Analytical and simulation study of the effect of secondary user cooperation on cognitive radio networks

This paper presents an analytical and simulation study of the efficiency of using cooperative communication for Dynamic Spectrum Access (DSA) in secondary infrastructure networks. The licensed and unlicensed network transmissions are modeled using a Discrete Time Markov Chain (DTMC). The secondary network spectrum occupancy and throughput are evaluated analytically and by simulation. A COoperative and COgnitive MAC protocol (CO²MAC) is developed to facilitate cooperative transmissions in secondary infrastructure networks. The results show significant performance enhancement for cooperative transmission over direct transmission, especially in crowded spectrum, where it achieves up to 80% enhancement in throughput compared to direct transmission.