Title :
Turbo decoding of convolutional codes in differentially modulated OFDM transmission systems
Author :
May, Thomas ; Rohling, Hermann
Author_Institution :
Dept. of Telecommun., Tech. Univ. Hamburg-Harburg, Germany
Abstract :
Orthogonal frequency division multiplexing (OFDM) is applied in systems which transmit a high data rate over multipath fading channels in order to avoid the effort of a channel estimation and equalization required in a single carrier system. If differential modulation is applied no channel equalization is necessary at all. In this paper, the combination of differential modulation and convolutional channel coding is re-interpreted as a concatenated code in which the differential modulation is the inner code and the convolutional code the outer code. Turbo decoding is applied at the receiver resulting in a signal-to-noise ratio (SNR) gain of more than 3.5 dB compared with classical soft decision Viterbi decoding
Keywords :
OFDM modulation; concatenated codes; convolutional codes; decoding; differential detection; fading channels; multipath channels; turbo codes; DPSK; SNR gain; concatenated code; convolutional channel coding; convolutional codes; differential detection; differential modulation; differentially modulated OFDM transmission systems; high data rate transmission; inner code; multipath fading channels; orthogonal frequency division multiplexing; outer code; receiver; signal-to-noise ratio; soft decision Viterbi decoding; turbo decoding; Channel coding; Channel estimation; Concatenated codes; Convolution; Convolutional codes; Decoding; Fading; Modulation coding; OFDM modulation; Signal to noise ratio;
Conference_Titel :
Vehicular Technology Conference, 1999 IEEE 49th
Conference_Location :
Houston, TX
Print_ISBN :
0-7803-5565-2
DOI :
10.1109/VETEC.1999.778366
