Cooperative and cognitive hybrid satellite-terrestrial networks

The development of next-generation wireless networks envisages the seamless integration between satellite systems and terrestrial cellular networks. The spectral resources allocated to satellite are not fully utilized, whereas terrestrial spectral resources are becoming overutilized day by day. Therefore, it is important to ascertain an efficient way to share the resources of space-based networks with the terrestrial networks. In view of different capabilities and services, the geostationary earth orbit (GEO) satellite could be the component of the space segment, while the terrestrial segment may be a 3G/4G heterogeneous network. With growing requirements of broadband services and limited availability of spectral resources, higher frequency bands (above 10 GHz), viz., Ku and Ka, may also need to be assigned for mobile satellite services. As such, it is quite challenging to transmit over such higher frequencies due to severe effects of atmospheric turbulence and scattering. Hence, it is imperative to explore cognitive spectrum sharing techniques to enhance spectrum utilization efficiency through the development of hybrid satellite-terrestrial communication systems. In this regard, this chapter studies the satellite-terrestrial communications with the emerging cooperative and cognitive radio techniques to promote the information and communication technology (ICT) sector in a more efficient and reliable manner. More specifically, the chapter addresses the hybrid satellite-terrestrial system design, planning, and resource allocation problems while exploiting cooperation among available network resources with hierarchical spectrum sharing to cope with the demands of futuristic wireless network.