Title :
Power amplifier linearization with adaptive predistorter for stable IMD characteristics
Author :
Kim, Jin Young ; Kim, Jong Heon
Author_Institution :
Dept. of Radio Sci. & Eng., Kwangwoon Univ., Seoul, South Korea
Abstract :
In this paper, an adaptive predistortion linearizer is proposed and fabricated for a power amplifier implementation. In order to compensate for intermodulation distortion (IMD) drift of the predistorted power amplifier, an adaptive algorithm based on the LMS (least mean square) criterion is proposed. Improvement of 12.67 dB in 2-fone test and adjacent channel power ratio (ACPR) reduction of 6 dB is achieved for the IS-95 CDMA cellular system by applying the adaptive predistorter to power amplifier with an average power of 16 W. From the experimental results, the ACPR characteristics is maintained within a constant value less than -45 dBc when the outside temperature changes from -10 °C to 50 °C.
Keywords :
adaptive control; cellular radio; code division multiple access; intermodulation distortion; least mean squares methods; linearisation techniques; power amplifiers; radiofrequency amplifiers; IMD drift; IS-95 CDMA cellular system; RF amplifier; adaptive predistorter; adjacent channel power ratio; intermodulation distortion; least mean square criterion; linearization; power amplifier; stable IMD characteristic; Adaptive algorithm; Attenuators; Linearization techniques; Nonlinear distortion; Power amplifiers; Predistortion; RF signals; Radio frequency; Radiofrequency amplifiers; Temperature;
Conference_Titel :
Industrial Electronics Society, 2004. IECON 2004. 30th Annual Conference of IEEE
Print_ISBN :
0-7803-8730-9
DOI :
10.1109/IECON.2004.1432115
