一种非线性信道MIMO-OFDM系统性能改进算法

摘要

Multiple -Input Multiple- Output Orthogonal Frequency Division Multiplexing (MIMO-OFDM) can improve the system transmission performance in frequency selective fading channels. Like OFDM systems, the high Peak-to-Average Power Ratio (PAPR) is a serious disadvantage of MIMO-OFDM. An orthogonal partial transmit sequence (PTS) based PAPR reduction algorithm for MIMO -OFDM systems with space time block coding (STBC) is proposed in this paper. Using this algorithm and the Fourier transform, nearly half of the system complexity is reduced and only one series of side informa-tion is needed by adjusting the order of space - time coding and the baseband quadrature modulation to the two transmitters. Bit error rate (BER) performance of the proposed algorithm through rayleigh fading chan-nels is simulated with the high power amplifier (HPA) non - linearity model. Simulation resuhs prove the effectiveness of the proposed method.%多输入多输出正交频分复用(MIMO-OFDM)可以提高系统在频率选择性衰落信道的传输性能.与OFDM系统一样,MIMO-OFDM系统也存在高峰值平均功率比(PAPR)的问题.为此,提出了一种降低空时分组编码MIMO-OFDM系统PAPR的正交部分传输序列算法,运用这种算法,利用傅里叶变换的性质,通过调整空时编码与基带正交调制的顺序,对两天线发射端,可以降低算法近一半的复杂度,且可以减少一半的边信息.利用高功率放大器的非线性模型,得到了瑞利衰落信道下PAPR降低后系统的误码率性能.仿真结果证明了该方法的有效性.