Efficient NC-OFDM-Based Control Channel Establishment in Cognitive Radio Networks
Chin-Jung Liu, Pei Wen Huang, Li Xiao · 2016
In cognitive radio (CR) networks, control channels are needed for secondary users (SUs) to perform certain handshaking procedures to negotiate communication parameters and to exchange control messages. The process of SUs attempting to meet on a channel is known as rendezvous. Previous studies either use a dedicated control channel or adopt channel-hopping schemes to rendezvous. However, it is not realistic to designate a preselected control channel in licensed spectrum bands and the time consumption for channel hopping grows drastically. Moreover, a requirement of previous studies is that a common channel must be available across the whole network at all SUs. Such a channel might not exist and the SUs cannot form an effective CR network. This paper proposes an efficient approach for guaranteed NC-OFDM-based Control Channel (NCCC) establishment by utilizing subcarrier pulses. Simulation results show that the time needed for establishing control channel is lower than that of channel hopping schemes. Additionally, the proposed approach is able to establish NCCC even if there is no common channel in the CR network. NC-OFDM-based control interfaces improve the control channel establishment rate even when the interface can only access the spectrum bandwidth that is equal to one channel.