We present a method based on maximum-likelihood estimation to calculate the threshold of the number of converted photoelectrons according to Poisson and Gaussian statistics. The calculations for detection and false-alarm probabilities are given including a proposal of error probability. An efficient approach of setting threshold according to laser flight time is discussed as the laser power decreases in propagation. Comparison of the fixed threshold and the varied threshold in Poisson and Gaussian statistics is provided. The varied threshold approach tends to keep the error probability at the lowest level. This varied threshold approach is found to have a similar effect on ranging accuracy as a threshold-fixed approach.
© 2010 Optical Society of America
SIGNAL RECOVERY AND COMPUTATIONAL SENSING AND IMAGING
Original Manuscript: April 29, 2010
Revised Manuscript: August 26, 2010
Manuscript Accepted: August 29, 2010
Published: September 22, 2010
Long Wu, Yuan Zhao, Liping Liu, Yong Zhang, and Jie Wu, "Varied threshold with laser flight time in scannerless range-gated ladar," Appl. Opt. 49, H20-H26 (2010)