A Simple DOA Estimator Using Adjacent Pattern Power Ratio with Switched Beam Antenna

A simple DoA estimator is proposed with a switched beam antenna. The estimator is implemented with an adjacent pattern power ratio algorithm. For a single source signal, the received signal powers are measured while the antenna switches over a set of measured directive beam patterns. The pattern that exhibits the maximum received signal power is chosen. Then, the ratio between the pattern adjacent to the chosen pattern and the chosen pattern, is used to find the DoA by using a lookup table or by performing a linear regression approximation. Compared with conventional DoA estimators with switched beam antenna, the proposed algorithm allows DoA estimation with low computational cost, without sacrificing much the estimation precision. Computer simulations and experiments in an anechoic chamber are carried out to verify the proposed algorithm with a switched beam antenna: the electronically steerable parasitic array radiator (ESPAR) antenna.