Research on Spectrum Hole Distribution for Cognitive Radio Systems

In this paper, we at first studied the distribution of the interval between two consecutive packets (ITCP) for two-user networks. We then extend our interest to multi-user networks by using fitting curves to approximate the distribution of the ITCP. Next, based on the above observation, we present a new spectrum hole prediction model for the IEEE 802.11 standards based cognitive radio (CR) local areas networks. The effectiveness of the presented prediction model was thereafter validated by using NS-2 and MATLAB simulation programs. Simulation results showed that when adopting the proposed spectrum hole prediction model, CR systems can largely reduce the number of collisions with licensed users.