Title :
Discrete multiple tone modulation with coset coding for the spectrally shaped channel
Author :
Ruiz, Antonio ; Cioffi, John M. ; Kasturia, Sanjay
Author_Institution :
IBM Thomas J. Watson Res. Center, Hawthorne, NY, USA
fDate :
6/1/1992 12:00:00 AM
Abstract :
A discrete approach to multiple tone modulation is developed for digital communication channels with arbitrary intersymbol interference (ISI) and additive Gaussian noise. Multiple tone modulation is achieved through the concatenation of a finite block length modulator based on discrete Fourier transform (DFT) code vectors, and high gain coset or trellis codes. Symbol blocks from an inverse DFT (IDFT) are cyclically extended to generate ISI-free channel-output symbols that decompose the channel into a group of orthogonal and independent parallel subchannels. Asymptotic performance of this system is derived, and examples of asymptotic and finite block length coding gain performance for several channels are evaluated at different values of bits per sample. This discrete multiple tone technique is linear in both the modulation and the demodulation, and is free from the effects of error propagation that often afflict systems employing bandwidth-optimized decision feedback plus coset codes
Keywords :
codes; digital communication systems; fast Fourier transforms; intersymbol interference; modulation; random noise; telecommunication channels; DFT code vectors; ISI; ISI-free channel-output symbols; additive Gaussian noise; arbitrary intersymbol interference; coding gain performance; coset codes; digital communication channels; discrete Fourier transform; discrete multiple tone modulation; finite block length modulator; inverse DFT; modulator concatenation; orthogonal independent parallel subchannels; spectrally shaped channel; trellis codes; Additive noise; Convolutional codes; Demodulation; Digital communication; Digital modulation; Discrete Fourier transforms; Gaussian noise; Intersymbol interference; Modulation coding; Performance gain;
Journal_Title :
Communications, IEEE Transactions on