The influence of APD space radiation damage degradation on the laser communication system BER

Based on the radiation test of APD, the change of parameters is analyzed, and the degradation rule of performance after radiation damage is mastered. A typical IM/DD optical communication system is established. The BER and signal eye chart of the system under different dark currents and responses are obtained. The influence of APD performance parameters degradation on communication quality is further analyzed. The result shows that the increase of the dark current and the decrease of the responsivity of APD will cause the BER of the system increase. With the decrease of the responsivity, the influence of the dark current on the BER will decrease gradually, and the variation amplitude is nearly 5 orders of magnitude. With the increase of the dark current, the influence of the responsivity on the BER will change about 3 orders of magnitude. Compared with the increase of dark current, the BER is more sensitive to the decrease of responsivity.