Optical Compatibility Test between Engineering Model of Laser Utilizing Communication Equipment on the Ground and the ARTEMIS Satellite in a Geostationary Earth Orbit

摘要

A ground-to-space laser communications experiment was conducted to verify the optical interface between a laser communications terminal in an optical ground station and an optical payload onboard a geostationary satellite 38,000 km away, before the launch of the satellite. The end-to-end optical characteristics such as intensity, sensitivity, wavelength, polarization, and the modulation scheme of optical signals as well as acquisition sequences of the terminals were tested under fairly good atmospheric conditions. The downlink's bit error rate was on the order of 10~(-10), in spite of atmospheric turbulence. Signal fading induced by atmospheric turbulence increased the uplink bit error rate, because the turbulent layer near the Earth's surface affects the uplink signal more than the downlink signal. The best error rate achieved was 2.5 × 10~(-5). Far-field optical antenna patterns were measured through the ground-to-satellite laser links. From these results, a more accurate dynamic link design of the optical communications link can be performed, which would be useful for system designers, especially of optical commercial systems.