A database-assisted spectrum aggregation algorithm in TV White Spaces for Femtocells

In this paper, we research how to aggregate and allocate spectrum fragments of TVWS for Femto Base Stations (FBSs) in order to make full use of the nonuniform interference relationship between them. A database architecture control entity is introduced. Assisted by the entity, interference relationship between FBSs can be obtained in a cognitive manner and a distinctive graph coloring model considering spectrum aggregation is developed. We then propose the database-assisted spectrum aggregation algorithm (DSAA) which enables multiple FBSs to utilize the same spectrum fragments simultaneously in which they don´t interfere with each other. Numerical results show that the proposed algorithm outperforms the traditional algorithms in the total access bandwidth of the Femtocell system and the accessing performance of the Femtocell network.