The difference of amplitude profile between signal and local oscillator wave will affect the heterodyne efficiency of the inter-satellite coherent optical communication system. Based on the assumption that signal and local oscillator wave have the same polarization and geometric center, and that they are phase matching, the detailed derivation of heterodyne efficiency is given when the signal has uniform or Gauss distributions, and the local oscillator wave has Airy, uniform or Gaussan distributions. The accurate analysis formulas of heterodyne efficiency are presented for some different signal and local oscillator wave distributions. The performance of heterodyne photomixing for different signal and local oscillator wave distributions are completely given by using the numerical calculations and comparative analysis method. The results indicate that the Airy+Airy and Gauss+Gauss cases have the optimal heterodyne performance, the heterodyne efficiency can reach 100%; the values of heterodyne efficiency for the Airy+Uniform and Gauss+Uniform cases are 72% and 82%, respectively, which are similar. The Airy+Gauss case is restricted by the detector radius and the Gaussian beam′s waist radius at the same time, and it is usually used in the actual system. These provide some theoretic principles for designing the inter-satellite coherent optical communication system.