TABLE OF CONTENTS Recent years have witnessed an explosive growth of interest in studying and using multiple antenna techniques for wireless communication systems. Such a trend is motivated by the fact that several of the specifications foreseen for future wireless systems appear to be difficult, if not impossible, to fulfill with conventional single antenna systems. It is widely accepted that multiple antennas have the potential to increase the achievable data throughput, to enhance link quality (BER, QoS), and to increase cell coverage and network capacity, among others. Such a promising array of enhancements has contributed to speeding up the development in the field, both at academic levels, where countless techniques are developed, and in the industry, where solutions based on these techniques are being rapidly adopted in real systems.
Multiple transmit and receive antennas can be combined with various multiple access techniques such as TDMA, CDMA, and OFDM to improve the capacity and reliability of communications. Multiple-input multiple-output (MIMO) communication systems are regarded as an effective solution for future high-performance wireless networks. The use of multiple antennas at transmitter and receiver, popularly known as MIMO, is a promising cost-effective technology that offers substantial leverages in making the anticipated 1-Gbps wireless links a reality.
Several efforts are currently underway to build non-line-of-sight (NLOS) broadband wireless systems. A MIMO wireless system (physical layer and MAC layer technology) using OFDM modulation for NLOS environments was successfully developed by NTT DoCoMo. In mobile access, there is an effort under the ITU working group to...
