Title
Energy-Efficient Joint Sensing Duration, Detection Threshold, and Power Allocation Optimization in Cognitive OFDM Systems.
Abstract
This paper investigates an energy efficiency optimization problem in cognitive orthogonal frequency division multiplexing systems. The goal is to maximize the energy efficiency by adapting the sensing duration, detection threshold, and transmit power to the constraints of the energy consumption of the secondary network and the interference to the primary network in a statistical manner. First, the case of identical detection threshold for all subcarriers is considered. In order to circumvent the intractability of the resulting problem, an alternate iteration framework is proposed to iteratively solve the three decoupled subproblems: sensing duration optimization, detection threshold optimization, and power allocation optimization. By exploiting the characteristics of each subproblem, the proposed framework is proved to be convergent. Then, the case with individual detection threshold for each subcarrier is explored. By proving that the optimal detection threshold is the root of a quadratic equation with one unknown variable, the proposed framework can be applied with minor modification. Simulation results show that the proposed alternating optimization framework can approach rapidly to the optimal solution, with less than 1% gap. Compared with the existing schemes, both the cases with identical and individual detection thresholds can achieve a considerable energy efficiency gain, with the latter further outperforming the former.
Year
DOI
Venue
2016
10.1109/TWC.2016.2613920
IEEE Trans. Wireless Communications
Keywords
Field
DocType
Sensors,OFDM,Optimization,Resource management,Interference,Energy consumption,Data communication
Subcarrier,Mathematical optimization,Transmitter power output,Efficient energy use,Interference (wave propagation),Energy consumption,Optimization problem,Mathematics,Orthogonal frequency-division multiplexing,Cognitive radio
Journal
Volume
Issue
ISSN
15
12
1536-1276
Citations 
PageRank 
References 
1
0.36
0
Authors
5
Name
Order
Citations
PageRank
Wenjun Xu14511.81
Xuemei Zhou221.39
Chia-han Lee360755.50
Zhiyong Feng414829.14
Jiaru Lin564680.74