Mimo-ofdm Technology In Broadband Wireless Communications Research

Future broadband wireless communication systems should be able to provide reliable high-data-rate transmissions at low cost in time and frequency selective wireless channel. Multiple Input Multiple Output (MIMO) technique, one of the most significant breakthroughs in wireless communications field offers an effective way to combat and even exploit fading. However, in order to put this novel idea into practice, more effective signal processing techniques should be developed. After near 30 year's development, Orthogonal Frequency Division Multiplexing (OFDM), proposed in 1960s, now has gained much attention with its ability to reduce system complexity. MIMO combined with OFDM has been regarded as a potential candidate for Fourth Generation (4G) mobile communication.To make a thorough understanding of MIMO-OFDM system, in this thesis the author: 1) Ananlyzed the characteristics, modeling and simulation of double-selective wideband MIMO channels; 2) Ananlyzed MIMO-OFDM architectures with various trade-off between throughputs and Quality of Service (QoS); ananlyzed the channel capacity of MIMO-OFDM systems; 3)Researched the design criteria of Space-Frequency codes (SFC) and their application in MIMO-OFDM systems, and researched into the influence of system configuration and channel type on the system performance; 4) Explored the channel estimation methods based on pilot symbol assistance to provide channel status information which are necessary for utilizing the benefit of MIMO-OFDM . The research on MIMO-OFDM offers the potential for enhanced performance, capacity and high-speed delivery of information in broadband wireless communication systems. The ultimate goal is to provide more choices for future multimedia wireless networks.