In-Sector Direction-of-Arrival Estimation Using a Switched Receive Array

Abstract

Direction-of-arrival (DoA) estimation is a key operation in 5G radios, radars, and sonars. While large receive arrays enable high-resolution DoA estimates, their fully digital implementation consumes significant power. This letter demonstrates DoA estimation with a switched receive array, which consumes less power than its fully digital counterpart. The DoA is estimated in two stages. First, the sector in which the source lies is estimated by mechanically steering a wide beam. Then, the DoA within the identified sector is estimated electronically using our switched receive array. We formulate an integer program to optimize the configuration of switches at the receiver, resulting in low-aliasing artifacts within the identified sector. Using our custom 40 KHz ultrasound receive array, we demonstrate DoA estimation with our optimized switch configuration. Experiments and numerical results show that the error in the estimated DoA is smaller with our optimized switch configuration than with a randomly chosen configuration.