开展了基于伪随机码调制和光子计数的1550 nm光纤激光测距技术研究,研制了一套测试实验系统。为了克服常规InGaAs单光子探测器由于抑制后脉冲而导致的探测速率低的问题,系统采用离散放大光电探测器作为单光子探测器件,单光子探测速率可达100 MHz。在室温,偏置电压53 V,伪随机码序列长度81.91μs时,系统探测灵敏度可达-83.6 dBm。在不同信号功率及伪随机码序列长度情况下,对系统性能进行了测试。在伪随机码序列长度163.83μs,信号平均功率-78.6 dBm时,系统测距精度可达12.7 cm。根据实验结果,推算出一套星载条件下的系统参数。 A 1550 nm fiber laser ranging technology based on pseudo-random code modulation and photon counting was developed and a set of testing and experiment system was developed. In order to overcome the low detection rate of the conventional InGaAs single-photon detector due to suppression of the back-pulse, the system uses a discrete amplification photodetector as a single-photon detection device with a single-photon detection rate of up to 100 MHz. At room temperature, the bias voltage of 53 V, pseudo-random code sequence length of 81.91μs, the system detection sensitivity up to -83.6 dBm. The system performance was tested under different signal power and pseudo-random code sequence length. In the pseudo-random code sequence length of 163.83μs, average signal power of -78.6 dBm, the system ranging accuracy of up to 12.7 cm. According to the experimental results, a set of system parameters under on-board conditions are deduced.