A Resource Reservation Scheme in Cognitive Radio Ad Hoc Networks for C4I Systems

Command, control, communication, computer and intelligence (C4I) systems provide situational awareness, which contributes to the decision making process in complex operational environment. The C4I systems need real time seamless information exchange amongst its elements over a distributed network. Cognitive radio (CR) is an emerging wireless technology that can use spectrum in an entirely new and more efficient manner and offer efficient, secure, and reliable communications. In CR ad hoc networks, spectrum efficiency and energy efficiency are vitally important because spectrum availability is opportunistic in nature and mobile CR nodes usually have limited energy. Aiming to improve network throughput along with improving spectrum and energy efficiencies, this paper proposes a resource reservation scheme for C4I systems, called channel-slot aggregation diversity based slot reservation (CADSR), by which each CR node can utilize multiple slots in different channels simultaneously and efficiently utilize the power control mechanism. The proposed scheme dynamically assigns channel-slots to CR nodes using the diversity technique. A dynamic frame length expansion and shrinking scheme has also been introduced that improves the slot utilization. Simulation results show that the proposed CADSR mechanism achieves significant performance improvement as compared to the state-of-the-art approaches.