A novel method of estimating the differential delay of a sinusoidal signal is considered. The new method utilizes the propagator method (PM) which does not require the eigen-decomposition of the cross-spectral matrix (CSM) in estimating the delay of a signal received at two separated sensors. Moreover, the proposed method would generate estimates of the signal frequencies. Such estimates of time delay and frequencies are based on the observation and/or covariance matrices. Computer simulation is performed to validate the new procedure.