Method for obtaining CFAR detection threshold in unknown clutter background

The invention provides a method for obtaining a CFAR detection threshold in the unknown clutter background, belongs to the technical field of detection of weak radar targets and particularly relates to the technical field of non-parametric estimation and constant false alarm detection under the low signal to noise ratio condition. According to the method for obtaining the CFAR detection threshold in the unknown clutter background, the probability density function in the clutter background is estimated accurately in real time based on reference unit data according to the kernel density estimation method, then a primary detection threshold is determined according to the relation between the probability density function and upper quantiles, finally, the primary threshold is corrected by means of a threshold correction factor, and thus it is guaranteed that a set false alarm probability is maintained for a detector. In this way, the method for obtaining the CFAR detection threshold in the unknown clutter background has the advantages that universality is high, the structure is simple, the method is independent of the background, high detection performance is achieved under the small data size condition, the constant false alarm characteristic can be maintained, and the CFAR detection performance is improved.