Influence of Guard Intervals Length on Detection of Long Pulse Signals

Problems of pulse detection with unknown parameters are discussed. Detection of long pulse signals if the pulse duration exceeds duration of the detector sliding windows is considered. A widely used adaptive detector with sliding windows, known as cell averaging constant false alarm rate (CA-CFAR) detector, is investigated in detail. It is shown, that the use of long guard intervals between the analyzed sample and the sliding windows helps to significantly increase the probability of correct detection of long pulse signals. It is also shown that the use of different lengths of these guard intervals helps to increase the probability of correct detection of pulse trains in comparison with the use of identical interval lengths. The results are not limited to CA-CFAR detectors since many other types of adaptive detectors using sliding windows for noise level estimation suffer from similar problems.