John D. Hatlestad

Phase comparison time delay estimation using wideband signals

Abstract : A method of phase comparison time delay estimation using large time-bandwidth product signals is presented. This method compares the phases of the matched filters for each channel, and it is shown that for signals with symmetric power spectra, a meaningful estimate of the time delay can be expected from this phase information and knowledge of the carrier frequency of the signal. The estimator is evaluated while operating in white Gaussian noise which is in general correlated between channels, and curves are given for the density function, mean, and variance of the estimator for various noise assumptions. The estimator is shown to take advantage of the processing gain of large time-bandwidth product signals to reduce the variance of the time delay estimate. Keywords include: Phase comparison time dealy estimator; Matched filters; Large time-bandwidth; Symmetric power spectra; and White gaussian noise.