A Cross-Layer Design for Reducing Packet Loss Caused by Fading in a Mobile Ad Hoc Networ

We investigate methods for reducing packet loss in mobile ad hoc networks (MANETs) caused by the presence of fading. The modeled system employs an adaptive transmission protocol. This protocol works well when link performance is consistent and predictable, but system performance deteriorates when link quality begins to vary. A log-normal block fading model is implemented to test system performance with time-varying link performance. We propose two different methods for addressing the effects of fading. First we propose the transmission success probability (TSP) link-rate control protocol, which uses link performance measures to modify the existing adaptive transmission protocol and reduce the number of packets lost due to fading. Secondly we show that modifying the routing metric can improve system performance. We show that a cross-layer design for the TSP protocols and routing metrics that jointly considers both link and network performance results in better system performance compared to selecting each protocol separately.