Title :
A simplified predistorter for compensation of nonlinear distortion in OFDM systems
Author :
Chang, Sekchin ; Powers, Edward J.
Author_Institution :
Dept. of Electr. & Comput. Eng., Texas Univ., Austin, TX, USA
Abstract :
This paper presents a new simplified predistortion scheme to compensate nonlinear distortion introduced by the high power amplifier (HPA) in OFDM systems. OFDM systems are susceptible to HPA nonlinearities in particular because of their large peak-to-average power ratios. Previously, a Volterra-based predistorter was suggested for compensation of HPA´s nonlinear distortion in OFDM systems. In contrast to this earlier work, our adaptive predistorter utilizes a more simplified structure. It is shown that the new simplified structure exhibits faster convergence than the previous Volterra-based predistorter. In addition, the performance of the new predistortion scheme for OFDM systems is evaluated in terms of total degradation, optimal output backoff, and BER. Simulation results also show that our predistortion scheme is more efficient in compensating the nonlinear distortion of HPAs in OFDM systems than the previous scheme
Keywords :
OFDM modulation; Volterra series; adaptive signal processing; error statistics; nonlinear distortion; power amplifiers; ADSL; BER; HPA nonlinearities; OFDM systems; Volterra series; Volterra-based predistorter; asymmetric digital subscriber line; direct and indirect learning architecture; high power amplifier; nonlinear distortion compensation; optimal output backoff; orthogonal frequency division multiplexing; peak-to-average power ratio; simplified adaptive predistorter; simulation results; Convergence; Fluctuations; High power amplifiers; Nonlinear distortion; Nonlinear filters; OFDM; Predistortion; Pulse amplifiers; Pulse shaping methods; Radio transmitters;
Conference_Titel :
Global Telecommunications Conference, 2001. GLOBECOM '01. IEEE
Conference_Location :
San Antonio, TX
Print_ISBN :
0-7803-7206-9
DOI :
10.1109/GLOCOM.2001.965993
