Robustness of a CFAR detector to errors on the signal

The authors deals with the robustness (insensitivity) to errors on the assumptions of the receiver structure for the detection of a signal in nonstationary Gaussian noise with fluctuating power. The structure of this operation is a matched filter divided by a noise-amplitude estimate. He uses the maximum-likelihood estimate of the noise amplitude, calculated under the hypothesis H₁, so it has the noise-alone reference (NAR) property. He studies the performance of this receiver structure when there is a mismatch between the expected signal and the received one. Two cases of uncertainties on the signal are treated. An error in the estimate of the received signal has only a small effect on the NAR property of the estimate of the noise power. When there is a frequency shift between the expected and the received signal, the whole structure is shown to perform well