NCCC: NC-OFDM-based control channel establishment in cognitive radio networks using subcarrier pulses

In cognitive radio networks (CRN), the secondary users need control channels for negotiating communication parameters and exchanging control messages. Previous studies either preselect a dedicated control channel or find a control channel dynamically using channel-hopping (CH) approaches. However, preselected control channels in the licensed spectrum are unrealistic, and the time it takes for CH-based approaches increases drastically when the number of channels increases. NC-OFDM is a promising technology that can access partial channels and aggregate spectrum fragments. However, forming NC-OFDM-based Control Channel (NCCC) is seldom discussed. Therefore, we propose an efficient approach for guaranteed NCCC establishment by utilizing subcarrier pulses. The results show that the time needed for NCCC is lower than that of CH-based approaches. Additionally, the proposed approach can establish NCCC even if there is no common channel in the CRN. NC-OFDM-based control interfaces improve the control channel establishment rate even if the interfaces can only access the spectrum bandwidth that is equal to one channel.