DocumentCode :
49392
Title :
Nonreciprocal Components With Distributedly Modulated Capacitors
Author :
Shihan Qin ; Qiang Xu ; Wang, Yuanxun E.
Author_Institution :
Electr. Eng. Dept., Univ. of California at Los Angeles (UCLA), Los Angeles, CA, USA
Volume :
62
Issue :
10
fYear :
2014
fDate :
Oct. 2014
Firstpage :
2260
Lastpage :
2272
Abstract :
The concept of distributedly modulated capacitors (DMC) is proposed as a form of time-varying transmission-line structure offering nonreciprocal propagation and coupling characteristics. The nonreciprocity is achieved by taking advantage of the additional dimension of time-variance in the transmission-line property. The complete theory, based on: 1) the distributed parametric effect on a time-varying transmission line and 2) the distributed capacitive mixers, is presented with emphasis on the theoretical bounds of the isolation and insertion performances of DMC. Simulations are carried out and a prototype consisting of double-balanced varactor diodes on microstrip lines is implemented on a Rogers board. The measured results agree well with the theoretical derivations and the simulation results. It is thus confirmed that the DMC has great potential of being a circulator device with broadband, minimum insertion loss, and synthesizable isolation characteristics. It can be integrated into an RF system front-end that allows transmission and reception of signals at the same time and the same frequency.
Keywords :
microstrip lines; mixers (circuits); transmission lines; varactors; DMC; RF system front-end; Rogers board; circulator device; coupling characteristics; distributed capacitive mixers; distributed parametric effect; distributedly modulated capacitors; double-balanced varactor diodes; insertion performances; isolation performances; microstrip lines; minimum insertion loss; nonreciprocal components; nonreciprocal propagation; signal reception; synthesizable isolation characteristics; time-variance dimension; time-varying transmission-line structure; Capacitance; Capacitors; Circulators; Frequency modulation; Power transmission lines; Transceivers; Capacitive mixers; circulators; distributed mixers; high isolation front-end; nonlinear transmission lines; parametric amplifiers; time-varying transmission line;
fLanguage :
English
Journal_Title :
Microwave Theory and Techniques, IEEE Transactions on
Publisher :
ieee
ISSN :
0018-9480
Type :
jour
DOI :
10.1109/TMTT.2014.2347935
Filename :
6887369
Link To Document :
بازگشت