Advances in phase-only signal processing

The problem of estimating the frequencies of two sinusoids in white Gaussian noise using only the sequence of phase angles of the complex-valued data is addressed. The authors extend the single sinusoid results of Tretter (1985), Kay (1989), Lang and Musicus (1989), and Lovell et al. (1991) to two sinusoids. A computationally simple estimation scheme is proposed, which uses only phase data to estimate the frequencies, and uses envelope data to resolve the inherent ambiguity. A computer simulation was performed to compare the estimation performance of the scheme with weighted phase averaging and with Cramer-Rao lower bounds.<>