Robust Relay Selection and Power Allocation for OFDM-Based Cooperative Cognitive Radio Networks

In this paper, we study the robust relay selection and power allocation problems for orthogonal frequency division multiplexing (OFDM) based cooperative cognitive radio networks (CRNs) with channel uncertainties. The objective is to maximize the capacity of the cooperative CRN, which is subject to the interference threshold constraints of primary users (PUs) and the total transmit power limitation of secondary user (SU) and relays. We describe all possible channel uncertainties with ellipsoid set and interval set. The robust relay selection and power allocation problems are formulated as semi-infinite programming (SIP) problems, respectively. We convert the SIP problems into their equivalent convex optimization problems with the worst-case approach, which can be solved by the Lagrange dual decomposition method. Simulation results show that the proposed robust relay selection and power allocation algorithm can strictly guarantee the quality of service of PUs under channel uncertainties.

[1]  Ying-Chang Liang,et al.  Optimal Power Allocation Strategies for Fading Cognitive Radio Channels with Primary User Outage Constraint , 2011, IEEE Journal on Selected Areas in Communications.

[2]  Lu Lv,et al.  Energy efficient relay selection and power allocation for cooperative cognitive radio networks , 2015, IET Commun..

[3]  Mengyao Ge,et al.  Efficient Resource Allocation for Cognitive Radio Networks with Cooperative Relays , 2013, IEEE Journal on Selected Areas in Communications.

[4]  Geoffrey Ye Li,et al.  Cognitive radio networking and communications: an overview , 2011, IEEE Transactions on Vehicular Technology.

[5]  Georgios B. Giannakis,et al.  Chance-Constrained Optimization of OFDMA Cognitive Radio Uplinks , 2013, IEEE Transactions on Wireless Communications.

[6]  Faouzi Bader,et al.  Asymptotically Optimal Resource Allocation in OFDM-Based Cognitive Networks with Multiple Relays , 2012, IEEE Transactions on Wireless Communications.

[7]  Sidan Du,et al.  Power allocation for orthogonal frequency division multiplexing-based cognitive radio networks with cooperative relays , 2014, IET Commun..

[8]  Arkadi Nemirovski,et al.  Selected topics in robust convex optimization , 2007, Math. Program..

[9]  Saeedeh Parsaeefard,et al.  Robust Worst-Case Interference Control in Underlay Cognitive Radio Networks , 2012, IEEE Transactions on Vehicular Technology.

[10]  Rajendra Bhatia,et al.  A CAUCHY-SCHWARZ INEQUALITY FOR OPERATORS WITH APPLICATIONS , 1995 .

[11]  Alagan Anpalagan,et al.  Resource Allocation Techniques in Cooperative Cognitive Radio Networks , 2014, IEEE Communications Surveys & Tutorials.

[12]  Vijay K. Bhargava,et al.  Relay and Power Allocation Schemes for OFDM-Based Cognitive Radio Systems , 2011, IEEE Transactions on Wireless Communications.

[13]  Min Sheng,et al.  Robust Energy Efficiency Maximization in Cognitive Radio Networks: The Worst-Case Optimization Approach , 2015, IEEE Transactions on Communications.

[14]  Xiaodong Wang,et al.  Distributed Robust Optimization for Communication Networks , 2008, IEEE INFOCOM 2008 - The 27th Conference on Computer Communications.

[15]  Vijay K. Bhargava,et al.  Robust Resource Optimization for Cooperative Cognitive Radio Networks with Imperfect CSI , 2015, IEEE Transactions on Wireless Communications.

[16]  Geoffrey Ye Li,et al.  Power and Channel Allocation for Cooperative Relay in Cognitive Radio Networks , 2011, IEEE Journal of Selected Topics in Signal Processing.