Throughput Performance of Interference Mitigation Techniques in Cognitive Femtocell Networks

The exponential growth in demand for higher data rates and other services in wireless networks require a more dense deployment of base stations which results in more demand of the radio spectrum. Due to the scarcity of radio spectrum and the under-utilization of assigned spectrum, government regulatory bodies have started to review their spectrum allocation policies so as to implement opportunistic spectrum access (sharing) through cognitive femtocells. The cognitive femtocell technique is however challenging due to uncertainties associated with co-tier and cross-tier interference, adjacent channel fading, path loss, and other environment dependent conditions that bring about a progressive degradation of the signal coverage. In this paper, we review the different interference solutions and prioritize the Optimal Static Fractional Frequency Re-use (OSFFR) approach. We analyze the system performance with different metrics such as throughput, number of free channels and Bit Error Rate. Simulation results show that the proposed OSFFR shows an improved result compared to other frequency reuse schemes.