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大气湍流是自由空间光通信链路系统的主要限制因素。大气湍流造成光束的强度闪烁和相位起伏。因此，基于MZI- DPSK调制，考虑大、小湍流尺度引起的强度闪烁和相位噪声对误码率的影响且强度闪烁满足逆高斯分布和相位波动满足高斯分布。利用分布式天线阵接收技术，研究了大气湍流下自由空间光通信链路的误码率性能，推导了在内外尺度下，分布式天线阵接收的误码率关于相位误差的函数表达式。为了提高误码率的性能，天线阵接收采用了最大比合并技术。仿真结果得出相位误差对误码率的影响很大；内外尺度对误码率的影响可以忽略不计。采用天线阵接收可以降低系统的误码率，提高通信系统的性能，且得出天线阵接收的最佳子天线个数。“,”In free space optical link systems, atmospheric turbulence is a major limiting factor. Atmospheric turbulence will result in both intensity scintillation and phase fluctuation to the laser beam. This paper is based on MZI- DPSK modulation, considered effects of intensity scintillation and phase noise caused by large- scale and small- scale turbulence to BER, and intensity scintillation is satisfy the inverse Gaussian distribution and phase fluctuation is satisfy the Gaussian distribution. We adopt the distributed antenna array receiver technology, study the performance of bits Error Ratio in free- space optical communication through the atmospheric turbulence, and derive the average BER of antenna array as a function of the phase error considering the inner scale and outer scale effects. In order to improve the BER performance, antenna receiver adopts Maximum Ratio Combining (MRC) technology. The simulation results show that the phase error has a great impact on the error rate, and the inner scale and outer scale has a negligible impact on the error rate. Using antenna reception can reduce the error rate of the system to improve the performance of the communication system and draw the best sub- antennas number of the antenna array receiver.