Instantaneous phase shift estimation methods

The paper presents novel simulation results from testing several different instantaneous phase shift estimation methods. The authors have optimised the methods´ parameters and have designed the numerical algorithms capable of tracking the time-varying phase shift between two signals changing in the range ±180° with frequency of up to 2 kHz. The required estimation error has been assumed to be no greater then ±0.1°. Special attention has been paid to improvement of the methods´ resistance to noise. The following algorithms have been compared: 1) analytic signal method without and with smoothing post-filters, 2) short-time Fourier transform method 3) short-time Wigner transform method, and 4) (N)LMS adaptive correlator. Standard low-pass FIR filters as well as adaptive (N)LMS and Kalman linear prediction filters have been used as post-filters in the analytic signal method