Iterative decoding for the concatenated system of VLC and STTC in presence of channel estimation errors

ABSTRACT

For wireless communications with limited bandwidth and fading channels, both source coding and MIMO techniqueare generally desired. In this paper, we consider the receiver design for a concatenated system with reversible variable length code (RVLC) and space time trellis code (STTC). The maximum a posteriori probability (MAP) decoding algorithm is adapted for both component decoders considering the facts that information are in both bit and symbol domains; systematic information are inseparable and the trellis structure of RVLC is non-symmetric. Conversion from the extrinsic information to the a priori information is also designed based on the modulation mode and mapping method. As a result, the decoding results of each component decoder can be utilized by the other component decoder iteratively so as to improve the overall decoding performance. The designed receiver is then tested for both quasi-static at and rapid fading channels when channel information is known to the receiver either perfectly or non-perfectly, which has shown significant improvement over the traditional receiver without iterative decoding.

REFERENCES

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INDEX TERMS

Primary Classification:
  E. Data
  E.4 CODING AND INFORMATION THEORY
      Subjects: Error control codes

General Terms:
Algorithms

Keywords:
RVLC, channel estimation errors, joint source and channel decoding, space time trellis code