Efficient RSS-Based DoA Estimation for ESPAR Antennas Using Multiplane SDR Calibration Approach

In this paper, we have introduced a new method to improve overall efficiency of direction-of-arrival (DoA) estimation scheme relying on received signal strength (RSS) values measured at the output port of electronically steerable parasitic array radiator (ESPAR) antenna. The proposed approach uses software-defined radio (SDR) setup and power pattern cross-correlation (PPCC) estimator involving multiple calibration planes. By placing the calibration planes using the proposed SDR-based iterative method, it has been possible to obtain more optimal form of the PPCC estimator, than originally proposed in the literature. Anechoic chamber measurements of our ESPAR antenna prototype indicate that one can keep the expected overall accuracy of DoA estimation results in a wide span of incoming signal elevation angles and, simultaneously, decrease the number of required calibration planes by more than half, which will shorten the time required for RSS-based DoA estimation process and also for the initial calibration procedure within an anechoic chamber.