Cognitive Radio Routing Research Articles

Link Availability Prediction for Cognitive Radio Ad Hoc Networks

One critical issue for routing in cognitive radio ad hoc networks (CRAHNs) is how to select a reliable path for forwarding traffic. This is because mobility may cause radio links to break frequently. The reliability of a path depends on the availability of those links that constitutes the path. In this letter, we present a novel approach to predict the probability of the availability of the link between two cognitive radio nodes. The prediction is achieved by estimating the link activation and spectrum activation probabilities. Our prediction is verified by simulation and proved to be accurate. This study can provide reliability assurance on dynamic routing for cognitive radio ad hoc networks.

Distributed best-route selection for multipath routing in cognitive radio ad hoc networks

Multipath routing has great potential for improving the end-to-end performance of cognitive radio ad hoc networks (CRAHNs). Formulated multipath routing in multi-hop CRAHNs as a stochastic process optimisation problem, which allows secondary users to select routes in light of the dynamic occupancy of a licensed spectrum. Simulation results verify that the proposed multipath routing selection scheme can provide significant improvements in both the end-to-end delay and energy efficiency for secondary users.

QoS multicast routing in cognitive radio ad hoc networks

SUMMARYIn this paper, we discussed the issues of QoS multicast routing in cognitive radio ad hoc networks. The problem of our concern was: given a cognitive radio ad hoc network and a QoS multicast request, how to find a multicast tree so that the total bandwidth consumption of the multicast is minimized while the QoS requirements are met. We proposed two methods to solve it. One is a two‐phase method. In this method, we first employed a minimal spanning tree‐based algorithm to construct a multicast tree and then proposed a slot assignment algorithm to assign timeslots to the tree links such that the bandwidth consumption of the tree is minimized. The other is an integrated method that considers the multicast routing together with the slot assignment. Extensive simulations were conducted to show the performance of our proposed methods. Copyright © 2011 John Wiley & Sons, Ltd.

Cognitive Radio Routing and Optimal Spectrum Assignment Algorithm

Aiming to the shortcoming of traditional route protocols in cognitive radio networks, cognitive radio routing and optimal spectrum assignment (CRRSA) algorithm was proposed. In this paper, we consider the situation that non-interfering among the adjacent jump, and present the optimal allocation of available spectrum, and then calculate the bandwidth of end-to-end path, finally select the maximize bandwidth of end-to-end path as the best transmission route. Simulation results show that the End-to-End bandwidth of CRRSA is larger than that of traditional routing algorithm.

Cross-layer Routing Design in Cognitive Radio Networks by Colored Multigraph Model

In this paper, the cross-layer design routing in cognitive radio(CR) networks is studied. We propose a colored multigraph based model for the temporarily available spectrum bands, called spectrum holes in this paper. Based on this colored multigraph model, a polynomial time algorithm with complexity O(n 2) is also proposed to develop a routing and interface assignment, where n is the number of nodes in a CR network. Our algorithm optimizes the hop number of routing, meanwhile, the adjacent hop interference (AHI) is also optimized locally.