Fig. 1. APD model block diagram

Fig. 2. Signal/APD gain as a function of applied operating voltage，from C30950E datasheet

Fig. 3. Bias-signal（noise 1）amplification characteristic curve of the model

Fig. 4. Circuit simulation model of APD

Fig. 5. Principle block diagram of ranging circuit model

Fig. 6. Signal waveform of standby operating status

Fig. 7. Signal waveform of ranging operating status

Fig. 8. System sensitivity test related waveform