非合作目标脉冲相位式激光测距仪的测程研究

对于非合作目标的中程距离测量, 从测距范围、测量精度、速度和可靠性的折衷方面来讲, 脉冲相位式激光测距法优于常规的脉冲法测距和连续波相位法测距。在脉冲相位式激光测距中提出采用连续发射的正弦调制脉冲信号提高发射激光的峰值功率以提高测程, 但发射激光的平均功率被保持很低保证了发射激光对人眼的安全。同时根据硅雪崩光电二极管(Si-APD)噪声谱密度理论, 设计了具有温度补偿和反馈电阻噪声补偿的激光测距仪前放接收模块, 详细分析了背景光, 反向高压和反馈电阻对于Si-APD接收性能的影响。实验表明：根据该方法设计的前放接收模块使测距仪接收系统获得最大信噪比, APD工作在最佳倍增状态,从而提高测距仪的探测灵敏度和最大测程。

Range Research in Pulse-Phase Laser Rangefinder with Non-Cooperative Target

In terms of range, speed, accuracy and reliability for medium range measurement with non-cooperative target, the pulse-phase laser rangefinder is superior to conventional pulsed laser rangefinder and phase-shift laser rangefinder. A high resolution ranging method is described utilizing a novel modulated waveform, hereafter referred to as coherent burst modulation. The laser is sinusoidally modulated for a brief period of time and then is off for a much longer period of time. This burst waveform has benefits compared to a continuous wave emission in that the laser peak power can be very high for measuring long distances, yet the average power can be kept low for eye safety. And more, the pre-amplified optical receiver possessing temperature compensation and feedback resistance noise compensation is designed which is based on the noise spectrum density theory of silicon avalanche-photodiode (Si-APD). The influence of background light, reverse biasing voltage and feedback resistance on the performance of APD detection circuit is analyzed in detail. The experimental results confirm that the method proposed and the optical receiver has obtained the best signal-to-noise ratio (SNR) keeping the Si-APD operating under the optimum multiplied condition and improved the detecting sensitivity and measuring distances of the pulse-phase laser rangefinder.