Open AccessWideband active quasi‐circulator with tunable isolation enhancement
Author(s) -
Mung S.W.Y.,
Chan W.S.
Publication year - 2014
Publication title -
the journal of engineering
Language(s) - English
Resource type - Journals
ISSN - 2051-3305
DOI - 10.1049/joe.2013.0136
Subject(s) - circulator , wideband , port (circuit theory) , amplifier , isolation (microbiology) , insertion loss , electrical engineering , materials science , electronic engineering , computer science , optoelectronics , telecommunications , engineering , bandwidth (computing) , microbiology and biotechnology , biology
An active quasi‐circulator comprises three single‐stage distributed amplifiers (DAs), in which two are for wideband transmission while the remaining one is for wideband signal cancellation. This quasi‐circulator has wideband frequency operation and by optimising the bias current, tunable isolation enhancement between port 1 and port 3 is achieved. The experimental results show that this quasi‐circulator has insertion losses of around 0 dB, return losses better than 10 dB at each port, minimum non‐tunable isolation of around 15 dB from 0.8 to 2.2 GHz and tunable isolation of more than 40 dB between port 1 and port 3 from 0.8 to 2.2 GHz.