Design of an Electronically Beam Scanning Reflectarray Using Aperture-Coupled Elements

TLDR

The paper presents the design of a C‑band electronically beam‑scanning reflectarray and analyzes its loss performance. The reconfigurable element is a microstrip patch on a flexible membrane, aperture‑coupled to a transmission line loaded with two varactor diodes. The element achieves continuous 360° phase tuning with a maximum loss of 2.4 dB at 5.4 GHz, and a 30‑element breadboard steers the main beam up to 40° from broadside in the H‑plane by biasing each element.

Abstract

The design of a C-band electronically beam scanning reflectarray is presented. The reconfigurable reflectarray element consists of a microstrip patch, printed on a flexible membrane substrate, aperture-coupled to a transmission line loaded with two varactor diodes. The designed element allows continuous tuning of the reflected signal's phase over a 360deg range with a maximum loss of 2.4 dB at 5.4 GHz. The measured results on a 30-element reflectarray breadboard show that by varying the bias voltages on each element the main beam can be steered to large angles, up to 40deg from broadside in the H-plane. A loss analysis of the proposed reflectarray is also presented