Joint estimation of delay, Doppler, and Doppler rate

The methods of inverse probability have been used by Woodward and others to obtain lower bounds on variances of radar parameter estimators. Previous results on the lower bounds of variances of delay and Doppler estimators have assumed that the reflecting object travels with a constant line of sight velocity and does not cause scintillation in the radar return. Using the inverse probability approach, this paper derives expressions for the minimum variances of estimators of the delay, Doppler, and Doppler rate of a radar return assumed to consist of a long train of pulses with independent scintillation from pulse to pulse.