在无线光通信中，能见度是影响链路性能的关键因素之一。建立了不考虑大气湍流影响下的误码率(BER)模型，在此基础上，结合实际的能见度数据，运用实验仿真的方法,研究了不同能见度条件下接收孔径对无线光通信系统误码率性能的影响。结果表明：不同能见度条件下，误码率性能随接收孔径的变化趋势存在一定的差异。随着能见度值的逐渐升高，误码率值越低，说明通信系统性能越好，接收孔径对误码率的改善效果越发明显。同时，还结合工程实践中通信系统误码率性能的要求，对不同的能见度条件下，选择合适的接收孔径尺寸也进行了详细的分析，为建立实际的无线光通信链路提供理论参考依据。

Visibility is a crucial factor of affecting link performance in free space optical (FSO) communication. The bit-error rate (BER) model which does not consider the effect of turbulence is built. On this basis, the affect of receiving aperture on BER under different visibilities is studied by combing the actual visibility data and using the method of simulation. The results show that there are many differences between receiving aperture and BER under different visibilities. If the visibility is high, the BER is much lower, and the performance of system is better. The improvement of the receiving aperture on BER is obvious. At the same time, combining the requirement for BER in engineering practice, the choice of appropriate receiving aperture is discussed under different visibilities, which provides valuable theoretical reference for building the FSO communication link.