title: Energy-efficient cognitive radio sensor networks: parametric and convex transformations.
abstract: Designing energy-efficient cognitive radio sensor networks is important to intelligently use battery energy and to maximize the sensor network life. In this paper, the problem of determining the power allocation that maximizes the energy-efficiency of cognitive radio-based wireless sensor networks is formed as a constrained optimization problem, where the objective function is the ratio of network throughput and the network power. The proposed constrained optimization problem belongs to a class of nonlinear fractional programming problems. Charnes-Cooper Transformation is used to transform the nonlinear fractional problem into an equivalent concave optimization problem. The structure of the power allocation policy for the transformed concave problem is found to be of a water-filling type. The problem is also transformed into a parametric form for which a ε-optimal iterative solution exists. The convergence of the iterative algorithms is proven, and numerical solutions are presented. The iterative solutions are compared with the optimal solution obtained from the transformed concave problem, and the effects of different system parameters (interference threshold level, the number of primary users and secondary sensor nodes) on the performance of the proposed algorithms are investigated.
authors: ELCE Department, Ryerson University, Toronto, ON, Canada. muhammadnaeem@gmail.com
authors: Muhammad
authors: M
authors: Naeem
authors: Kandasamy
authors: K
authors: Illanko
authors: Ashok
authors: A
authors: Karmokar
authors: Alagan
authors: A
authors: Anpalagan
authors: Muhammad
authors: M
authors: Jaseemuddin
mesh_terms: D000465:Algorithms; D003195:Computer Communication Networks / Q000295:instrumentation*; D017076:Computer-Aided Design; D011211:Electric Power Supplies; D004735:Energy Transfer; D004867:Equipment Design; D019544:Equipment Failure Analysis; D013685:Telecommunications / Q000295:instrumentation*; D014159:Transducers