Two-Dimensional Beam Pattern Synthesis for Phased Arrays With Arbitrary Element Geometry via Magnitude Least Squares Optimization

Russell H Kenney,Jay W Mcdaniel,Jorge L Salazar-Cerreno

doi:10.1109/jmw.2022.3142111

Abstract

In this paper, an optimization procedure for synthesizing shaped beams with an arbitrary geometry phased array system with real-time capability is presented. The algorithm involves a combination of an arbitrary extension of the Woodward-Lawson synthesis procedure with the magnitude least-squares optimization method. This simple combination significantly reduces the optimization time, enabling real-time beam shaping in response to changing requirements on beam shape or evolving geometry in distributed arrays. The technique places no restrictions on element positioning in all three spatial dimensions and is demonstrated to accurately reproduce the desired beam shape in both angular dimensions. The algorithm is demonstrated for multiple beam cases with a large, randomly generated array in computational simulation. The applicability of the algorithm to practical phased array hardware is also demonstrated using full-wave electromagnetic simulations and measurements of a realized arbitrary phased array system using a near-field scanner in an anechoic chamber.

Highlights

A significant advantage of phased array systems is the electronic reconfigurability of the beam pattern, enabling quick changes to the direction of transmission in real-time
This paper proposes a combination of the magnitude least-squares (MLS) optimization algorithm proposed in [16] with an extension of the Woodward-Lawson synthesis technique developed by the authors to accommodate the arbitrary array geometry
Existing techniques provided in the literature are often only demonstrated for one angular dimension and seldom, if ever, are the techniques validated by measured results of a physically constructed arbitrary array. To demonstrate both the complete flexibility of the proposed technique in this article and its application in real hardware, shaped beam patterns are formed in both angular dimensions using randomly generated arbitrary arrays, and the technique is proven in practice using a physical arbitrary array measured using a near-field scanner

Summary

INTRODUCTION

A significant advantage of phased array systems is the electronic reconfigurability of the beam pattern, enabling quick changes to the direction of transmission in real-time. KENNEY ET AL.: TWO-DIMENSIONAL BEAM PATTERN SYNTHESIS FOR PHASED ARRAYS WITH ARBITRARY ELEMENT GEOMETRY least-squares [14], and linear programming [15], among others These optimization procedures often lead to large computational burdens, and as such they do not lend themselves to real-time beam shaping applications. Existing techniques provided in the literature are often only demonstrated for one angular dimension and seldom, if ever, are the techniques validated by measured results of a physically constructed arbitrary array To demonstrate both the complete flexibility of the proposed technique in this article and its application in real hardware, shaped beam patterns are formed in both angular dimensions using randomly generated arbitrary arrays, and the technique is proven in practice using a physical arbitrary array measured using a near-field scanner.

ALGORITHM DESCRIPTION

WOODWARD-LAWSON SYNTHESIS

MAGNITUDE LEAST SQUARES OPTIMIZATION

EM SIMULATION AND MEASURED RESULTS

NEAR-FIELD MEASUREMENTS

CONCLUSION