Constrained-beam amplitude monopulse technique for bearing estimation in passive radar with uniform circular dipole array

The paper presents an improved method for estimating the direction of arrival (DoA) of aircraft targets, based on a passive coherent location (PCL) equipped with uniform circular dipole array (UCDA). First, we use the dual-domain spatial-temporal processing (STP) for suppressing the direct path interference (DPI). Based on the STP, a constrained-beam amplitude monopulse (CBAM) technique is then developed. It is shown that the combined STP-CBAM technique has many merits, such as high bearing estimation accuracy, low complexity, and feasibility for hardware realization. Finally, the performance of the complete STP combined with CBAM bearing estimation scheme is validated using computer simulation.