Title :
Turbo equalization using non-systematic and recursive systematic convolutional codes
Author :
Trajkovic, Vladimir D. ; Rapajic, Predrag B.
Author_Institution :
Sch. of Electr. Eng. & Telecommun., New South Wales Univ., Sydney, NSW, Australia
Abstract :
A turbo equalization scheme using non-systematic (NSC) and recursive systematic convolutional (RSC) codes are analyzed. Although it is already known that RSC code is always better in terms of bit error rate (BER) than the best NSC code at any signal to noise ratio (SNR) [C. Berrou et al., 1993], in this paper it is shown that both types of convolutional codes, using the same generator polynomials, achieve the identical BER performance when used in the turbo equalization scheme. The simulation results are obtained over different discrete frequency selective channels introducing severe intersymbol interference (ISI) proving that the RSC codes do not outperform classical NSC codes in terms of BER for each channel in each turbo iteration. All BER results in the presence of ISI are compared with the BER results where the channel introduced no ISI so that the signal is corrupted just with additive white Gaussian noise (AWGN).
Keywords :
AWGN channels; channel coding; convolutional codes; equalisers; error statistics; intersymbol interference; maximum likelihood estimation; turbo codes; AWGN; BER; additive white Gaussian noise; bit error rate; discrete frequency selective channels; generator polynomials; intersymbol interference; nonsystematic convolutional codes; recursive systematic convolutional codes; signal to noise ratio; turbo equalization; AWGN; Bit error rate; Concatenated codes; Convolution; Convolutional codes; Decoding; Finite impulse response filter; Intersymbol interference; Signal to noise ratio; Turbo codes;
Conference_Titel :
Vehicular Technology Conference, 2003. VTC 2003-Spring. The 57th IEEE Semiannual
Print_ISBN :
0-7803-7757-5
DOI :
10.1109/VETECS.2003.1207201
