On the capacity of Wi-Fi System in TV white space with aggregate interference constraint

Abstract

In this paper, we present a quantitative assessment of the performance of a Wi-Fi like system in TV white space and compare it with the traditional Wi-Fi system in the ISM band. Particular emphasis is given to the constraint on the aggregate secondary interference on TV reception, which is regarded as the premise of the link throughput analysis that followed. Numerical evaluation is performed over different scenarios where the TV receive signal strength, number of unoccupied TV channels, user density are varied. Our results show that the primary interference constraint has only significant impact on the secondary system performance in rural scenario with low TV receive signal strength. In other cases, where higher transmit power does not guarantee better performance, the capacity of the system is limited by the secondary self-interference or collisions rather than the interference constraint. Therefore, efficient TV White Space utilization can be achieved by properly setting the secondary transmit power adaptive to different environments.