"JOURNAL OF RADIO ELECTRONICS" (Zhurnal Radioelektroniki ISSN 1684-1719, N 3, 2018

contens of issues      DOI  10.30898/1684-1719.2018.3.9       full text in Russian (pdf)    

     Development of a microstrip branch-line coupler with a high degree of miniaturization


D. A. Letavin

Federal State Autonomous Educational Institution of Higher Professional Education «Ural Federal University named after the first President of Russia B.N.Yeltsin», Mira 32, Yekaterinburg 620002, Russia


The paper is received on February 25, 2018, after correction - on March 23, 2018


Abstract. In this paper the design of a compact branch-line coupler has been developed. The procedure of miniaturization consists in the use of equivalent circuits whose longitudinal dimensions are more than 2 times less as compared with the usual quarter-wave segments. For a more significant reduction in the area of ​​the coupler, the elements of equivalent circuits are located in the inner area of ​​the coupler. Using the method of etching printed circuit boards, a prototype of the proposed coupler was manufactured. The resulting design has an area of ​​75.1% less than the traditional design area, with a reduction in the relative frequency band by only 1%.

Key words: microstrip line, miniaturization, branch-line coupler. 


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For citation:

D. A. Letavin. Development of a microstrip branch-line coupler with a high degree of miniaturization. Zhurnal Radioelektroniki - Journal of Radio Electronics. 2018. No. 3. Available at http://jre.cplire.ru/jre/mar18/9/text.pdf.

DOI  10.30898/1684-1719.2018.3.9