Open AccessTrans‐directional coupler with adjustable coupling coefficients and reconfigurable responses
Author(s) -
Liu Hongmei,
Fang Shaojun,
Wang Zhongbao
Publication year - 2017
Publication title -
iet microwaves, antennas and propagation
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.555
H-Index - 69
eISSN - 1751-8733
pISSN - 1751-8725
DOI - 10.1049/iet-map.2016.0877
Subject(s) - hybrid coupler , power dividers and directional couplers , coupling (piping) , materials science , physics , electronic engineering , topology (electrical circuits) , computer science , engineering , optics , electrical engineering , composite material
The study presents the theoretical and experimental study of a trans‐directional coupler with adjustable coupling coefficient and reconfigurable responses. The proposed coupler is composed of coupled lines, capacitors, varactor and inductors. By connecting different inductors through switches for the circuit implementation, and using varactor as compensation capacitor, the coupling coefficient of the proposed coupler can be easily controlled. It also features balanced output ports power distribution, high isolation, good return loss, and consistent output ports phase difference. In addition, when no inductors connected, the proposed coupler is reconfigured to be a crossover. Closed‐form design equations are derived by utilising the even–odd mode method. Based on these analytical equations, an experimental prototype is designed, fabricated and characterised. The measured results show that the coupling coefficient of the coupler can be adjusted from −3 to −40 dB with good isolation and return loss performances.