Performance ofesprit in the presence of gain and phase mismatches in sensor doublets

Abstract

esprit, an acronym for Estimation of Signal Parameters via Rotational Invariance Technique, is a novel method for estimating the Directions of Arrival (doa) of plane waves using an arbitrary array of sensor doublets. However,esprit requires an identical pair of sensors in each doublet, that is the gain and phase characteristics of the sensors in a doublet have to be matched, which may be difficult to ensure in practical situations. In this paper, assuming the sources to be uncorrelated, we analyse the performance ofesprit when the gain and phase characteristics of the sensors in a doublet are not identical. It is shown that the angle estimates are unbiased and expressions are derived for the variance in the estimates ofdoa, when gain and phase mismatches exist in doublets. Computer simulation results are also presented to assert the theoretical predictions.