Point process analysis of photon limited point target detection

Under the condition of photon limited, optical signal emitted by the ultra-weak point target is discrete photon flux, which is significantly different from the imaging feature of strong light. The theoretical analysis shows that the statistical properties of photon detection events subject to the Poisson process. In this paper, a new method of choosing threshold range, which bases on the criterion that the mean value and the variance are equal in Poisson distribution, is proposed to eliminate the background noise caused by imaging device in photon images. Point process analysis method is employed in this paper to test that the counting statistics obey Poisson distribution and the time statistics obey negative exponential distribution under the condition of photon limited, which is consistent with the theoretical analysis result. The expectation occurrence-rate of ultra-weak target and the recurrence probability in the follow period can be obtained quickly and directly by the point process analysis method. These two parameters can lay the foundations for detection, forecasting and tracking.