Joint Channel Estimation And Detection Algorithm For MIMO-OFDM Systems

The requirements for the fourth generation (4G) wireless communication systems such as high data rate, high quality and high mobility make channel estimation and signal detection techniques more challenging, while the complicated transmission environment gives rise to the difficulty of channel estimation and signal detection. In this thesis, we focus on channel estimation and signal detection in MIMO-OFDM systems.In this thesis, channel estimation algorithms based on pilots are firstly studied in detail, and an improved iterative channel estimation algorithm is proposed. Simulation results show that the algorithm guarantees performance while complexity is reduced to some extent. Then we study the soft iterative detection algorithms for coded MIMO systems, and on this basis, we also propose a lower complexity iterative MMSE-SIC detection algorithms. Finally, a joint channel estimation and data detection scheme is proposed for MIMO-OFDM systems. The receiver jointly performs channel estimation, detection and decoding, with soft information iteratively provided by the decoder. One of the most attractive advantages of this scheme is that can overcome the shortcoming of traditional Turbo receivers which is sensitive to the accuracy of channel estimation. Simulation results show that the receiver significantly improves the system performance.