Parallel-Trellis Turbo Equalizers for Sparse-Coded Transmission over SISO and MIMO Sparse Multipath Channels
| Autor: | P.J. McLane, F.K.H. Lee |
|---|---|
| Rok vydání: | 2006 |
| Předmět: |
Channel code
Theoretical computer science biology Interleaving Computer science Applied Mathematics Turbo MIMO Equalization (audio) Equalizer Adaptive equalizer Data_CODINGANDINFORMATIONTHEORY biology.organism_classification Computer Science Applications Turbo equalizer Convolutional code Turbo code Maximum a posteriori estimation Electrical and Electronic Engineering Algorithm Decoding methods Computer Science::Information Theory Rayleigh fading Communication channel |
| Zdroj: | IEEE Transactions on Wireless Communications. 5:3568-3578 |
| ISSN: | 1536-1276 |
| DOI: | 10.1109/twc.2006.256979 |
| Popis: | This paper describes a low-complexity turbo equalizer for coded sparse multipath channels whose length can span hundreds of symbol intervals. First, for single-input-single-output (SISO) systems, an existing parallel-trellis framework, which consists of a bank of identical regular trellises, is exploited to construct the maximum a posteriori (MAP) equalizer in the turbo equalizer. This MAP equalizer, when combined with prefiltering, can equalize a broad selection of sparse multipath channels, including those with nonminimum phase, by using only M-state trellises, where M is the constellation size. For multiple-input-multiple-output (MIMO) systems, a MIMO prefilter and a bank of M-state parallel-trellis MAP equalizers are deployed according to a layering structure. The total number of states needed is only NTM, where NT is the number of transmit antennae. For both SISO and MIMO systems, a class of binary convolutional and turbo codes having sparse generator polynomials are chosen as the coding schemes. These codes partially integrate channel interleaving with encoding, which allows a simple channel interleaver with low latency and memory storage requirement to be employed. The MAP decoders for these codes can also be implemented with the same parallel-trellis framework as the MAP equalizers. Overall, parallel processing is supported throughout the turbo equalizers. The amount of computational time reduction when compared to a turbo equalizer using a single-trellis MAP equalizer and decoder is proportional to the number of trellises in the parallel-trellis MAP equalizer and decoder. The performance of the parallel-trellis turbo equalizers is evaluated on static and Rayleigh fading sparse multipath channels via Monte Carlo simulations |
| Databáze: | OpenAIRE |
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