Research And Implementation Of Multiple-Devices Rendezvous Algorithm For Cognitive Radio AD-HOC Networks

With the explosive proliferation of wireless devices, it is becoming increasingly evident that the problem of frequency bands’ getting congested could never be settled only by fixed spectrum allocation policies. Instead, the emerging dynamic spectrum access techniques, which are expected to enable more efficient utilization of spectrum holes by opportunistically access without impacting the licensed owners, are proposed to solve these current spectrum inefficiency issues. This new area of research foresees that further improvement in spectrum efficiency will be achieved supposing great development of cognitive radio ad-hoc network and thus, to some extent, the issues of spectrum scarcity are able to be solved.In this paper, a rendezvous algorithm for multiple-devices in cognitive radio ad-hoc network is discussed in theory and implemented in practice. Our work focuses on the in-depth exploration of cognitive radio ad-hoc network architecture, which is conducted with further study on SDR (Software Defined Radio) as well as USRP/GNU Radio platforms.Through building the specific system model of rendezvous problem, theoretical analysis of probability in discovering is carried out under the condition of different users and channels. Moreover, according to the results of the analysis, the existing channel-grouping based peer-to-peer rendezvous algorithm is optimized and a new multiple-devices rendezvous strategy is proposed as well, appending to the simulation results in performance of the above two algorithms. Finally, a simple cognitive radio ad-hoc network system on USRP/GNU Radio platform has been designed and implemented. The actual test shows the performance of such system and the adopted algorithms in practice.