Tri-Mode Heterogeneous Integrated Beam-Switching/Van Atta/Phase-Conjugating Array Using Synthesized Transmission Lines

Abstract

With the aid of tri-operational mode synthesized transmission lines, an innovative heterogeneous integrated phased array having the functions of beam-switching and retrodirection in three individual bands is proposed and demonstrated. The key innovation is the array feeding network, capable of automatically reconfiguring its topology into three states without applying any active switch. In the low band, the feeding circuit, and hence, the entire system function as a beam-switching array using the Butler matrix for communication and positioning. In the mid and high bands, the integrated array rearranges its feeding network into pairs of isolated delay lines and becomes a Van Atta array and a phase-conjugating array, respectively, to re-radiate the signals to the direction of arrival. The core building blocks are the three-channel selector, tri-mode coupler, and diplexer, all realized by synthesized transmission lines with rigorous design formulae. The operational principle is first introduced, followed by the design and implementation of the key components. A phase compensation scheme is discussed to complete the tri-mode array design. This unique concept is experimentally verified using the radiation characteristics of the integrated array at the end of this paper.