<inline-formula> <tex-math notation="LaTeX">$X$ </tex-math> </inline-formula>-Band Reflection-Type Phase Shifters Using Coupled-Line Couplers on Single-Layer RF PCB

Abstract

In this paper, an X-band reflection-type phase shifter is presented. It is based on a single layer stub-loaded coupled line coupler loaded by two-varactor tuning circuits. This choice of coupler significantly improves on the phase shifter bandwidth achievable with a branch-line coupler, as it features lower phase imbalance across the band of interest. The proof-ofconcept prototype achieves better than 10-dB return loss across a 20 % fractional bandwidth. The phase shifter further exhibits insertion loss of 2.1 ± 1.3 dB and maximum phase shift of 392° at 10 GHz, leading to a state-of-the-art figure of merit at X-band of 115 °/dB. The occupied area is 0.25 λg 2 .

Design of Miniaturized 360° Analog Phase Shifter for Multi-Functional Transmit-Array Antenna

“…배열 안테나 시스템은 빔조향(beam-steering) 기 능이 필수적인 차세대 통신용의 필수적인 시스템으로, 최 근에 활발히 연구되고 있는 지능형 반사표면(reconfigurable intelligent surface, RIS)이나 무인항공기(unmanned aeral vehicle, UAV) 또는 저궤도(low earth orbit, LEO) 위성 통 신에 응용된다 [1]∼ [3] . 특히 높은 위상 천이 해상도를 가진 아날로그 위상 천이기 는 주로 부하 라인(loaded line) 구조 [4]∼ [6] , 결합 라인 (coupled line) 구조 [7], [8] 그리고 하이브리드 커플러(hybrid coupler)를 이용한 반사형(reflection-type) 구조 [9]∼ [14] .09 λ 0 )로 소형화된 하이브리드 커플러를 나타낸다 [15] . 본 논문은 위의 소형화된 하이브리드 커플러 구조를 활용하여 소형화된 S-대역 다기능 투과배열 안테나 단위 셀 구조에 응용을 위한 위상 천이기 설계에 대한 연구를 수행하였다.…”

A Compact Filtering Coupler with Unwanted Harmonic Rejection Using LC Composite Lines for Communication Systems Applications

“…The branch line couplers (BLCs) are widely used components in microwave and RF circuits, which have different types such as branch line, hybrid, and rat race. The coupler devices are commonly being used in balanced power amplifiers [1], Doherty power amplifiers [2,3], array antennas [4,5], and phase shifters [6]. Conventional BLCs are composed of four λ/4 transmission lines (TLs), which occupy a large area.…”