Temperature compensation of the responsivity of avalanche photodiodes in free-space optical communication systems

In the paper, the temperature compensation of the responsivity of avalanche photodiode (APD) applied in the wireless optical communication link receiver is solved. Communication systems of this type are exposed to a wide range of operating temperatures, which markedly affect APD properties. The simplest method of compensating the temperature effects on responsivity is a corresponding change in the reverse voltage applied to the diode. The paper gives a description and an example of the application of the compensation method to the APDs of the firm Perkin Elmer. The method makes use of a temperature-dependent element in the feedback loop of switched mode power supply.