volume | PIER Journals

Abstract

Based on a novel right-angled triangle artificial line, a branch-line coupler is designed in this letter. The measured results indicate that the proposed branch-line operates at 0.975 GHz with a stopband bandwidth more than 15f_c. Here, f_c is the center frequency of the coupler. Importantly, the suppression levels in the stopband are better than 15 dB. Besides, its occupied size is about 23.18×22.5 mm², which is only 16.5% of a traditional one at the same operating band. In practice, the proposed branch-line coupler can be used in compact systems which require good high-order harmonic suppression.

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Dr. Lin Geng

Professor Guang-Ming Wang

Dr. Bin-Feng Zong

Dr. Mao-Kai Hu

Dr. Hui-Yong Zeng