Receiver performance characteristics of single-photon lidar in a strong background environment

The detection performance of the single-photon lidar (SPL) receiver is investigated as a function of optical attenuation and superconducting nanowire single-photon detector (SNSPD) parameters (detection efficiency and dead time) in a strong background environment. With detection theory, it is found that there is optimal attenuation to make detection probability the highest at a given false alarm probability, namely, optimal working conditions. Optical attenuation is proved to be required only when the background photon number is higher than a certain value; otherwise, it is not necessary. Furthermore, the performance of a Geiger-mode avalanche photodiode (GMAPD) is compared. Under optimized working conditions, the SNSPD-based receiver exhibits higher detection performance in a strong background environment than that of the GMAPD-based receiver due to shorter dead time, while in a low-noise environment, attenuation is not essential, and detection efficiency becomes the dominant factor. The theoretical result gives a reference for the SPL receiver system design to achieve optimal detection performance.