Hybrid satellite-terrestrial broadband backhaul links: Capacity enhancement through spatial multiplexing

Broadband Satellite Communication links have been proposed as an effective solution for backhaul links in access networks. Moreover, the ever increasing demand for high data rates has led to the use of frequencies above 10GHz. At these frequency bands, rain attenuation is the dominant fading mechanism and the only atmospheric phenomenon exhibiting significant spatial inhomogeneity. The cooperation of hybrid satellite-terrestrial systems and the Multiple-Input Multiple-Output (MIMO) techniques have been proposed in order to support high throughput and overcome the fading effects. In this work, the performance of a hybrid satellite-terrestrial MIMO system is studied and the outage capacity is analytically calculated. The antenna gains are adjusted to the different path losses of the satellite and terrestrial links resulting in a balanced MIMO system in terms of the Equivalent Isotropically Radiated Power (EIRP). Extended numerical results illustrate the performance gain of the spatial multiplexing techniques compared to a single satellite (SISO) system.