Design considerations of InGaAs/InP single-photon avalanche diode for photon-counting communication

In order to detect weak signal photons from background radiation, using an array of InGaAs/InP single-photon avalanche diode (SPAD) as a detector is receiving increasing interest. Firstly, the canonical structure and operation principle of SPAD are analyzed. Then, based on the basic parameters (excess bias, operating temperature, absorption region thickness, and multiplication region thickness), the integrated SPAD model of performance parameters, which combines photon detection efficiency (PDE) and dark count rate (DCR), is built. Moreover, a scheme of utilizing SPADs array to detect weak signal photons and an accurate bit error rate (BER) model of photon-counting communication with the limitation of non-ideal factors of SPAD are studied. Then, the joint model of the integrated SPAD model and the BER model is founded. According to the joint model, the design considerations of SPAD to improve the BER in photon-counting communication are investigated. In addition, in regard to a specific photon-counting communication system, the basic parameters of SPAD can be effectively optimized through the joint model.