Title :
Tunable integrated output impedance transformer on a power amplifier for 4G applications
Author :
Jato, Yolanda ; Herrera, Alfredo ; De Astis, Gianfilippo ; Huin, Francis C.
Author_Institution :
Dept. Of Commun. Eng., Univ. of Cantabria, Santander, Spain
Abstract :
This paper presents the design of a modified Ruthroff-type transmission line transformer with tuning capability. The variation of a capacitor included in the structure allows the output impedance of a power amplifier to be changed in order to prevent degradation of the efficiency due to changes in the needs of the amplifier load produced by variations in the fabrication process. The impedance transformer integrated with a WCDMA power amplifier implemented in CMOS technology has been measured obtaining high efficiency, with values of 44.7 % and 43.3 % despite the load variation and an output power of 28.9 dBm and 28.7 dBm for two different chips.
Keywords :
4G mobile communication; CMOS analogue integrated circuits; capacitors; circuit tuning; code division multiple access; impedance convertors; power amplifiers; transmission lines; wavelength division multiplexing; 4G applications; CMOS technology; Ruthroff-type transmission line transformer; WCDMA power amplifier; amplifier load; capacitor; fabrication process; load variation; tunable integrated output impedance transformer; tuning capability; Impedance; Power amplifiers; Power measurement; Power transformer insulation; Power transmission lines; Semiconductor device measurement; Transmission line measurements; Efficiency; power amplifier; transmission line transformer; tunable impedance transformer;
Conference_Titel :
Microwave Symposium Digest (IMS), 2013 IEEE MTT-S International
Conference_Location :
Seattle, WA
Print_ISBN :
978-1-4673-6177-4
DOI :
10.1109/MWSYM.2013.6697421
