anee Analysis of Closed-Form, Angle Estimator for

The 2-D DFT beamspace ESPRIT is a recently devel- oped algorithm for use in conjunction with uniform rectangular arrays (URA's) that provides automatically paired azimuth and elevation angle estimates of incident signals via a closed-form procedure. This letter investigates the statistical performance of 2D DFT beamspace ESPRIT. Expressions for the 2D DFT beamspace ESPRIT estimator variances are obtained. Samples variances of the azimuth and elevation angle estimates obtained through Monte Carlo simulations are shown to be in close agreement with theoretically predicted variances. I. INTRODUCTION HE 2-D DFT beamspace ESPRIT is a recently developed algorithm (1)-(3) for use with uniform rectangular arrays (URA's) that provides automatically paired source azimuth and elevation angle estimates via a closed-form procedure. The algorithm provides 2-D angle estimates without requiring expensive search procedures or employing ad hoc pairing procedures. Further, the algorithm does not break down if several sources have a common bearing relative to one of the array axes. Reduced dimensional beamspace processing pro- vides a further reduction in the computational demands of the algorithm. This paper investigates the statistical performance of 2-D DFT beamspace ESPRIT. Asymptotic expressions for the variances of the 2-D DFT beamspace ESPRIT DOA esti- mators are obtained. Computer simulations showing agreement between the experimental and theoretical results are presented. The performance analysis results also apply to 2-D unitary ESPRIT (2,3), the element space counterpart of 2-D DFT beamspace ESPRIT.