Title :
Linearization of high-efficiency power amplifiers using digital baseband predistortion with iterative injection
Author :
Bondar, D. ; Lopez, N.D. ; Popovic, Z. ; Budimir, D.
Author_Institution :
Wireless Commun. Res. Group, Univ. of Westminster, London, UK
Abstract :
This paper presents the linearization of a high-efficiency compressed power amplifier (PA) by iterative digital predistortion with suppression of memory effects. Iterative injection of the odd-order in-band distortion components is used to enhance the nonlinearity compensation and achieve the optimal ratio of linearization degree to computational complexity by adjusting the number of injections. Baseband equalization of the input signal minimizes memory effects. The proposed linearizer is designed within the baseband block, and does not require additional radio-frequency components. The experimental investigation is carried out with EDGE signals for an up-link PA. Up to 18 dB improvement in spectral re-growth and 10 dB reduction in a 500-kHz offset adjacent channel power ratio (ACPR) are achieved for 200-kHz EDGE signal at 880 MHz.
Keywords :
computational complexity; iterative methods; linearisation techniques; nonlinear network synthesis; power amplifiers; EDGE signal; baseband equalization; computational complexity; digital baseband predistortion; frequency 200 kHz; frequency 500 kHz; frequency 880 MHz; high-efficiency compressed power amplifiers; iterative injection; linearization; memory effect suppression; nonlinearity compensation; odd-order in-band distortion components; offset adjacent channel power ratio; radiofrequency components; spectral re-growth; Baseband; Digital signal processing; High power amplifiers; Linearization techniques; Nonlinear distortion; Polynomials; Predistortion; Table lookup; Transmitters; Wireless communication; EDGE; Iterative injection; baseband equalization; high-efficiency power amplifier; predistortion;
Conference_Titel :
Radio and Wireless Symposium (RWS), 2010 IEEE
Conference_Location :
New Orleans, LA
Print_ISBN :
978-1-4244-4725-1
Electronic_ISBN :
978-1-4244-4726-8
DOI :
10.1109/RWS.2010.5434184
