Detection of performances and noise of APD detector module

In order to realize the miniaturization of the detector module of visible light communication system, a 50 cm³ temperature-controlled avalanche photodiode (APD) detector module was designed and fabricated, and the stability, temperature control effect and noise characteristics of the module were tested. The results show that the average relative deviation of photocurrent measurement of APD detector module is 0.795%; the avalanche gain and responsivity of APD detector increase with the decrease of temperature; the change of the resistance of the APD detector affects the load resistor divider so that the measured value of the excess noise factor is much larger than the true value and increases as the incident light power increases. It can be concluded that increasing the reverse bias voltage in combination with lowering the temperature control temperature is more conducive to weak light signal detection; the load resistance in the detection circuit affects the noise characteristics of the APD detector.