Channel state modeling and performance evaluation of DVB-S2X based broadband land mobile satellite communication systems

摘要

The increasing demand of highly efficient wireless communication systems that supports high data-rates has been manifest with the fifth-generation (5G) system of systems. Satellite communications systems are to play significant role in supporting this system in terms of significant capacity enhancement, in addition to its ability to serve area where the terrestrial infrastructure is unable to provide services. The DVB-S2 standards are the candidates that will support this quest. The extension of the second generation of the DVB-S2X has further justified this advantage by incorporating higher modulation and coding schemes (MODCODs) such as the 64-APSK, 128-APSK, and 256-APSK. However, with the increasing utilization of on-the-move applications and services, the classical limitations of the satellite links in a mobile environment pose a problem to the seamless realization of capacity. These problems include signal fading due to path blockage, multipath propagation, and shadowing. A realistic mobile satellite channel has been modeled in MATLAB¯ using realistic terrain data which is processed in Systems Tool Kits simulator (STK) in order to determine the satellite-receiver access time leading to the determination of the Markovian Transition Matrix used for channel state condition. The performance of a good selection of DVB-S2X MODCODs has been presented and the new mobile channel has been used to test the effect on mobility on system performance. The result indicated that the mobility of the earth station causes degradation to the link performance, with scenarios of higher values of Rician K-factor, denoting the dominance of line-of-sight (LOS) being the best. Therefore, the need for further highly efficient receiver processing and optimal thresholds switching techniques that can support mobile channels in terms of high data-rate and availability is more than a prerequisite for the satellite component of the 5G systems.