Joint optimization of node selection and power allocation in wireless sensor networks

Energy efficiency (EE) is an important factor for the deployment of wireless sensor networks. Cooperative communication can help to reduce energy consumption for long distance data transmission. This paper mainly presents the joint optimization of node selection and power allocation for cooperative communication in wireless sensor networks. The proposed brute force approach based on optimal power allocation method can maximize EE with power constraint, and the optimal power allocation is presented as a closed-form solution by solving Lagrangian function. To reduce further complexity, the greedy node selection method is proposed. Finally, numerical results show that the proposed greedy node selection scheme can obtain the performance almost identical to the brute force approach through MATLAB simulation.