The Likelihood Ratio Approach Vs. A Decision Directed Estimator for the Detection of a Transient Signal of Unknown Amplitude

摘要

The purpose of this report is to further the theory of signal detectability in underwater acoustics by comparing several approaches to the solution of the problem of detection of transient signals of unknown amplitude in noise. The two approaches given primary consideration are the optimal likelihood ratio approach and a decision-directed approach. The results of this study indicate that if one desires channel gain classification as well as detection performance, and his choice is not limited by receiver complexity or cost, he would probably choose the optimal receiver structure. However, if channel gain classification is not a necessity, and it is desirable to couple good although sub-optimal detection performance with requirements for lesser memory and structural complexity of the receiver, then a reasonable choice is the receiver structure designed for the optimal detection of a transient signal of known amplitude. (Author)