针对激光测距仪星载应用环境的特殊性, 研究了星载激光测距仪APD最佳增益控制技术。通过引入星载激光测距仪APD电流信噪比模型, 分析了影响星载激光测距仪APD信噪比的关键因素。针对某星载激光测距仪的具体应用, 展开了APD最佳增益控制技术研究, 设计了温度增益反馈控制电路, 并推导建立了温度增益数字反馈控制算法, 实验验证了控制电路及算法的正确性和良好的温度适应性。实验结果表明, 该控制电路和算法能够使得APD在-25~60 ℃温度范围下保持恒定增益, 适用于星载激光测距仪APD最佳增益控制。

Based on space applications, avalanche photodiode (APD) optimal gain control was investigated in terms of space borne laser range finder. By introducing current SNR(signal to noise ratio) model, the key factors were analyzed which mainly affects SNR of APD in space borne laser range finder. According to special application of space borne laser range finder, optimal gain control of APD was studied. Temperature feedback control circuit for APD optimal gain was designed, temperature digital feedback control algorithm for APD optimal gain was deduced, and the validity and temperature adaptability of the control circuit and the algorithm were demonstrated. It is shown from the experiment that, because of the designed control circuit and algorithm, the gain factor of APD maintains is constant in the temperature range from -25 ℃ to 60 ℃, which meets the requirement for space borne applications.