A multi-stage resource-constrained spectrum access mechanism for cognitive radio IoT networks: Time-spectrum block utilization

Abstract

Extravagant demands for wireless communications have resulted in the shortage of spectrum, such that unlicensed spectrum bands are overcrowded, whereas licensed bands are not utilized efficiently. Moreover, content discovery and retrieval using the traditional host-centric approach of IP-based networks adds more burden on the wireless spectrum, such that, each time a request is initiated by the mobile service requester, a new routing path is discovered to retrieve the service from the service provider. Cognitive radio (CR) technology has been proposed to enable efficient and opportunistic spectrum band usage through the utilization of vacant licensed channels. This can offer huge spectrum to enable efficient large-scale deployment for IoT networks. Moreover, Information Centric Networking (ICN) has been proposed to decouple the service requester from the provider such that in-network content caching is used to allow for the retrieval of services within a mobile node’s proximity. The integration of CR and ICN will be essential for enabling envisioned IoT services within smart cities. In this article, we consider the multi-user single-transceiver coordinated spectrum access problem in CR-IoT networks under the overlay spectrum sharing model. We formulate the spectrum access problem as a multi-stage rate/channel assignment optimization problem. The objective is to maximize the overall network throughput by maximizing the achieved sum-rate over all contending CR-IoT devices. Specifically, we propose a novel resource-constrained channel assignment policy that provides a proper utilization of the available time–frequency units. The proposed policy also exploits the packet fragmentation capability to further enhance network throughput. Moreover, we envision a scenario where our proposed solution can be adapted to information-centric cognitive radio-based networking for IoT smart city applications. We showcase the significant improvement achieved by our proposed solution over state-of-the-art schemes through simulation results.