Estimation of Channel Availability in Cognitive Radio Networks

Cognitive Radio Networks (CRNs) improve spectrum usage by opportunistically sharing licensed spectrum with cognitive capable devices when the licensed users are idle. However, the constraint in such opportunistic communication is that the cognitive users need to evacuate the channel as and when the licensed user becomes active. Consequently, it leads to sudden termination of ongoing sessions of cognitive devices which in turn yields undesirable communication overhead and degraded service quality. So, channel availability estimation is an important aspect of the acceptability of CRN routing protocols. In this paper, we have performed an analysis of channel estimation in CRN in a scenario of mobile licensed as well as cognitive users. First, some mathematical propositions and theorems are stated for determining the availability of a channel, possibility of successful communication, and suitability of the channel to select cognitive users at specific instant in time. The stated propositions are subsequently proved in support of the channel estimation. Second, the mathematical analysis is with ns-3 simulation. Both mathematical and simulated observations are in line and reveal the benefits of adopting the proposed strategy in cognitive radio networks.