Title :
A miniaturized broadband lumped element circulator for reconfigurable front-end system
Author :
Wada, Tomotaka ; Nakajima, Ryuji ; Obiya, Hidenori ; Ogami, Takashi ; Koshino, Masayoshi ; Kawashima, Mitsumasa ; Nakajima, Naoki
Author_Institution :
Murata Manuf. Co., Ltd., Nagaokakyo, Japan
Abstract :
A novel miniaturized broadband circulator for reconfigurable mobile handsets has been successfully developed. The circulator operating in a weak magnetic field below ferromagnetic resonance is derived by analyzing the equivalent circuit. The operating theory of the circulator has been confirmed by using the perturbation theory. The usable isolation band could be expanded to 1.71GHz to 2.17GHz, which is a very small sized 1.2 × 1.0 × H0.5 mm3 such as 1/25 compared with the conventional one, Core-Circulator is realized. The developed circulator keeps characteristics as the insertion loss of 1.1dB maximum and the TX-RX isolation of 21dB minimum which have achieved the requirements of the tunable RF front-end.
Keywords :
circulators; ferromagnetic resonance; lumped parameter networks; mobile handsets; TX-RX isolation; core-circulator; equivalent circuit; ferromagnetic resonance; frequency 1.71 GHz to 2.17 GHz; insertion loss; miniaturized broadband lumped element circulator; perturbation theory; reconfigurable front-end system; reconfigurable mobile handsets; tunable RF front-end; usable isolation band; weak magnetic field; Couplings; DH-HEMTs; Magnetic cores; Magnetic fields; Magnetic resonance imaging; Radio frequency; Admittance matrix; Lumped element microwave circuit; a weak magnetic field; circuit analysis; circulators; ferrites; microwave devices;
Conference_Titel :
Microwave Symposium (IMS), 2014 IEEE MTT-S International
Conference_Location :
Tampa, FL
DOI :
10.1109/MWSYM.2014.6848316
