 square wavelength at 3.5 GHz. From the results, the proposed antenna exhibits the omnidirectional dipole-like radiation pattern and has a realized gain of 1.15 dBi. Moreover, investigation on three different types of CRLH antenna, namely conventional mushroom, Jerusalem and modified Jerusalem is undertaken and their performances are compared.
Design of a 600 MHz Non-Foster Dipole
Wenzhi Wang (Shanghai Jiao Tong University, P.R. China); Junping Geng (Shanghai Jiaotong University, P.R. China); Ronghong Jin (Shanghai Jiao Tong University, P.R. China); Xianling Liang (Shanghai Jiaotong University, P.R. China); Richard W. Ziolkowski (University of Arizona, USA)
The design of a 600 MHz non-Foster dipole is presented. The antenna and NIC layout are modeled together using HFSS to include the mutual coupling effects between these two parts. With the formulation developed, the return loss and radiation efficiency of the non-Foster dipole can be calculated and optimized simultaneously in the circuit simulator ADS. The optimized antenna achieves a -10 dB matching bandwidth of 17.5% in simulation, with ka = 0.49. The calculated results indicate that with the non-Foster element acting as an amplifier, a radiation efficiency of over 100% within the frequency band of interest is possible.
Excitation of the Chassis Mode using Magnetic Coupling Structure
Yang Liu (Hanyang University, Korea)
In this paper we show how the chassis mode of the mobile terminal can be optimally excited through a magnetic coupling structure such that it efficiently radiates over a wide impedance bandwidth. The coupling structure is formed by a capacitively loaded slot placed at the center of the chassis. We report our investigation of the variations in the impedance band-width and efficiency when the width of the chassis and the position of the coupling structure are changed.
A Simple Planar Circularly Polarized Antenna for GPS System
Yunfei Cao (The University of Hong Kong, Hong Kong); William S. W. Cheung (The University of Hong Kong, Hong Kong); Li Liu (The University of Hong Kong, Hong Kong); Ti Yuk (The University of Hong Kong, Hong Kong)
The design of a planar right-handed circularly polarized (RHCP) antenna for the Global Positioning System (GPS) is presented in this paper. The antenna consists of two meandered monopoles, a feeding network designed using the Wilkinson power divider and a defected ground structure (DGS). These two meandered monopoles resonate at about 1.575 GHz and are placed perpendicular to each other. The Wilkinson power divider splits the input signal into two signals with equal amplitude and phase. A phase difference of 90º between the signals to the monopoles is simply obtained by using a difference in length of g/4 (g is the guide wavelength) in the two feed lines. The DGS is used to increase isolation between the two monopoles. Measured results show that the antenna has a S11 bandwidth (S11<-10dB) from 1.12 to 1.85 GHz, and axial-ratio (AR<-3dB) bandwidth from 1.53 to 1.66 GHz for GPS band. The simulated and measured S11, AR, radiation pattern, efficiency and gain are all presented.

Modelling and Simulation

Chair: Peiyuan Qin (CSIRO Computational Informatics, Australia)
DOA Estimation of Multi-band Signals Using a Compressed Sensing Technique
Tsubasa Terada (Hokkaido University, Japan); Toshihiko Nishimura (Hokkaido University, Japan); Yasutaka Ogawa (Hokkaido University, Japan); Takeo Ohgane (Hokkaido University, Japan); Hiroyoshi Yamada (Niigata University, Japan)
Much attention has been paid to direction of arrival (DOA) estimation using a compressed sensing technique. In our previous study, we have proposed a method to estimate DOAs of multi-band signals using an array antenna at a receiver. As a result, we have produced an improvement of the probability of correct estimation. Moreover, the method can deal with waves exceeding the degrees of freedom of the array. However, we have assumed that incident waves have multi-bands where complex amplitudes are the same. First, in this paper, we propose a method that allows the estimation of DOAs when only the phases at the bands are different using not the complex amplitudes but powers of the signals. Second, we extend the technique in such a way that it can estimate DOAs of the signals having different amplitudes among bands.
Identification of clusters in the fingerprinting method using power measurements
Maria Jesús Algar (University of Alcala, Spain); Oscar Gutiérrez Blanco (Universidad de Alcalá, Spain); Miguel Angel Navarro (Universidad de Alcala, Spain); José Manuel Gómez (University of Alcalá, Spain); Francisco Saez de Adana (Universidad de Alcala, Spain)
Detection method plays important role in applications of high frequencies techniques for locations systems. One of the most popular techniques is the fingerprinting that operates the relationship between signals. It is considered that in each point in the building has a unique fingerprint or received power by the access points. In this work it was made measurements into an office scenario and it was used cluster identification method to define the fingerprints. Two clustering algorithms, k-means and rek-means was implemented in order to compare both methods.
Wideband Adaptive Near/Far Field Interference Cancellation Antenna System
Reuben Shar (Thales, Australia)
This paper describes simulation results of a wideband adaptive interference cancellation antenna system that is effective for a victim antenna array in the far or near-field of an interference source. This is relevant for installations of multiple communications systems that have antennas in close proximity to one another. Electromagnetic simulation of antennas and digital signal processing techniques are applied to cancel the effect of a near-field interferer on an array of antenna elements.
On the Accuracy of the Distance-Averaging Method for Antenna Gain Measurements
Daniela Deacu (Constanta Maritime University, Romania); Razvan D. Tamas (Constanta Maritime University, Romania); Teodor Petrescu (Politehnica University of Bucharest, Romania); Ion Candel (Grenoble INP, France); Teodor Petrut (Grenoble INP, France)
We have previously proposed an indoor measuring technique for antenna gain, based on averaging a normalized transfer function over a distance range. Simulated and measured results have also been presented, in order to validate the method. In this paper, we assess the accuracy of our method by taking as a reference a traditional indoor approach, i.e., the time-gating method. A good agreement between the results issued from both techniques was noted. Further, it appears that measurements in the intermediate-field region are also possible with the distance averaging method.
Hybrid Staggered Perfectly Matched Layers in Non-Staggered Meshless Time-Domain Vector Potential Technique
Zahra Shaterian (The University of Adelaide, Australia); Thomas Kaufmann (The University of Adelaide, Australia); Christophe Fumeaux (The University of Adelaide, Australia)
In this paper a hybrid algorithm for the implementation of Perfectly Matched Layers in the meshless magnetic vector potential technique is proposed. Solving the wave equation in time-domain, the magnetic vector potential technique avoids using staggered node distributions which are needed for calculating the E and H fields when directly solving Maxwell's equations. However, implementing PMLs with stretched coordinate formulation requires auxiliary variables on a staggered node distribution. To avoid defining staggered nodes in the whole computational domain, a hybrid algorithm is proposed: The algorithm keeps a single set of nodes for the magnetic vector potential A inside the free space while it uses staggered nodes for A and auxiliary variables inside the PML. The hybrid algorithm is validated in a 2D rectangular waveguide and numerical reflection coefficients are compared for different thicknesses of the PML and for different orders of a polynomial conductivity profile inside the PML. A good agreement between theoretical results and converged solutions validates the approach.
Locating Low Frequency Coherent Sources by the Inverse Problem
Kei Hirota (Shizuoka University, Japan); Yoshihiko Kuwahara (Shizuoka University, Japan); Makoto Tanaka (Denso Corporation, Japan); Takanori Uno (Denso Corporation, Japan); Koji Ichikawa (Denso Corporation, Japan)
In order to localize unknown low frequency coherent sources, we have used an inverse problem with Tikhonov regularization. In order to perform a more accurate localization for a limited measurement data, we have used the L-curve to the regularization. The validity of the proposed method has been confirmed by experiments. From results, we can locate low frequency (850 kHz) coherent sources on the metal plate within the accuracy of 10cm.
Diffraction Loss and Phase Modulation of Terrestrial Radio-Link by Wind Turbine
Thomas Fickenscher (Helmut Schmidt University, Germany); Muhammad Bilal Raza (Helmut Schmidt University, Germany)
Coexistence of wind farms and terrestrial radio links require the investigation of suitable exclusion zones. A proper analysis of this interference including the effect of diffraction is very difficult by numerical field simulation as the problem is electrically extremely large. We propose and analyze a simple diffraction model for a wind turbine (WT) based on a one-dimensional Fresnel diffraction approach applied to tower and rotor. For the first time the dynamic behavior of the diffraction caused by the rotor blades has been investigated.
Anisotropic Uniaxial Crystal as a Substrate in Spherical Microstrip Antenna with Annular-Circular Patch and Air Gap Layer
Somayeh Komeylian, Miss (Islamic Azad University, Iran); Saeed Komeylian (Sharif University, Iran); Farrokh Hojjat-Kashani (Iran university of science and Technology, Iran)
To enhance impedance bandwidth of spherical Microstrip antenna with annular-circular patch, an air gap layer between antenna ground and substrate layer has been employed. The principle purpose of this work is to consider the effect of such layer on the impedance bandwidth and, consequently, antenna performance. To provide circular polarization, we have applied anisotropic uniaxial crystal as a substrate in spherical Microstrip antenna. Evaluating the impact of air gap layer on radiation pattern of spherical Microstrip antenna with annular-circular patch via CST program is the other goal of this correspondence for three types of substrate materials, anisotropic negative uniaxial crystal, isotropic material, and anisotropic positive uniaxial crystal.
A Three-Order Equal-Ripple Band-Pass Filtering Antenna Design Using Capacitive-Gap Coupled Asymmetrical-CPW Resonator
Chao-Shun Yang (National Chiao-Tung University, Taiwan); Ping-Hsu Chen (National Chiao Tung University Taiwan, Taiwan); Jeng Hau Lu (National Chiao Tung University, Taiwan); Jou (National Chiao Tung University, Taiwan)
In this paper, a three-order equal-ripple band-pass filter design using capacitive-gap coupled asymmetrical-CPW resonator is presented. The asymmetrical coplanar waveguide are consisted of left-side finite ground plane which is similar to a strip and the right-side ground plane which is a big ground plane. Here, we main design is the operating bandwidth (5150-5825MHz) by using the conformal mapping technique and microwave-filter theory. However, it can be an antenna candidate due to the asymmetrical-CPW effect verified by simulated results, which have the -10dB insertion loss and 70% radiation efficiency.

15:30 - 16:00

Coffee Break

16:00 - 17:15

Debate - The Future of Metamaterial Antennas

Chair: Raj Mittra (Penn State University, USA)

Debate chaired by Raj Mittra (Pennsylvania State University) with:
- Zhining Chen (National University of Singapore)
- Rick Ziolkowski (The University of Arizona)
- J. (Yiannis) Vardaxoglou (Loughborough University)
- John L. Volakis (The Ohio State University)

17:15 - 17:30

Closing Ceremony

Chair: Y Jay Guo (CSIRO, Australia)