Joint Resource Allocation and Route Selection for Multi-hop Cognitive Relay Networks

Abstract

In this paper, a multi-hop cognitive relay network consisting of multiple PU transmission pairs, SU transmission pairs and relay SUs is considered. To achieve the performance enhancement of multi-hop transmission links between SU pairs, an energy efficient constrained shortest path first (CSPF)based joint resource allocation and route selection algorithm is proposed, which consists of two sub-algorithms, i.e., CSPFbased route selection sub-algorithm and energy efficiencybased resource allocation sub-algorithm. More specifically, we first apply CSPF-based route selection sub-algorithm to obtain the shortest transmission route under the transmission constraints. Then, an energy efficiency-based resource allocation problem of the shortest routes is formulated and solved by applying iterative algorithm and Lagrange dual method. Finally, the energy efficiency of the shortest transmission routes is examined and the globally optimal route selection and resource allocation strategy is obtained which offers the maximal energy efficiency of the transmission route. Simulation results demonstrate the effectiveness of the proposed algorithm.