PROJECT TITLE :

Access Delay of Cognitive Radio Networks Based on Asynchronous Channel-Hopping Rendezvous and CSMA/CA MAC

ABSTRACT:

As a promising approach to the rendezvous downside in cognitive radio networks (CRNs), a blind rendezvous paradigm has recently spawned various asynchronous channel-hopping (CH) rendezvous schemes that enable any 2 neighboring secondary users to satisfy among multiple channels at intervals a finite time, even with no synchronization. However, the rendezvous delay that was derived in existing work is unable to replicate the particular channel access delay performance in multiuser CRNs, as it only relies on hopping patterns of the elaborately designed CH sequences (CHSs) and ignores the impact of network factors (e.g., channel availability and multiuser contention). In this paper, channel access delay is investigated by jointly considering asynchronous CH rendezvous schemes, channel availability, and a medium-access control (MAC) protocol in an exceedingly single-hop multiuser CRN. To coordinate multiuser competition, a carrier sense multiple access with collision avoidance (CSMA/CA) MAC is adopted by tailoring the IEEE 802.11 distributed coordination operate (DCF) properly to the operation options of existing asynchronous CH rendezvous schemes. The channel access delay is analyzed based mostly on a changed Bianchi model and an absorbing Markov chain model, that captures the aggregate impact of hopping patterns of CHSs, the dynamic nature of channel availability, and therefore the behavior of the MAC protocol. The analytical results are verified through in depth simulations. Each simulation and analytical results reveal that the rendezvous delay in existing asynchronous CH rendezvous schemes is insufficient to ensure satisfactory channel access delay in multiuser CRNs.