Performance Evaluation of Wideband Microwave Direction-of-Arrival Estimation Using Luneburg Lens

In this letter, a wideband passive direction-finding (DF) system utilizing Luneburg lens is investigated. A number of detectors are placed uniformly on the surface of the equatorial plane of the Luneburg lens. Based on the received signal amplitude distribution at the detectors, the direction of arrival (DoA) is estimated using the correlation method. The root mean square errors (RMSEs) of the DoA estimation are calculated for various lens sizes, signal-to-noise ratios, and number of detectors within the frequency band from 9 to 11 GHz. To examine the proposed DF system performance, the Cramér-Rao bound on the RMSEs of the DoA estimation is derived and compared to the simulated RMSEs using the correlation method.