Wideband filter-integrated coupled-line coupler with unequal power division and inherent DC-block function

Abstract

This letter reports a novel single‐layer planar coupled‐line coupler with multiple prominent advantages. These advantages include compact size, wideband filter‐integrated coupling and transmission, unequal power division, flat phase difference, and inherent DC‐block function between two arbitrary ports. Eventually, a microstrip prototype with 7.1‐dB power‐division ratio is implemented for verification, whose fractional bandwidth of 20‐dB return loss is 58.4%. © 2016 Wiley Periodicals, Inc. Microwave Opt Technol Lett 58:121–123, 2016

A New Miniaturized Microstrip Branch-Line Coupler With Good Harmonic Suppression

“…These properties will degrade the performance of the coupler. Therefore, much work has been reported in recent years to achieve both compact design and harmonic suppression for the branch-line coupler [2][3][4][5][6][7][8][9][10][11][12][13][14][15][16].…”