Capture Probability Modeling and Simulation in Satellite-Ground Laser Link under Vibrations

The narrow laser beam of a wireless laser link provides high gain, but its narrowness also poses challenges in physical implementation, particularly in capturing the beam. The comprehensive incorporation of vibration impact remains inadequate within the present framework employed for modeling the spatial distribution of capture probability pertaining to Gaussian beams. In this paper, we investigate how vibrations affect the probability of capturing the laser beam in a satellite-ground laser communication link. We derive a model for capture probability based on the energy detection method, taking into account several relevant factors, such as the relative position between the detector and beam, vibration, laser power, beam divergence angle, and background noise. In this paper, we thoroughly explore the principle of how vibration affects the capture probability and present numerical simulation results. Furthermore, we calculate the transmit power under required detection probability widths to provide a reference for designing the actual capture parameters.