Title :
Compensation of amplifier nonlinearities on wavelet packet division multiplexing
Author :
To, Kin-Fai ; Ching, P.C. ; Wong, Kon Max
Author_Institution :
Dept. of Electron. Eng., Chinese Univ. of Hong Kong, Shatin, China
Abstract :
Wavelet packet division multiplexing (WPDM) is a high-capacity, flexible and robust orthogonal multiplexing scheme in which the message signals are waveform-coded onto wavelet packet basis functions for transmission. However, WPDM suffers from severe performance degradation in the presence of high-power amplifier (HPA) nonlinearities. Data predistortion using the pth-order Volterra inverse is proposed to combat the amplifier nonlinearities in a WPDM system. A 5th-order Volterra inverse with truncated memory length is designed based on the Volterra series channel model. Computer simulations are presented to demonstrate the capability of the proposed technique in compensating amplifier nonlinearities even under system parameter discrepancies. Guidelines are also proposed for designing a wavelet filter which leads to better predistortion with the truncated Volterra inverse
Keywords :
Volterra series; compensation; digital filters; packet radio networks; packet switching; power amplifiers; transform coding; wavelength division multiplexing; wavelet transforms; HPA nonlinearities; Volterra series channel model; WPDM; amplifier nonlinearity compensation; data predistortion; high-capacity multiplexing; high-power amplifier; performance degradation; robust orthogonal multiplexing; truncated Volterra inverse; truncated memory length; waveform coding; wavelet filter; wavelet packet basis functions; wavelet packet division multiplexing; Computer simulation; Degradation; Finite impulse response filter; Guidelines; Nonlinear distortion; Nonlinear systems; OFDM; Predistortion; Robustness; Wavelet packets;
Conference_Titel :
Acoustics, Speech, and Signal Processing, 2001. Proceedings. (ICASSP '01). 2001 IEEE International Conference on
Conference_Location :
Salt Lake City, UT
Print_ISBN :
0-7803-7041-4
DOI :
10.1109/ICASSP.2001.940551
