Dual-/Tri-Band Branch Line Couplers With High Power Division Isolation Using Coupled Lines

Two novel dual-/tri-band branch line couplers with high power division isolation using coupled lines are proposed in this brief. Two conventional couplers loaded with quarter-wavelength open/shorted coupled lines are adopted to realize the dual or triple bands. Each band has a high isolation due to the introduced transmission zeros. The center frequencies of the two planar couplers can be adjusted over a wide frequency band by changing the even/odd-mode characteristic impedances of the coupled lines. Two planar dual-/tri-band couplers located at 0.75/1.32 GHz, 0.69/1.0/1.4 GHz are designed and fabricated for verification. Good agreement can be observed between measured results and theoretical expectations.

[1]  Byungje Lee,et al.  Dual-Band Branch-Line Coupler With Port Extensions , 2010, IEEE Transactions on Microwave Theory and Techniques.

[2]  Mrinal Kanti Mandal,et al.  Compact dual‐band rat‐race couplers , 2008 .

[3]  Xin Gao,et al.  High Selectivity Wideband Balanced Filters With Multiple Transmission Zeros , 2017, IEEE Transactions on Circuits and Systems II: Express Briefs.

[4]  Mi Zhou,et al.  Design of tri-band branch-line couplers using novel tri-band transmission lines , 2014, Texas Symposium on Wireless and Microwave Circuits and Systems.

[5]  Tadahiro Kuroda,et al.  Analysis and Design of an 8.5-Gb/s/Link Multi-Drop Bus Using Energy-Equipartitioned Transmission Line Couplers , 2015, IEEE Transactions on Circuits and Systems I: Regular Papers.

[6]  G. Siso,et al.  Application of Composite Right/Left Handed (CRLH) Transmission Lines based on Complementary Split Ring Resonators (CSRRs) to the Design of Dual-Band Microwave Components , 2008, IEEE Microwave and Wireless Components Letters.

[7]  Jian-Xin Chen,et al.  High-Selectivity Tunable Balanced Bandpass Filter With Constant Absolute Bandwidth , 2017, IEEE Transactions on Circuits and Systems II: Express Briefs.

[8]  Shau-Gang Mao,et al.  A Novel Triple-Band Microstrip Branch-Line Coupler With Arbitrary Operating Frequencies , 2009, IEEE Microwave and Wireless Components Letters.

[9]  K.-K.M. Cheng,et al.  A novel approach to the design and implementation of dual-band compact planar 90/spl deg/ branch-line coupler , 2004, IEEE Transactions on Microwave Theory and Techniques.

[10]  Kuo-Sheng Chin,et al.  Compact Dual-Band Branch-Line and Rat-Race Couplers With Stepped-Impedance-Stub Lines , 2010, IEEE Transactions on Microwave Theory and Techniques.

[11]  R. Collin.  Foundations for microwave engineering , 1966 .

[12]  T. Itoh,et al.  Arbitrary dual-band components using composite right/left-handed transmission lines , 2004, IEEE Transactions on Microwave Theory and Techniques.

[13]  Xiu Yin Zhang,et al.  High-Efficiency Broadband Rectifier With Wide Ranges of Input Power and Output Load Based on Branch-Line Coupler , 2017, IEEE Transactions on Circuits and Systems I: Regular Papers.

[14]  Feng Lin,et al.  A Novel Tri-Band Branch-Line Coupler With Three Controllable Operating Frequencies , 2010, IEEE Microwave and Wireless Components Letters.

[15]  K.-K.M. Cheng,et al.  A novel approach to the design and implementation of dual-band compact planar 90° branch-line coupler , 2004, IMS 2004.