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Antenna evaluation for communications with diversity and MIMO
Rodney Vaughan
Simon Frazer University, Canada
MIMO OFDM for Wireless Communications
Ye (Geoffrey) Li
Real Time Signal Processing for Multi-Antenna Systems with Experimental Verification
Thomas Haustein
Heinrich-Hertz-Institute, Berlin
Precoding for Asymmetric MIMO-OFDM Channels for High Throughput Wireless LAN - MIMO R&D Activities at Institute for Infocomm Research
Sumei Sun
Institute of Infocomm Research, Singapore
Low Complexity Adaptive MIMO Transmission Techniques
Iain Collings
CSIRO
Narrowband UHF Measurements for MIMO Channels
Kishore Mehrotra
Tait Electronics, New Zealand
MIMO SVD in an OFDM context
Michael Faulkner
Victoria University
Antenna evaluation for communications with diversity and MIMO
Rodney Vaughan
Simon Frazer University, Canada Abstract
 The antenna is a key component in any digital communications link. The antenna gain has a direct impact on the link performance and spectral efficiency. The role of the antenna in digital communications is reviewed, and this sets the scene and motivates the research findings in this presentation. The classical directive gain and its measurement is summarised with the natural progression to the distributed gain and the diversity gain for antennas designed for multipath situations. With most links operating in multipath, multi-element antennas with high distributed gain and good diversity performance are required. Developing compact multi-element antennas with statistical performance measures means that convenient experimental evaluation techniques are required
Antenna performance evaluation is not only part of the communications system analysis and design, but it is also part of the iterative process of compact antenna design. Consequently, convenient evaluation techniques are important. Both theoretical and practical aspects are addressed for evaluating antennas for high spectral efficiency. This calls for an emphasis on the various efficiency and gain factors which feature in the multipath communications link analysis. Here, the antenna polarization efficiency becomes incorporated into the distributed gain of the antenna element and is a major difference between classical line-of sight links and diversity links for multipath.
Biography
Rodney Vaughan received his bachelor and masters degrees from the University of Canterbury, New Zealand, in 1975 and 1976 respectively, and the PhD from Aalborg University, Denmark, in 1985, all in Electrical Engineering. He joined the New Zealand Post Office (now Telecom NZ Ltd) in 1972, where he worked on a wide variety of mechanical and electrical projects including communications network analysis and telephone traffic forecasting.
In 1978, he joined the Physics and Engineering Laboratory of the NZ Department of Scientific and Industrial Research (DSIR). Here, he helped to pioneer New Zealand industrial applications of microprocessor technology through the design and development of industrial equipment ranging from abattoir hardware solutions to software protocol simulators for networks. In 1982, he received a DSIR Public Service Award for PhD study and undertook this at Aalborg University, Denmark. He was an URSI Young Scientist in 1982 and 1983 for Fields and Waves, and for Electromagnetic Theory. In 1992, he transferred to the New Zealand Institute of Industrial Research Limited (IRL, formerly part of the DSIR). He initiated and developed a research programme on communications technology and this still receives contractual funding support from the New Zealand Foundation for Research, Science and Technology. He founded the Communications Team at IRL, running several scientific and industrial research projects.
The research projects revolved around multipath communications theory (electromagnetic, line and acoustic media), diversity design, signal and sampling theory, and signal processing. Industrial projects have included the design and development of specialist antennas for personal, cellular, and satellite communications, and MIMO test bed and systems design; and also capacity theory and spatial field theory for antenna design. In 2003, he became Professor of Electrical Engineering and Sierra Wireless Senior Chair in Communications, at the School of Engineering Science, Simon Fraser University, British Columbia, Canada. His current research involves antennas, multipath propagation, space-time processing and DSP applications. Current projects are compact mammalian bio-implantable antennas; multielement antenna design and evaluation; multifaceted circularly polarized large array systems; MIMO capacity realization and precoding techniques.
He is a Fellow of the B.C Advanced System Institute, a Senior Member of the IEEE, a registered engineer in New Zealand, an URSI Correspondent, and is the New Zealand URSI Commission B (Fields and Waves) representative. Top
MIMO OFDM for Wireless Communications
Ye (Geoffrey) Li
School of Electrical and Computer Engineering, Georgia Institute of Technology Abstract
Orthogonal frequency division multiplexing (OFDM) has been shown to be an effective technique to combat multipath fading in wireless communications. The capacity of wireless communication systems can be further improved if it is used with the emerging MIMO techniques. In this tutorial, we first review classical OFDM and MIMO techniques. We then introduce MIMO-OFDM for wireless communication, including basic MIMO-OFDM systems, training design and channel estimation, and recently developed techniques, such as statistical rate allocation for layered MIMO-OFDM, subspace tracking to reduce CSI feedback, etc.
 Biography
YE (GEOFFREY) LI received his B.S.E. and M.S.E. degrees in 1983 and 1986, respectively, from the Department of Wireless Engineering, Nanjing Institute of Technology, Nanjing, China, and his Ph.D. degree in 1994 from the Department of Electrical Engineering, Auburn University, Alabama. After spending several years at AT&T Labs - Research, he joined Georgia Tech as an Associate Professor in 2000. His general research interests include statistical signal processing and wireless communications. In these areas, he has contributed over 100 papers published in referred journals and presented in various international conferences. He also has over 10 USA patents granted or pending. He once served as a guest editor for two special issues on Signal Processing for Wireless Communications for the IEEE J-SAC and served as an editorial board member of EURASIP Journal on Applied Signal Processing. He is currently serving as an editor for Wireless Communication Theory for the IEEE Transactions on Communications. He organised and chaired many international conferences, including Vice-Chair of IEEE 2003 International Conference on Communications . He has been elected as an IEEE Fellow for his contribution in signal processing for wireless communications.
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Thomas Haustein
Broadband Mobile Communication Networks Department, Heinrich-Hertz-Institute (HHI), Berlin
Abstract
 MIMO is under active consideration for 3G, Super 3G and 4G wireless
technologies. It must therefore be capable of operating in a number of
scenarios; these include single user MIMO, multiple user MISO, multiple
user SIMO and multiple user MIMO. We present findings on a number of
different algorithms for Rx decoding and Tx precoding and joint Tx and Rx
optimization. Practical performance is tested in a reprogrammable real
time experimental test-bed. The work is then extended to broadband OFDM to give Gigabit performance required for 3GPP Long Term Evolution. A number of practical issues are discussed and illustrated by experimental results obtained from measurements
Biography
Thomas Haustein was born in Berlin, Germany in 1968. He received the Dipl.-Phys. Degree in physics in 1997 from Technical-University in Berlin. In this time, he was concerned with non-linear optics and frequency conversion in rare gases. In 1997, he joined Heinrich-Hertz-Institute (HHI) in Berlin working in the field of optical WDM frequency references. Later he joined the broadband mobile communication networks department where he developed a high-speed wireless infrared transmission system for indoor communication.
Since 2000 he works in the field of multiple-input multiple-output (MIMO) radio systems for high-speed wireless communications and was involved in the development and implementation of real-time MIMO signal processing on reconfigurable hardware.
His special focus is on adaptive transmission with MIMO systems and cross-layer optimisation for cellular multi-user communication. He is engaged in preparing and conducting verifying experiments at very high data rate on a real-time experiments system and was involved in the first 1 Gbit/s transmission experiment in 2004. He received his PhD in Mobile Communications in 2006 working on MIMO systems, real-time algorithm design and real-time implementations.
Thomas has authored and co-authored about 25 conference and 4 journal papers and holds several patents.
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Precoding for Asymmetric MIMO-OFDM Channels for High Throughput Wireless LAN - MIMO R&D Activities at Institute for Infocomm Research
Sumei Sun
Institute for Infocomm Research, Singapore - Head of I 2 R's Digital Wireless-Modem Technology Lab Abstract
 The presentation will focus on I2R' s research into MIMO-OFDM systems and contributions to the IEEE802.11n standardization process. I2R has developed their own OFDM-MIMO test-bed and in the presentation, we will discuss the various precoding schemes for asymmetric MIMO-OFDM channels with more transmit than receive antennas. Their performance of capacity and diversity gains in the typical wireless LAN channels will be compared. Other system design issues, e.g., low overhead training sequence design, will be discussed in the presentation.
Biography
Sumei Sun has been with Institute for Infocomm Research (formerly known as Centre for Wireless Communications) since August 1995, and involved in R&D projects on 3G W-CDMA multiuser detection and interference cancellation, 3G W-CDMA downlink terminal algorithms, broadband wireless access transceivers, ADSL transceivers, and IEEE 802.11a compliant system designs. Since 2001, she's been leading the MIMO-OFDM effort for high data rate wireless LAN/PAN applications at I 2 R. She is co-inventor of one patent and more than ten pending patent applications, and co-author of more than fifty papers in prestigious IEEE conferences and journals. She is co-recipient of the IEEE PIMRC 2006 Best Paper Award.
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Low Complexity Adaptive MIMO Transmission Techniques
Iain Collings
CSIRO ICT Centre, Sydney Abstract
This talk presents new adaptive switching algorithms for MIMO transmission. There is a focus on both theoretical analysis and simulation performance. We are particularly interested in adapting modulation formats and multiplexing/beamforming precoders based on statistical knowledge of the channel correlation structure. We will also present a hardware demonstration of a 4x4 MIMO system, including channel sounding and IEEE802.11n-“style” transmission achieving 12 bps/Hz.
 Biography
Iain was born in Melbourne, Australia, in 1970. He received the B.E. degree with first class honours in Electrical and Electronic Engineering from the University of Melbourne in 1992, and the Ph.D. degree in Systems Engineering from the Australian National University in 1995.
Currently he is a Science Leader at the CSIRO ICT Centre, Australia. Previously Iain was an Associate Professor at the University of Sydney (1999-Aug 2005), a Lecturer at the University of Melbourne (1996-1999), and a Research Fellow in the Australian Cooperative Research Centre for Sensor Signal and Information Processing (1995).
Iain's publication list entails over 90 refereed journal and conference papers, and his research interests include: MIMO systems design; OFDM; MC-CDMA; Synchronisation; Turbo equalization; Multiuser receiver design; Interference rejection; Adaptive beamforming; Hybrid ARQ; and Adaptive resource allocation.
Iain currently serves as an Editor for the IEEE Transactions on Wireless Communications, and as a Guest Editor for the EURASIP Journal on Advanced Signal Processing. He has also served as the Vice Chair of the Technical Program Committee for IEEE Vehicular Technology Conf. (Spring) 2006, as well as serving on a number of other TPCs and organizing committees of IEEE conferences. He is also a founding organizer of the Australian Communication Theory Workshops 2000-06.
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Narrowband UHF Measurements for MIMO Channels
Kishore Mehrotra
Tait Electronics, New Zealand Abstract
Narrow band UHF channel measurements were performed to investigate the likely characteristics of the rural channels faced by the MIMO link. The channel measurement used a set of 4 TM8115 radios for transmission which each transmit a carrier with no modulation in their own time slots. The receiver consisted of 4 TM8115 radios that were frequency locked together connected to the ADCs of two mixed signal boards and digital boards from the Tait Electronics Ltd STAR platform. These used buffers to capture the outputs of the second IF stage for post processing. Tests were conducted over rural and hilly terrain for a set of 4 transmit and 4 receive antenna configurations. Post capture analysis investigated the suitability of the channels for conveying high constellation QAM modulation. Biography
Kishore Mehrotra received his Bachelor of Technology degree in Electrical Engineering from the Indian Institute of Technology, Kanpur in 1979 and PhD from the Indian Institute of Science, Bangalore, India in 1994. He worked in the Avionics Design Bureau of the Hindustan Aeronautics Limited, Hyderabad, India from 1979 to 1996 and in the Switchtec Power Systems, Christchurch from 1996 to 1998. He served as Assistant Professor in the department of Aerospace Engineering in the Indian Institute of Science, Bangalore, India from 1998 to 1999 where he taught a part of the course in Navigation, Guidance and Control. Presently he works in the Group Research of Tait Electronics Limited, Christchurch as a Senior Design Engineer. He has worked in the areas of radar tracking, digital signal processing, power electronics, control systems, hardware design, orthogonal frequency division multiplexing (OFDM) and multiple-input multiple-output (MIMO) communication systems and power amplifier linearisation, He holds patents in the areas of adaptive time division duplexing, network timing protocol and digital communication system.
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MIMO SVD in an OFDM context
Michael Faulkner
Victoria University Abstract
 Pre-coding can improve the performance of MIMO systems. MIMO – SVD is one such system that can give the channel capacity if water filling is applied correctly. Mathematically elegant, intuitive and suitable for TDD (Time Division Duplex) operation, the scheme suffers from a whole host of practical problems and compatibility issues. These include complexity, feed-back overhead, channel estimation issues, gain control variations, susceptibility to EVM performance and Doppler spread etc. The solution to some of these problems will be explained and open issues highlighted.
Biography
Professor Mike Faulkner received the B.Sc.(Eng) from London University, UK, and PhD from University of Technology Sydney, Australia. His PhD topic described DSP techniques that could correct for the non-ideal characteristics of practical RF components and sub-systems. He received the IEE(UK)'s IERE premium in 1997 for a paper on amplifier linearisation. Since then his interests have broadened to include propagation, radio systems, modulation, DSP and implementation. He is currently involved in a MIMO-OFDM project targeting the IEE802.11n standard for high throughput Wireless Local Area Networks. He is acting director of the Centre for Telecommunications and Microelectronics at Victoria University, Australia.
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