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Cross‐layer approach for an air interface of GEO satellite communication networks

Satellite communications play a significant role in supporting next‐generation IP‐based networks. To deploy state‐of‐the‐art satellite technologies supporting media‐rich applications, efficient utilization of radio resources and end‐to‐end Quality of Service support are mandatory requirements. The study of satellite communication constraints such as attenuation, propagation delays, fading is very critical to support user service level agreements. Adaptive resource management, advanced modulation and coding techniques and congestion control algorithms must be jointly conceived. Transport protocols need to address the impact on end‐to‐end system performance due to lower layer protocols. In this paper, we focus on cross‐layer adaptation and interaction analysis. In particular, we refer to TCP and lower layers in a geostationary‐based network architecture, assuming transport protocol enhancements such as TCP NewReno, SACK, Westwood+ and Hybla. At the physical layer, modulations and coding considered include BPSK and QPSK with convolutional coder/Viterbi decoder. The interest of this study is in evaluating the impact of two different transmission mode selection techniques: one scheme selects between the two modes on the basis of the layer 2 packer error rate performance (non‐cross‐layer method); while, the other technique selects the transmission mode on the basis of the TCP goodput performance (cross‐layer method). Our simulation results demonstrate that the second scheme permits the significant improvement of the end‐to‐end performance. Copyright © 2007 John Wiley & Sons, Ltd.