Adaptive notch smoothing revisited

The problem of extraction/elimination of a nonstationary sinusoidal signal from noisy measurements is considered. This problem is usually solved using adaptive notch filtering (ANF) algorithms. It is shown that the accuracy of signal estimates can be significantly increased if the results obtained from ANF are further processed using a cascade of appropriately designed filters. The resulting adaptive notch smoothing (ANS) algorithm can be employed to perform many offline signal processing tasks, such as elimination of sinusoidal interference from a prerecorded signal.