Title :
Pre-distortion-compensated up-converting OFDM power amplifier of 2W at 7GHz for digital TV broadcasting service
Author :
Abe, Tom ; Haeiwa, Kazuhisa ; Murasaki, Izuru ; Yoshid, Tetsuo ; Togashi, Jyunichi
Author_Institution :
NHK Eng. Adm. Dept., Tokyo, Japan
Abstract :
The linear- and temperature-compensated negative feedback loop of the GaAs FET SHF power amplifier operating at 7GHz greatly improved the non-linear distortion as well as the improved thermal stability in this class-A amplifier when used in the up-converting amplifier with an IF(37.5MHz) input port at -40dBm. The inter-modulation to the third harmonic frequency for the OFDM TV signals was improved by a factor of 15dB, and the equivalent CNR was improved by a factor of 9.6dB at 7GHz. The result was satisfactory. This up-converting amplifier of new type was designed to be employed in the OFDM digital TV broadcasting facilities for new terrestrial digital TV broadcasting service at 7GHz. It will be useful also for the wireless communication facilities.
Keywords :
III-V semiconductors; OFDM modulation; digital television; frequency division multiplexing; gallium arsenide; intermodulation distortion; power amplifiers; thermal stability; 2 W; 37.5 MHz; 7 GHz; FET SHF power amplifier; GaAs; OFDM TV signals; digital TV broadcasting service; harmonic frequency; linear-compensated negative feedback loop; nonlinear distortion; orthogonal frequency division multiplexing; pre-distortion-compensated up-converting OFDM power amplifier; temperature-compensated negative feedback loop; thermal stability; up-converting amplifier; wireless communication; Circuits; Digital TV; Fluctuations; Gallium arsenide; High power amplifiers; Linearity; OFDM; Operational amplifiers; Power amplifiers; TV broadcasting;
Conference_Titel :
Circuits and Systems, 2004. MWSCAS '04. The 2004 47th Midwest Symposium on
Print_ISBN :
0-7803-8346-X
DOI :
10.1109/MWSCAS.2004.1354251
