Interference study for cognitive LTE-femtocell in TV white spaces

As one of the future indoor coverage solutions, this paper considers the cognitive Femtocell for LTE system [1], which can opportunistically access the TV white spaces. The paper selects a typical residential building for study case and uses the ray tracing method to obtain the channel profile in european TV bands. Through computer simulation, we demonstrate that cognitive LTE-Femtocell can potentially provide excellent indoor coverage. Additionally, the power leakage of every Femto-equipped building is obtained by simulation and the system performance predictions are given based on the assumptions of the Femtocell interference as shot-noise process. Two interference-avoiding antenna schemes are proposed and compared in this paper. The simulation results have shown that both schemes are very effective in managing the Femto interference, thus giving a reference for the future deployment of cognitive Femto in TV bands.