volume | PIER Journals

Abstract

An extremely compact branch-line coupler operating at 900 MHz is presented without the use of viaholes, multilayered technique, or air-bridged. The technique presented here uses the concept of fractals to load a coupled transmission-line in order to realize a compact quarter-wavelength transmission-line, which forms the couplers arms. It is shown that the proposed branch-line coupler's performance is analogous to a conventional branch-line coupler with the benefit of substantially reduced physical dimensions by a factor of 78%. The measured result of the fabricated microstrip branch-line coupler is compared with the simulation data. The agreement of the measurement and simulated confirms the theory and validates the proposed coupler design.

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Mr. Mehdi Nosrati

Prof. Bal Singh Virdee