Design of Ground Receiver System For 500 mm Aperture Satellite-Ground Laser Communication

In order to enhance the sensitivity and resolution of the ground receiver for satellite-based laser communication, as well as simplify the acquisition process for beacon light, a 500 mm aperture ground receiver system is developed. This system is designed based on the link and design scheme of satellite-based laser communication, incorporating adaptive optics (AO) technology. It consists of four units: Cassegrain antenna with common aperture spectral detection, precision tracking tilt mirror, ultra- precision tracking AO, and AO wavefront detection. The antenna objective utilizes a coaxial Cassegrain structure combined with a refractor group to form a Kepler telescopic structure that considers volume and pupil distance requirements. To address optical axis correction issues causing pupil plane drift, a 4f system is implemented between the precise tracking tilt mirror and AO tilt mirror. Additionally, a double telecentric system is employed between the wavefront detector and deformable mirror to establish conjugate relationship and minimize axial error in wavefront detection. Optical passive methods are utilized in designing these four units to improve temperature adaptability of the system. Experimental results demonstrate that each element's wave aberration falls within 1/10 lambda (lambda=632. 8 nm) range at temperatures ranging from 10 degrees C to 30 degrees C, meeting design specifications while offering valuable references for engineering applications.