Variance-of-instantaneous-frequency detector and its performance evaluation

摘要

The optimum detector for a determined signal in the stationary white noise background In ideal channels is a matched filter．But its performance degenerates seriously in a practical underwater acoustic system for the complexityof underwater acoustic channels．Based on the estimation of instantaneous frequency sequence and its statistical characteristics，a new type ofrobust detector，Varlance－of-Instantaneous-Frequency Detector（VIFD for short），is presented for the detection of CW pulse according to the features of underwater acousticchannels and operating environment of active sonars． It is proved through theoretical analysis，simulation and experiments that VIFD is promising for its robustness in nonstatlonary interference background and channels and that it is alsorobust for the fluctuations and decny of signal or mlsmatch caused by Doppler－frequency shift．