Issue No. 08 - August (1979 vol. 28)
A.R. Butz , Department of Electrical Engineering, Northwestern University
When the FFT is employed for nonrecursive digital filtering, the time required to process one block of input data, N samples long, is often approximately of the form N(logr (N) + Q), where Q = 0. Earlier results on determining optimum N have assued Q =0, becauese it has long been informally observed that typically little is to be gained by taking the value of Q > 0 into account, and because the assumption that Q = 0 permits determination of N without reference to machine dependent parameters
nonrecursive filtering, Convolution, correlation, FFT
A. Butz, "FFT Length in Digital Filtering," in IEEE Transactions on Computers, vol. 28, no. , pp. 577-580, 1979.