1. A method for detecting a target in a radar signal using space-time adaptive processing, comprising the steps: determining a test statistic T = max α max λ ∫ R f 1 ( x 0 , x 1 , … , x K  α , λ , R ) p ( R )  R max λ ∫ R f 0 ( x 0 , x 1 , … , x K  λ , R ) p ( R )  R , where x 0 is a test signal, x k are K training signals, α is an unknown amplitude of a target signal within the test signal, λ is a scaling factor, R is a covariance matrix of the training signals, and a function max returns a maximum values; and comparing the test statistic to a threshold to determine whether the target is present, or not.