Accuracy-Enhanced Angle-of-Arrival Finding System Using Switched Six-Port Network

Abstract

In this letter, a switched six-port (SSP) receiver is proposed for an accurate angle-of-arrival (AoA) finding system. The proposed switched six-port network consists of four antennas, two hybrid couplers, two dual-pole-dual-throw (DPDT) switches, and four power detectors. The proposed switched six-port receiver periodically selects two different antennas from four antennas, providing four different antenna spacings for a more accurate angle-of-arrival detection. As a result, we were able to achieve a smaller and more accurate AoA finding system than a conventional dual six-port receiver that uses two different antenna spacings from four antennas. For validation, the proposed method was simulated, implemented, and measured. In the measurement, the averaged root-mean-square error (RMSE) of the estimated angle over the range of -90° to 90° was 3.16° with 20 sample numbers and a signal-to-noise ratio of 15 dB.