Distributed Spectrum Access in Cognitive Radio Network Employing Rateless Codes

In this paper, we investigate a channel selection algorithm for distributed spectrum access in a multichannel multiuser cognitive radio (CR) network employing rateless codes. Each secondary user (SU) uses rateless codes to increase the tolerance of interference either from other SUs or from the primary user (PU). However, due to the unpredictable arrival of PU and the inaccuracy of spectrum sensing, the more the number of channels each SU selects, the more interference to PU will be caused. With the purpose of protecting PU from interference, we derive the optimal number of channels selected by SU to maximize the throughput of SU. Both theoretical analysis and simulation results demonstrate the efficiency of the proposed algorithm.