Outage Minimized Joint Power and Channel Allocation in Multihop Cognitive Radio Networks: A Lifetime-Centric Approach

This paper looks for an optimal solution to address joint power and channel allocation problem in a multihop cognitive radio network (CRN). The overall goal is to minimize the end-to-end outage probability of the CRN while meeting simultaneously total transmission power and interference constraints to primary user (PU). Two different forms of interference model, with and without considering spectral distance between PU and secondary user (SU) channels, are considered where the former again uses uniform and triangular probability density functions for determining interference to PU. The problem has been solved using standard technique of solving convex optimization problem (for power allocation) and weighted bipartite matching (for channel allocation). Furthermore, the proposed solution assumes that transmitting nodes are energy constrained. Hence, network lifetime improvement is an additional design challenge. Simulation results show that the proposed scheme not only minimizes outage probability better compared to existing power allocation strategies but also results in savings of SUs power consumption, which helps to extend network lifetime significantly.