Enhancing Resiliency of Broadband Satellite Communication Emergency Networks through Propagation Impairment Mitigation Techniques

摘要

In this chapter the main issues raised from the employment of telecommunications satellites at emergency communications operating at high frequencies are described. First, the need of telecommunication systems in emergency situations is analyzed showing that these are mandatory for the disaster relief. More specifically, the chapter is focused on the presentation of the various telecommunication services which must be supported, as well as for the backhauling of these networks, by satellite systems. Since, broadband satellite communication systems operate mainly above lOGHz, the propagation impairments at these frequencies are described. They depend mainly on precipitation, atmospheric gases, clouds and tropospheric turbulence. Apart from models for the prediction of the first-order statistical characteristics, models for the generation of time series are also presented. Great attention is paid on rain attenuation, since it is the dominant fading mechanism for the satellite communication systems. Moreover, the most important propagation impairment mitigation techniques that have been proposed in the literature are presented in detail. Finally, general concepts for future research are given and some conclusions are derived.