Title :
Compact coupled line quadrature hybrid coupler with enhanced balance bandwidth
Author :
Velidi, Vamsi Krishna ; Shankar, Girja ; Divyabramham, Kandimalla ; Sanyal, Subrata
Author_Institution :
Dept. Electron. & Electr. Commun. Eng., Indian Inst. of Technol., Kharagpur, Kharagpur, India
Abstract :
A single stage quadrature hybrid coupler with enhanced flat balance over a wide bandwidth is presented in this article. The present coupler is realized by replacing the transmission line sections of the conventional two-branch coupler by their equivalent parallel coupled microstrip lines (PCML). The impedance controlled wide-bandpass response produced by the PCML is utilized to achieve flat balanced response over wider bandwidth that is comparable to that of a four-branch conventional coupler. A lossless transmission line model is used to derive the design equations along with design graphs. A prototype microstrip coupler having a wide ±1.0 dB amplitude balance of 71% is fabricated at 2.4 GHz to validate theoretical predictions.
Keywords :
electric impedance; microstrip lines; transmission lines; amplitude balance; compact coupled line quadrature hybrid coupler; design equation; design graphs; enhanced balance bandwidth; enhanced flat balance; equivalent parallel coupled microstrip lines; flat balanced response; four-branch conventional coupler; impedance controlled wide-bandpass response; lossless transmission line model; microstrip coupler; single stage quadrature hybrid coupler; transmission line section; two-branch coupler; wide bandwidth; Bandwidth; Couplers; Couplings; Fabrication; Impedance; Microstrip; Power transmission lines; formatting; insert (key words); style; styling;
Conference_Titel :
Applied Electromagnetics Conference (AEMC), 2011 IEEE
Conference_Location :
Kolkata
Print_ISBN :
978-1-4577-1098-8
DOI :
10.1109/AEMC.2011.6256874