- Research Article
- Open Access
Equalization of Sparse Intersymbol-Interference Channels Revisited
EURASIP Journal on Wireless Communications and Networking volume 2006, Article number: 029075 (2006)
Sparse intersymbol-interference (ISI) channels are encountered in a variety of communication systems, especially in high-data-rate systems. These channels have a large memory length, but only a small number of significant channel coefficients. In this paper, equalization of sparse ISI channels is revisited with focus on trellis-based techniques. Due to the large channel memory length, the complexity of maximum-likelihood sequence estimation by means of the Viterbi algorithm is normally prohibitive. In the first part of the paper, a unified framework based on factor graphs is presented for complexity reduction without loss of optimality. In this new context, two known reduced-complexity trellis-based techniques are recapitulated. In the second part of the paper a simple alternative approach is investigated to tackle general sparse ISI channels. It is shown that the use of a linear filter at the receiver renders the application of standard reduced-state trellis-based equalization techniques feasible without significant loss of optimality.
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Mietzner, J., Badri-Hoeher, S., Land, I. et al. Equalization of Sparse Intersymbol-Interference Channels Revisited. J Wireless Com Network 2006, 029075 (2006). https://doi.org/10.1155/WCN/2006/29075
- Communication System
- Significant Loss
- Unify Framework
- Complexity Reduction
- Equalization Technique