The incorporation of cognitive radio techniques in satellite communications has recently become a significant research challenge leading to the proposal of a novel network infrastructure known as cognitive satellite terrestrial networks. However, efficient resource management mechanisms should be proposed to provide a complete system analysis for this promising architecture. Towards this direction, this article focuses on the problem of power management in cognitive satellite terrestrial systems, where the satellite system has the role of the cognitive system, while the terrestrial represents the primary one. Particularly, a power control scheme for the satellite terminal is proposed. Taking into account the peculiarities of both systems and considering the uplink case, the goal of the proposed scheme is to optimise the performance of the satellite link without deteriorating the communication quality of the terrestrial link. To safeguard the communication of the terrestrial system, we introduce a novel interference-based constraint, which ensures a specific level for the inverse signal-to-interference plus noise ratio of the terrestrial link. Both the cases of perfect and imperfect channel estimation of terrestrial link are considered in order to study a more realistic scenario. Furthermore, for the imperfect case, a protection mechanism is proposed to guarantee the communication quality of the primary link that offsets the uncertainty of channel estimation. Simulation results evaluate the performance of the proposed scheme for various system parameters and verify its superiority compared with the well-known water-filling based power control scheme for both cases of perfect and imperfect channel estimation.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.