Recent advances in rapid frequency estimation

There are two main types of frequency estimator—the traditional, based on FFT's, and the more modern, based on linear filtering. Statistical and computational efficiency usually have to be traded off against each other. Typically the filter-based estimators are statistically grossly inefficient. This paper discusses the extension of the Quinn–Fernandes (filter-based, statistically optimal) technique to complex-valued signals, and the use of zero-padding to improve the statistical efficiency of the Fourier transform interpolative (FTI) estimator to statistical near-optimality.