Title :
Power and bit allocation for adaptive turbo coded modulation in OFDM systems
Author :
She, Xiaoming ; Zhou, Shidong ; Xu, Xibin ; Yao, Yan
Author_Institution :
State Key Lab on Microwave & Digital Commun., Tsinghua Univ., Beijing, China
Abstract :
An adaptive turbo coded modulation orthogonal frequency division multiplexing (OFDM) schemes with power variable over subcarriers, variable over subbands, and constant over subcarriers is proposed. Our object is to improve the overall throughput under target bit-error-rate (BER) for OFDM transmissions. Simulation results indicate that our fixed power adaptation scheme exhibits a more than 7dB signal-noise-ratio (SNR) gain relative to nonadaptive turbo coded modulation, and about 2dB additional gain can be achieved with our variable power adaptation. We also discuss the effect of the amount of subbands on throughput performance in our adaptive scheme.
Keywords :
OFDM modulation; adaptive codes; adaptive modulation; error statistics; modulation coding; subcarrier multiplexing; turbo codes; BER; OFDM systems; adaptive turbo coded modulation; bit allocation; bit-error-rate; coding; orthogonal frequency division multiplexing; power adaptation scheme; power variable; signal-noise-ratio; subcarriers; AWGN; Bit error rate; Bit rate; Convolutional codes; Digital modulation; Modulation coding; OFDM modulation; Quadrature amplitude modulation; Throughput; Turbo codes;
Conference_Titel :
Global Telecommunications Conference, 2003. GLOBECOM '03. IEEE
Print_ISBN :
0-7803-7974-8
DOI :
10.1109/GLOCOM.2003.1258370