Efficient resource scheduling for a secondary network in shared spectrum

With limited opportunities to open up new unencumbered bands to mobile wireless services, interest in enhancing methods for sharing of spectrum between services is high. For example, the band 1695-1710 MHz is expected to be made available to 3GPP Long-Term Evolution cellular network uplinks by sharing with incumbent meteorological satellite services already in the band. The LTE networks are to be operated in a manner that ensures no loss of incumbent capability by adhering to protection requirements such as a limit on the aggregate interference power at fixed incumbent earth station locations. In this paper, we consider this specific spectrum sharing scenario as motivation and formulate an optimization framework for power control and time-frequency resource scheduling on the LTE uplink with an aggregate interference constraint. We design and propose a novel algorithm inspired by numerical solution and analysis of the optimization problem. Using theory and simulation, we show that our algorithm significantly outperforms more simplistic approaches, well approximates the optimal solution, and is of sufficient scope and complexity for practical implementation, even in relatively large LTE networks. Algorithms of this kind are necessary for mobile wireless networks to make the most of constrained spectrum resources in shared bands.