Theoretical analysis of detection performance and range accuracy of photon ladar

In order to investigate the detection performance and range accuracy of a laser radar using Geiger mode avalanche photodiode (GM-APD) as detector, by using the method of mathematical modeling, based on the system working principle and detection time sequence, the target detection probability was analyzed under the condition that the GM-APD detector operated under long dead-time and the echo pulse width was larger than the resolving time of the time-to-digital converter (TDC). According to the statistical theory and centroid method, the theoretical model of range accuracy was established. Using the system design parameters, the influence of the echo intensity, pulse width, noise, and echo position on the range accuracy was discussed. The results show that the stronger echo intensity, the narrower echo pulse width, the lower noise and the more front echo position result in the higher target detection probability, the lower false alarm rate and the better detection performance. Echo intensity and pulse width are the main influence factors. The stronger echo intensity and the narrower pulse width result in the higher range accuracy.