Study on the range precision of laser range finder based on APDs

A key application of laser range finder (LRF) is measurement of range to a target. Many modern LRFs are capable of transmitting laser pulses that are nanoseconds in duration. These pulses provide excellent range precision. However, randomness in the detected laser signals places limits on the precision. The first goal of this paper is to quantify the range precision limits of LRF. The randomness in the time between photon arrivals, which is called shot noise, is discussed. System-dependent noise sources such as dark current and detector gain variation are considered. The effect of scene-dependent parameters including background light. Finally, a noise mitigation strategy, gain equalization is described and tested on simulated.