信道容量是通信系统能够达到的最大传输速率,是衡量通信系统通信能力的重要指标之一。在建立了光多输入多输出(MIMO)的信道模型之后,结合脉冲位置调制(PPM)分析了光MIMO系统的平均容量和中断容量;在无背景辐射的条件下,分别推导出了有无衰落时光MIMO平均容量封闭形式的近似表达式。在相同发射功率和传输带宽条件下,得到了光MIMO技术能成倍提高现有系统信道容量的结论。通过Monte Carlo仿真实验进一步证明了理论的正确性。 Channel capacity is the maximum transmission rate that a communication system can achieve, and is one of the important indicators to measure the communication ability of a communication system. After establishing the channel model of optical multiple input multiple output (MIMO), the average capacity and the interrupt capacity of the optical MIMO system are analyzed in conjunction with the pulse position modulation (PPM). In the absence of background radiation, the existence of fading Approximate expression of closed form of time average capacity of MIMO. Under the same transmitting power and transmission bandwidth, the conclusion that optical MIMO technology can exponentially improve the channel capacity of the existing system is obtained. Monte Carlo simulation experiment further proves the correctness of the theory.