论文信息 - Wideband 3 dB Branch Line Coupler Based on $\lambda/4$ Open Circuited Coupled Lines

Wideband 3 dB Branch Line Coupler Based on $\lambda/4$ Open Circuited Coupled Lines

This letter introduces a new 3 dB branch line coupler for wideband applications. The wideband matching property of the coupler with four λ/4 open circuited coupled lines is briefly derived. The coupler with a suspended microstrip and microstrip line structures has been simulated with HFSS and fabricated. Measurement results show insertion loss better than 3.6 dB with a power imbalance of 0.5 dB; return loss and isolation characteristics both better than 20 dB over 49% fractional bandwidth.

Jae Young Lee | Ihn Seok Kim | W. A. Arriola

[1] I. Ohta,et al. Design of Broadband CPW Branch-Line 3-dB Couplers , 2006, 2006 European Microwave Conference.

[2] T. Ho,et al. A W-band integrated power module using MMIC MESFET power amplifiers and varactor doublers , 1993 .

[3] C. G. Montgomery,et al. Principles of Microwave Circuits , 1965 .

[4] G. Riblet. A Directional Coupler with Very Flat Coupling , 1978 .

[5] Masahiro Muraguchi,et al. Optimum Design of 3-Db Branch-Line Couplers Using Microstrip Lines , 1983 .

[6] S. K. Judah,et al. Very broadband flat coupling hybrid ring , 1987 .

[7] Kai Chang,et al. Broad-band uniplanar hybrid-ring and branch-line couplers , 1993 .

[8] V. Krozer,et al. Coupled Transmission Lines as Impedance Transformer , 2007, IEEE Transactions on Microwave Theory and Techniques.

[9] Akira Enokihara,et al. Broadband branch-line coupler with arbitrary power split ratio utilizing microstrip series stubs , 2010, The 40th European Microwave Conference.

[10] R. Knochel,et al. Branchline-couplers with improved design flexibility and broad bandwidth , 1990, IEEE International Digest on Microwave Symposium.

[11] Shaofang Gong,et al. Study of wideband microstrip 90° 3-dB two-branch coupler with minimum amplitude and phase imbalance , 2008, 2008 International Conference on Microwave and Millimeter Wave Technology.