Quantifying the Effect of Path Stability on Multi-Path Routing in Cognitive Radio Ad Hoc Networks: A Markov Predictor Perspective

Mobility generally may lead to the continual loss of data and link interruptions during the communications between secondary users (SUs) in distributed underlay cognitive radio ad hoc networks (CRANETs), which raises important concerns about the stability for routing design and maintenance. In this paper, we investigate the effect of path stability on multi-path routing in distributed underlay CRANET scenario. We firstly model the stability factor of the initial state of each path as the product of the stability coupling factor of the sorted link on this path. Then, we obtain the predicted stability of each path by using the risk level of link based on a second-order Markov predictor by taking into account the relative movement direction of SUs in the proposed Markov model. Particularly, we characterize the overall stability of each path on the basis of the predicted stability of this considered path. Moreover, an effective algorithm is presented to calculate the route stability of the path with the help of the Markov predictor. We also investigate the selection problem of the optimal path through the proposed optimal path selection algorithm. Numerical results are presented to demonstrate the effectiveness and practicality of our proposed algorithm, which achieves the evaluation of the overall stability for multi-path routing.