Conference Paper

On interaction between loss characterization and forward error correction in wireless multimedia communication

CNRS-PRiSM Lab., Versailles Univ., France
DOI: 10.1109/ICC.2005.1494573 Conference: Communications, 2005. ICC 2005. 2005 IEEE International Conference on, Volume: 2
Source: IEEE Xplore


With the steadily growing synergy between existing heterogeneous networks, the wireless LAN appears as the de-facto wireless access network in the end-to-end multimedia services distribution chain. Unlike in the traditional wired multi-hop networks (Internet) where congestions increase persistently both delays and losses, wireless packet losses are often location- and time-varying. Particularly, WLAN communication is characterized by high bit error rates that translates into tight loss dependency. The loss process may rapidly shift between different loss correlations levels, resulting in poor forward error correction (FEC) recovery capabilities. In this paper, we address this issue by providing a combined loss model to accurately characterize the wireless loss distribution features. We use control theory guided parameter tuning in order to urge the convergence of the loss models towards seizing the instantaneous loss distribution trends. Finally, we derive a new loss-specific QoS metrics for new FEC block allocation scheme.

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Available from: Midou A. Nafaa
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    • "A. Nafaa, A. Mehaoua / Computer Networks 49 (2005) 766–786 775 MBL values are limited by 25, and larger values are not considered in our adaptive FEC since they represent transient channel behavior (fading periods ), and may dramatically increase the rate of our adaptive FEC. Further bandwidth-efficiency analysis of our model-based adaptive FEC are presented in [14]. It is clear that our streaming system provides better communication robustness through mitigating QoS degradation when consecutive loss pattern segments present substantial correlation. "
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