Satellite component of NGN: Integrated and hybrid networks

Future mobile networks are expected to involve systems that are based on different technologies, such as WiFi, WiMAX, 2G/3G/3G+, LTE, and satellite. To address this scenario, ITU has defined integrated and hybrid networks in the framework of Next-Generation Networks. The interest is to exploit the cooperation of different wireless communication systems (segments) to provide service to mobile users in the most efficient way, taking into account signal quality (coverage), traffic congestion conditions, and cost issues. Integrated and hybrid networks have the potential to be an efficient and cost-effective solution to employ satellite communications for mobile users. In the view of this, our paper focuses on the design of integrated/hybrid systems taking into account physical, MAC, and network layers issues. System examples and standards are described as well. Then, cooperative diversity techniques and traffic engineering issues for overflow traffic are discussed. This paper concludes identifying some possible future trends.