Research on the Effect of Receiver Dead Time of the Performance Photon Counting Lidar

摘要

The receiver dead time is determined by the photon detector's dead time and the response time interval of its related processing circuit in photon counting lidar. In this paper, the influence of dead time of single pixel and multi-pixel detector on the aperture of receiving lens, ranging error and ranging accuracy is analyzed in detail. From the simulation results, different sizes of receiving lens aperture were selected for detectors with different dead time effects to match the final measurement accuracy. The multi-detector array and multi-channel signal preprocessing circuit can be used to realize independent preprocessing of each detection channel to obtain time mark data of each photon event, and then all data can be processed uniformly based on histogram statistics. With the above two methods, the noise counts of each detected pixel can be significantly reduced, and the dead time effect of each channel can be suppressed. Most importantly, he time-domain drift and ranging error of echo photons can be effectively reduced. Compared with the single pixel, the multi-pixel detector can greatly increase the maximum allowable receiving area, reduce the demand for single pulse energy of the transmitter, and facilitate the engineering implementation.