volume | PIER Journals

Abstract

Novel compact dual-band branch-line couplers are presented. By using ahalf elliptical-ring impedance stub as a basic unit, dual-band branch-line couplers are obtained. Sincea couple of half elliptical-ring impedance stubs can be folded inward to its enclosed areawithout overlap, the branch-line couplercan be miniaturized. In order to verify the effectiveness of the half elliptical-ring impedance stub, two different branch-line couplers operating at 2.4/5.8 GHz are designed, fabricated and tested. Measured results agree well with simulated ones. Compared with the stepped-impedance-stub branch-line couplers, sizes of the proposed couplers are reduced by 43% and 30%, respectively.

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Dr. Yan-Ling Han

Dr. Yong-Chang Jiao

Dr. Tao Ni

Professor Zi-Bin Weng