地面激光测距站向空间目标发射激光信号后, 其反射的回波信号达到地面站时将覆盖一定范围, 通过设置多台望远镜接收信号, 有利于提升对激光信号探测能力。根据激光雷达测距方程及信号探测概率, 分析了多望远镜信号接收系统的探测概率、提升效果以及等效接收能力。利用中国科学院上海天文台相距约60 m、口径分别为1.56 m和60 cm双望远镜系统, 通过双望远镜同时接收卫星的回波信号, 研究了双望远镜信号接收系统探测能力。相比原60 cm口径望远镜系统, 单位时间内激光回波数增加了四五倍。考虑到1.56 m口径望远镜激光测量性能, 双望远镜可等效于一台口径约1.61 m望远镜系统接收能力, 验证了多望远镜信号接收可行性和技术优势。分析了多望远镜系统对轨道高度1 000 km、直径10 cm非合作目标测量能力及所需望远镜台数, 使该测量技术在微弱信号探测与大口径望远镜激光测量中将会发挥重要作用。

The laser echo signal will cover the certain range while laser ranging to space targets through transmitting laser signal from the ground station. The number of laser echoes per unit time will be obviously increased through utilizing multi-telescopes to receive signal on ground. It′s very helpful to enhance the detection ability of measuring space targets for laser ranging system. According to laser ranging link equation and the theory of signal detecting probability, the analysis of the effect on the detecting probability of laser ranging system with multi-telescopes to receive laser signal was performed to research on the equivalent receiving ability. Based on the 1.56 m aperture of astronomical telescope about 60 m far from the 60 cm telescope at Shanghai Astronomical Observatory, Chinese Academy of Sciences, the activity of laser ranging to artificial satellites with retro-reflector was implemented to research on the detecting ability of dual-telescopes while simultaneously receiving laser echo signal. The number of laser echoes had increased by 4 to 5 times compared with the aperture of 60 cm telescope system. The effect on increasing the detecting ability of measuring space targets was obvious. Considering the laser measuring ability of 1.56 m telescope system, the equivalent receiving aperture of 1.61 m can be derived for 1.56 m/60 cm telescopes. The analysis on the detection ability of laser ranging to space targets with the orbit height of 1 000 km and the size of 10 cm and number of receiving telescopes were also performed. From the experiments the technical feasibility and advantage of multi-telescopes to receive signal are validated, which will play an important role in the weak signal detection and laser ranging in future.