Traffic assignment algorithm for multi-path routing in Cognitive Radio Ad Hoc Networks

End-to-end delay minimization is one of key challenges in multi-hop Cognitive Radio Ad Hoc Networks (CRAHNs), where the opportunistic transmission impacts on each hop of routing paths. However, the problem is only considered in routes establishment while traffic assignment is also an important process of packet delivery in highly dynamic transmission environment. For this reason, a novel queue theory based optimal traffic assignment algorithm for multi-path routing in CRAHNs is proposed to minimize the overall end-to-end delay in this paper, which dynamically assigns the traffic load on multiple routing paths considering the spectrum availability and service rate of each hop. The algorithm is performed in using a gradient-based search method to find the optimal traffic assignment strategy. The simulation results demonstrate that the proposed algorithm significantly outperforms other baseline schemes in end-to-end delay in CRAHNs.