Title :
Design of quadrature hybrid with closely separated dual-passband using three-branch line coupler
Author_Institution :
Dept. of Comput. & Commun. Eng., Ta Hwa Inst. of Technol., Hsinchu, Taiwan
Abstract :
Design of quadrature hybrids with two closely separated bands using a three-branch line coupler is proposed. Exact design equations are derived by the fourfold even-odd mode decomposition method. For dual-band operation, the conditions of the 90° hybrid coupler are simultaneously satisfied at the two designated frequencies. Thus, the solutions can exactly give the optimum design. The realizable ranges of frequency ratio and bandwidth are also investigated. A microstrip hybrid coupler operating at 2.5/3.5 GHz for WiMAX applications is designed, fabricated and tested. Simulation and experiment results show a good agreement.
Keywords :
WiMax; microstrip directional couplers; 90° hybrid coupler; WiMAX; directional couplers; even-odd mode decomposition; frequency 2.5 GHz; frequency 3.5 GHz; microstrip hybrid coupler; separated dual-passband; three-branch line coupler; Branch line coupler; directional coupler; dualband; hybrid coupler;
Conference_Titel :
Microwave Conference Proceedings (APMC), 2010 Asia-Pacific
Conference_Location :
Yokohama
Print_ISBN :
978-1-4244-7590-2
Electronic_ISBN :
978-1-902339-22-2
