Title :
370-W Output Power GaN-FET Amplifier with Low Distortion for W-CDMA Base Stations
Author :
Wakejima, Akio ; Matsunaga, Kohji ; Okamoto, Yasuhiro ; Ota, Kazuki ; Ando, Yuji ; Nakayama, Tatsuo ; Miyamoto, Hironobu
Author_Institution :
NEC Corp., Shiga
Abstract :
High output power and low intermodulation distortion (IMD) GaN-FET amplifiers are highly sought after for W-CDMA base stations. In order to obtain high output power, we have developed a field-modulating plate GaN-FET with a high maximum drain current and a high gate-to-drain breakdown voltage. Also, in order to suppress the memory effects that obstruct digital predistortion (DPD) linearization in W-CDMA power amplifiers, we have newly developed the bias network, in which frequency-dependent impedance at the base band of multi-carrier W-CDMA signals is reduced. As a result, the GaN-FET amplifier developed for W-CDMA base stations achieves a record 370-W W-CDMA peak output power, and a low DPD linearized IMD of less than -50 dBc at the highest W-CDMA average output power of over 60 W, resulting in a significant improvement of DPD linearization not only in IM3 but also in IMS and IM7
Keywords :
III-V semiconductors; UHF power amplifiers; code division multiple access; field effect integrated circuits; gallium compounds; intermodulation distortion; wide band gap semiconductors; 370 W; FET amplifier; GaN; W-CDMA base stations; digital predistortion linearization; intermodulation distortion; memory effects; power amplifiers; Base stations; FETs; High power amplifiers; Impedance; Intermodulation distortion; Linearity; Multiaccess communication; Power amplifiers; Power generation; Predistortion; GaN-FET; W-CDMA; amplifier; base-band impedance; digital predistortion; memory effects;
Conference_Titel :
Microwave Symposium Digest, 2006. IEEE MTT-S International
Conference_Location :
San Francisco, CA
Print_ISBN :
0-7803-9541-7
Electronic_ISBN :
0149-645X
DOI :
10.1109/MWSYM.2006.249502