A comparsion between time- and frequency-domain techniques for time-varying signal processing

This paper compares the performances of time-varying digital filters designed by time- and frequency-domain techniques. The filter performances are compared based on the mean-square difference between the actual and the desired output sequences. Theoretically, such a comparison would favor the conventional time-domain technique which, however, requires much more computation time. In this paper, numerical examples are presented to illustrate the tradeoffs between the computation time and the filter performance. We show that the frequency-domain technique is efficient but yields suboptimal results.