Reactance domain MUSIC algorithm for ESPAR antennas

Conventional adaptive array antenna processing must observe signals on all of the array antenna elements. However, because the low-cost electronically steerable parasitic array radiator (ESPAR) antenna has only a single-port output, it is not possible to observe all of the signals on the antenna elements. A direct application of most of the algorithms for the conventional adaptive array antenna is impractical. In this paper, we propose a new technique of estimation for direction-of-arrivals (DoAs) for the ESPAR antenna. This technique is based on a modification of the MUSIC (multiple signal classification) algorithm. An M-dimension vector y of the output of the antenna is obtained by using the angular diversity provided by the ESPAR antenna reactances. Then the M by M correlation matrix of the y vector is employed to estimate the MUSIC spectrum. Simulation results show that DoAs can be estimated by the reactance domain MUSIC algorithm for ESPAR antennas.