根据广义的Huygens-Fresnel原理和修正Von Karmon谱模型，推导出了部分相干高斯-谢尔模型(GSM)光束上行传输时的平均光强解析式；获得了GSM 光束经角反射器回波后下行传输到接收端的平均光强表达式，并对其进行归一化处理；分析了GSM光束在上行-下行传输过程中平均光强的变化，且发射端和接收端在同一高度。数值分析结果表明：在大气湍流双程斜路径传输中，准直光束受湍流的影响比聚焦光束小；接收端在轴归一化光强随角反射器半径的增大先增大，最终趋于定值；在轴归一化光强随湍流外尺度增大几乎无变化，随湍流内尺度的增大而减小。

Based on the generalized Huygens-Fresnel principle and the modified Von Karmon spectrum mode, the analytic expression of mean intensity of partially coherent Gaussian- Schell model (GSM) beam, which is propagating in the atmospheric turbulence along an uplink path, is derived. The analytical formula of mean intensity of GSM beam which is echoed through corner reflector and propagated along a downlink path to the receiver is obtained and normalized. The change of mean intensity of GSM beam when it is propagating along an uplink and a downlink path is analyzed, in the case that the transmitter and the receiver are located on the same height. The results of numerical analysis show that the influence of turbulence to collimated beam is smaller than it is to focused beam, when they propagate along a double slant path in the atmospheric turbulence. On the receiver, with the increase of corner reflector radius, the axial normalized intensity first increases, and eventually tends to be constant. The axial normalized intensity decreases with the increase of turbulence inner-scale, but nearly has no change with the increase of turbulence outer-scale.