Amplitude estimation of a signal with known waveform in the presence of steering vector uncertainties

In this correspondence, we address the problem of estimating the amplitude of a signal with known waveform received on an array of sensors and we consider the case where there exist uncertainties about the spatial signature of the signal of interest. Closed-form expressions for the Crame/spl acute/r-Rao bound are derived and the respective influence of the uncertainties and the number of snapshots is studied. The maximum likelihood estimator (MLE) of the signal of interest amplitude along with the covariance matrix of the interferences and noise is also derived and an iterative algorithm is presented to obtain the ML estimates.