LDPC码在MIMO-OFDM迭代接收系统中的性能研究

MIMO-OFDM技术是未来宽带无线通信的关键技术之一,针对未来宽带无线通信高传输速率的要求,设计了一种基于二进制和多进制LDPC码的MIMO-OFDM迭代接收系统.并且为了降低系统复杂度,只在第1次迭代时使用MMSE滤波器,在第2次及以后迭代中均使用匹配滤波器.仿真结果表明:基于二进制LDPC码的MIMO-OFDM迭代接收系统相比基于四进制LDPC码的系统收敛更快,且两者的性能均远优于基于卷积码的系统性能.

Performance research on MIMO-OFDM iterative receive system based on LDPC codes

MIMO-OFDM technique is one of the key technologies in future broadband wireless communications. To meet the requirements of high data rate wireless transmission, an MIMO-OFDM iterative receive system based on non binary and binary low-density parity check (LDPC) codes was designed. In this iterative receiver, a minimum mean square error (MMSE) filter was applied only in the first iteration, and matched filter was utilized in the second and later iterations to reduce computational complexity. Simulation results show that the MIMO-OFDM iterative receive system based on binary LDPC codes converges faster than that based on 4-ary LDPC codes slightly, and their performances are superior than that of the system using convolutional codes.