A compact coupler design using meandered line compact microstrip resonant cell (MLCMRC) and bended lines.

In this paper, a novel branch-line coupler using meandered line compact microstrip resonant cell (MLCMRC) and bended lines is proposed. The presented coupler works at 0.9 GHz, with good specifications. The measured values of S₁₂ and S₁₃ at 0.9 GHz are 3.2 dB and 3.3 dB, respectively, which show better than 0.3 dB insertion loss in the pass band. The measured value of S₁₄ is better than 36 dB and S₁₁ is better than 31 dB. The proposed design can eliminate 3rd and 5th harmonic with high suppression level (more than 40 dB) and reduce the size of the circuit more than 64% compared to the conventional branch-line coupler. The presented coupler has a very simple structure, which can be used in modern communication applications. [ABSTRACT FROM AUTHOR]