Interference Alignment for OFDM Cognitive Radio Networks in TV White Space Spectrum

Inhalt:
In this work, an OFDM secondary system is enabled to work in the TV white space spectrum (TVWS) based on a combination of interference alignment (IA) and a statistical protection criterion. Firstly, based on the protection criterion and IA, the maximum transmit power of the CR transmitters is determined using a centralized database. IA gives the opportunity for multiple secondary users (SUs) to access the non-used TVWS; furthermore, it simplifies the optimization problem by decoupling the interference from the unintended SUs. Afterwards, IA based resource allocation is performed on the CR system considering the maximum power that is resulted from the protection criterion in order to maximize the throughput of the CR system. The simulation is performed using a real data about TV transmitters provided by the national institute for broadcasting services in Germany, in which the performance of our proposed present better sum-rate performance compared to the compared techniques.