Gateway diversity scheme for a future broadband satellite system

Future internet demands are being increased dramatically year by year. Terrestrial systems are unable to satisfy these demands in all geographical areas and thus broadband access by satellite is a key service provision platform. Considering the traffic demands, the raw capacity should approach a Terabit/s by 2020 to meet these demands. So the challenge is to reduce the cost/bit and to increase the satellite capacity from today´s 10 Gbps to 1 Tbps by 2020. In order to find the available spectrum, the migration to higher bands such as Ka-band, Q/V bands is considered a neccessity. But migrating to these higher bands in order to have access to more available spectrum, we experience severe precipitation attenuation, and the feeder links that carry much more capacity are more vulnerable to these high attenuations. ACM is unable to cope with the precipitation fades in these higher bands, and single site diversity results in an excessive number of extra earth stations which is not cost effective. It is envisaged that future systems may interconnect gateways to allow traffic routing between them, a so called `Smart Gateway diversity scheme´. This scheme is discussed and potential architectures are proposed. We evaluate the performance of such schemes in terms of their availability.