Wireless link shaping for service guarantees

Providing quality of service (QoS) guarantees on heterogeneous networks with both wireless and wireline networks involves accounting for the statistical fluctuations on wireless channels, in addition to the traffic fluctuations of interest in a purely wireline setting. We develop a detailed framework for QoS provisioning for delay constrained (real time) applications over a Rayleigh faded wireless downlink. Forward error correction (FEC) coding based link layer error recovery with interleaving is used for link shaping (i.e., for converting a link with high symbol error rates and correlations of symbol errors into a link with almost wireline characteristics). Tradeoffs between choice of code rate and interleaving depth, and the buffering used at the wireless-wireline interface, are examined. In addition to considering static bandwidth sharing as in conventional time division multiplexed (TDM) systems, we provide two mechanisms for statistical multiplexing that lead to significant capacity gains