Self-adjusting sub-sample delay estimator based on fractional delaying Hilbert transform filter

In the paper a novel solution of a self-adjusting time delay estimator operating in the discrete time domain on a sinusoidal signal is presented. The proposed solution is based on an original concept of Hilbert transform filter aggregated with a fractional delay filter. The aim is to substitute a series connection of a pair of filters: the Hilbert transform filter and the filter of adjustable fractional delay, by a compound one-stage filter in order to reduce the numerical load of processing. The performance as well as the numerical complexity of our self-adjusting time delay estimator is analysed and illustrated by the results of its operation in presence of noise.