Abstract
An optimal power allocation (OPA) policy for orthogonal frequency division multiplexing (OFDM)-based cognitive radio networks (CRNs) using underlay spectrum access model is presented under multiple secondary users (SUs) with energy harvesting (EH). The proposed algorithm can allocate transmission power to each SU on each subcarrier with the objective of maximizing the average throughput of secondary network over a finite time interval. We consider both the interference power constraint limited by primary user (PU) and the minimum throughput constraint of each SU to improve the throughput of SUs while guaranteeing the communication quality of PU. To balance current throughput and expected future throughput, a dynamic programming (DP) problem is defined and solved by the backward induction method. Moreover, for each time slot, a convex immediate optimization is presented to obtain an optimal solution, which can be solved by the Lagrange dual method. Simulation results show that our policy can achieve better performance than some traditional policies and ensure good quality of service (QoS) of PU when SUs access the spectrum.
Highlights
Cognitive radio (CR) [1] is an optional solution to solve the spectrum shortage problem, which can both improve efficiency of spectrum utilization and ensure quality of service (QoS)
The optimal power allocation (OPA) for energy harvesting (EH) cognitive radio networks (CRNs) is studied in [8], the authors consider the problem of system throughput maximization over a finite horizon rather than at a certain time slot, and they adopt a rate loss constraint to protect the transmission of primary user (PU)
We focus on the maximization of the average throughput of the secondary system within K time slots under the maximum transmission power constraint, the minimum throughput constraint of secondary users (SUs), and the interference power constraint defined by PU
Summary
Cognitive radio (CR) [1] is an optional solution to solve the spectrum shortage problem, which can both improve efficiency of spectrum utilization and ensure quality of service (QoS). The OPA for EH CRN is studied in [8], the authors consider the problem of system throughput maximization over a finite horizon rather than at a certain time slot, and they adopt a rate loss constraint to protect the transmission of primary user (PU). A novel saving-sensing transmitting (SST) frame structure for EH CRNs is proposed in [11], where the authors aim to maximize the energy utilization efficiency of SU by jointly optimizing the save ratio and transmission power under both the energy causality constraint and the minimum throughput constraint. A POMDP is proposed in [13] to trade off energy consumption and throughput gain in hybrid CRN, where SU dynamically determines its operation mode for each time slot ( e.g., to be idle or to transmit), sensing time, and access mode. Based on the above discussions, we propose an OPA policy for the EH CRN considering multiusers with the underlay spectrum access model. We select the underlay spectrum access model in which SU has the opportunity to coexist with PU, while SU must control the interference to PU under a certain threshold
Sign-in/Register to view highlights & summary Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callMore From: EURASIP Journal on Wireless Communications and Networking
Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
