本文在介绍MIMO无线通信系统模型的基础上，通过对比分析几种常用空时编码方法，选定空时分组码对信号进行编码并建立瑞利衰落信道模型，通过对两发一收及两发两收系统的仿真，研究接收天线数对系统接收信号可靠性的影响。之后进一步扩展到不同发射矩阵条件下研究多发一收系统的频谱利用率及误符号率，分析不同天线数目，不同发射矩阵条件下空时正交分组码检测算法的性能。-This paper introduced the MIMO wireless communication system model, through the comparative analysis of several commonly used method of space-time coding, grouping code for the selected space-time signal is encoded and establish Rayleigh fading channel model, through two rounds one and two rounds of closing Simulation of two closed systems, research receiving antennas to receive signals affect the reliability of the system. After further extended to study the conditions under different emission matrix of multiple spectral efficiency and symbol error rate of a closed system, analyze the different number of antennas, the performance under different emission matrix orthogonal space-time block codes condition detection algorithm.