Phased Array With Improved Beamforming Capability via Use of Double Phase Shifters

TL;DR

This paper introduces a novel double phase shifter design for passive electronically scanned arrays, significantly enhancing beamforming flexibility by controlling both magnitude and phase of antenna weights, even with low phase resolution.

Contribution

It proposes a new DPS-based method to increase degrees of freedom in PESA, enabling complex beamformer approximation and improved beampattern control.

Findings

Significant beamforming improvement demonstrated in simulations.

Effective approximation of complex beamformers with low phase resolution.

Enhanced beampattern flexibility compared to traditional PESA.

Abstract

The passive electronically scanned array (PESA) is widely used due to its simple structure and low cost. {Its antenna weights have unit modulus and thus, only the weights phases can be controlled. PESA has limited degrees of freedom for beampattern design, where only the direction of the main beam can be controlled.} In this paper we propose a novel way to improve the beamforming capability of PESA by endowing it with more degrees of freedom via the use of double phase shifters (DPS). By doing so, both the magnitude and the phase of the antenna weights can be controlled, allowing for more flexibility in beampattern design. We also take into account the physical resolution limitation of phase shifters, and propose a method to approximate a given complex beamformer using DPS. Simulation results indicate significant beamforming improvement even at low phase resolution.