雪崩光电二极管以其接收灵敏度高、响应速度快等优点,常用于扫描式激光成像系统中.由于雪崩光电二极管的工作电压随背景和温度的变化而变化,因此正确设置其工作偏压,对充分发挥接收系统的探测灵敏度是重要的.主要讨论采用恒虚警率控制法自动设置雪崩光电二极管的偏压,调整噪声门限以获得光电接收系统最佳工作状态.

Avalanched photodiode(APD) is useful in scanning laser imaging system due to their high sensitivity and fast responsibility. However, the optimal bias voltage of APD circuits is not fixed because of the changing environment conditions and temperature. It is proved that keeping APD at optimal operating state is an important condition for increasing detection sensitivity of optical receiver. Regarding this, a proper method by constant false alarm rate together with threshold detector and noise is provided. The voltages are adjusted to maintain the APD's optimal working status.