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cognitive radio adaptation for power consumption minimization using biogeography-based optimization

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Chinese Physics B 2016年第12期25卷 499-506页

作者：齐佩汉郑仕链杨小牛赵知劲 School of Telecommunications Engineering Xidian University Xi'an 710071 China Science and Technology on Communication Information Security Control Laboratory Jiaxing 314033 China School of Telecommunications Hangzhou Dianzi University Hangzhou 310018 China

Adaptation is one of the key capabilities of cognitive radio, which focuses on how to adjust the radio parameters to optimize the system performance based on the knowledge of the radio environment and its capability and characteristics. In this paper, we consider the cognitive radio adaptation problem for power consumption minimization. The problem is formulated as a constrained power consumption minimization problem, and the biogeography-based optimization （BBO） is introduced to solve this optimization problem. A novel habitat suitability index （HSI） evaluation mechanism is proposed, in which both the power consumption minimization objective and the quality of services （QoS） constraints are taken into account. The results show that under different QoS requirement settings corresponding to different types of services, the algorithm can minimize power consumption while still maintaining the QoS requirements. Comparison with particle swarm optimization （PSO） and cat swarm optimization （CSO） reveals that BBO works better, especially at the early stage of the search, which means that the BBO is a better choice for real-time applications.

关键词： cognitive radio power consumption adaptation optimization

Intelligent reflecting surface-assisted cognitive radio-inspired rate-splitting multiple access systems

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Digital Communications and Networks 2023年第3期9卷 655-666页

作者： Peixu Liu Gang Jing Hongwu Liu Liang Yang Theodoros A.Tsiftsis School of Information Science and Electrical Engineering Shandong Jiaotong UniversityJinan250357China School of Transportation and Logistics Engineering Shandong Jiaotong UniversityJinan250357China College of Computer Science and Electronic Engineering Hunan UniversityChangsha410082China School of Intelligent Systems Science and Engineering Jinan UniversityZhuhai519070China

Intelligent reflecting surface(IRS)has been widely regarded as a promising technology for configuring wireless propagation *** this paper,we utilize IRS to assist transmission of a secondary user(SU)in a cognitive radio-inspired rate-splitting multiple access(CR-RSMA)system in which a primary user's(PU's)quality of service(QoS)requirements must be *** introducing intolerable interference to deteriorate the PU's outage performance,the SU conducts rate-splitting to transmit its signal to the base-station through the direct link and IRS reflecting *** the IRS-assisted CR-RSMA(IRS-CR-RSMA)scheme,we derive the optimal transmit power allocation,target rate allocation,and successive interference cancellation decoding order to enhance the outage performance of the *** closed-form expression for the SU's outage probability achieved by the IRS-CR-RSMA scheme is *** simulation results are presented to clarify the enhanced outage performance achieved by the proposed IRS-CR-RSMA scheme over the CR-RSMA scheme.

关键词： Rate-splitting multiple access(RSMA) Intelligent reflecting surface(IRS) Successive interference cancellation(SIC) cognitive radio

Improved spectrum sharing algorithm based on feedback control information in cognitive radio networks

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Journal of Systems Engineering and Electronics 2013年第4期24卷 564-570页

作者： Yibing Li Rui Yang Fang Ye Zhenguo Gao College of Information and Communication Engineering Harbin Engineering University College of Automation Harbin Engineering University

In order to avoid the system performance deterioration caused by the wireless fading channel and imperfect channel estimation in cognitive radio networks, the spectrum sharing problem with the consideration of feedback control information from the primary user is analyzed. An improved spectrum sharing algorithm based on the combination of the feedback control information and the optimization algorithm is proposed. The relaxation method is used to achieve the approximate spectrum sharing model, and the spectrum sharing strategy that satisfies the individual outage probability constraints can be obtained iteratively with the observed outage probability. Simulation results show that the proposed spectrum sharing algorithm can achieve the spectrum sharing strategy that satisfies the outage probability constraints and reduce the average outage probability without causing maximum transmission rate reduction of the secondary user.

关键词： cognitive radio spectrum sharing power control feedback control information.

A novel weighed cooperative bandwidth spectrum sensing for spectrum occupancy of cognitive radio network

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Journal of Central South University 2016年第7期23卷 1709-1718页

作者：刘鑫陈琨奇闫钧华 School of Information and Communication Engineering Dalian University of Technology College of Astronautics Nanjing University of Aeronautics and Astronautics

In cognitive radio network(CRN), a secondary user(SU) may utilize the spectrum resource of the primary user(PU) and avoid causing harmful interference to the primary network(PN) via spectrum sensing. In the traditional time spectrum sensing, the SU cannot detect the PU's presence during its transmission, thus increasing interference to the PN. In this work, a novel weighed cooperative bandwidth spectrum sensing method is proposed, which allows multiple SUs to use part of the bandwidth to perform cooperative spectrum sensing throughout the whole frame in order to detect the PU's reappearance in time. The SU's spectrum efficiency is maximized by jointly optimizing sensing bandwidth proportion, number of cooperative SUs and detection probability, subject to the constraints on the SU's interference and the false alarm probability. Simulation results show significant decrease on the interference and improvement on the spectrum efficiency using the proposed weighed cooperative bandwidth spectrum sensing method.

关键词： cognitive radio spectrum sensing spectrum efficiency interference

Q-Learning Based Interference-Aware Channel Handoff for Partially Observable cognitive radio Ad Hoc Networks

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Chinese Journal of Electronics 2017年第4期26卷 856-863页

作者： XU Ning ZHANG Huyin XU Fang WANG Zhiyong Department of Computer Wuhan University

Channel handoff is a crucial function for cognitive radio ad hoc networks(CRAHNs). The absence of centralized infrastructures and the limited power make the handoff design more challenging. A learningbased interference-aware handoff scheme is proposed for distributed CRAHNs. We model the channel handoff process as a Partially observable Markov decision process(POMDP) and adopt a Q-learning algorithm to find an optimal handoff strategy in a long term. The proposed algorithm obtains an efficient transmission performance by considering the interferences among SUs and PUs. To achieve PU awareness, the handoff scheme predicts the PU activities by using the historical channel usage statistics. In addition, we also propose a refined channel selection rule to compromise between learning speed and cumulative transmission reward. The simulation results show that the proposed handoff scheme can adapt to the PU activities and achieves a better performance in terms of high throughput and low collisions. And the learning process keeps a considerable balance between convergence time and cumulative reward.

关键词： cognitive radio Ad hoc networks Partially observable Markov decision process(POMDP) Handoff Q-Learning

Joint power and spectrum allocation algorithm in cognitive radio networks

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Journal of Systems Engineering and Electronics 2011年第4期22卷 691-701页

作者： Anna Auguste Anghuwo Communication Research Center Harbin Institute of Technology

The spectrum sharing problem between primary and cognitive users is mainly investigated. Since the interference for primary users and the total power for cognitive users are constrained, based on the well-known water-filling theorem, a novel one-user water-filling algorithm is proposed, and then the corresponding simulation results are given to analyze the feasibility and validity. After that this algorithm is used to solve the communication utility optimization problem subject to the power constraints in cognitive radio network. First, through the gain to noise ratio for cognitive users, a subcarrier and power allocation algorithm based on the optimal frequency partition is proposed for two cognitive users. Then the spectrum sharing algorithm is extended to multiuser conditions such that the greedy and parallel algorithms are proposed for spectrum sharing. Theory and simulation analysis show that the subcarrier and power allocation algorithms can not only protect the primary users but also effectively solve the spectrum and power allocation problem for cognitive users.

关键词： cognitive radio spectrum sharing water-filling algo-rithm interference constraint communication overhead.

Effective capacity region and power allocation for two-way spectrum sharing cognitive radio networks

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Science China(Information Sciences) 2015年第6期58卷 126-135页

作者： XU Ding LI Qun Wireless Communication Key Lab of Jiangsu Province Nanjing University of Posts and Telecommunications School of Computer Science and Technology Nanjing University of Posts and Telecommunications

In this paper, we consider a spectrum sharing cognitive radio(CR) network where a pair of twoway secondary users(SUs) is allowed to coexist with a primary user(PU) as long as the interference power received at the PU is below an acceptable limit. Under the interference power constraint, we investigate the effective capacity region for two-way SUs. In particular, we derive a closed-form solution for the power allocation problem to achieve the boundary points of an inner bound on the effective capacity region. We also propose a key parameter referred to as weighted-transmission-interference-ratio(WTIR), which plays a significant role in the power allocation policy. In the proposed power allocation policy, the exclusive transmission of SUs shall be performed if one SU’s WTIR is much larger than the others. That is, the one with much larger WTIR shall be allocated non-zero power and the other one shall be allocated zero power. Otherwise, if the difference of their WTIRs is not significant, the concurrent transmission shall be performed. That is, both SUs shall be allocated non-zero power. It is shown that a loose interference power constraint leads to the concurrent transmission in most situations, while a stringent interference power constraint leads to the exclusive transmission in most situations. It is also shown that for the stringent interference power constraint and loose delay quality-of-service(Qo S) constraint, the proposed power allocation policy is almost optimal and thus the obtained inner bound on the effective capacity region is tight.

关键词： cognitive radio effective capacity delay quality-of-service power allocation two-way

Time-Efficient Power Allocation Scheme for Two-Way Multi-relay cognitive radio Networks

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Chinese Journal of Electronics 2016年第2期25卷 357-363页

作者： ZHOU Zhikang ZHU Qi The Key Wireless Lab of Jiangsu Province School of Telecommunication and Information EngineeringNanjing University of Posts and Telecommunications Key Lab on Wideband Wireless Communications and Sensor Network Technology of Ministry of Education

Cooperative relaying has been emerging as a key technology in cognitive radio(CR) networks. A two-way Amplify-and-forward(AF) based multi-relay CR network is considered, where a primary user coexists with a pair of secondary users and multiple relays. A Timeefficient sub-optimal power allocation scheme(TESOPA)based on Cauchy-Schwarz inequality is provided to maximize the total end-to-end transmission rate of the secondary system. TESOPA is proposed under maximal transmission power constraints, while ensuring the quality of service of the primary user during the whole communication process. The computational complexity is sharply decreased by using the Cauchy-Schwarz inequality. Simulation results show that the proposed TESOPA scheme performs very close to the near-optimal Interior point method based power allocation(IPMPA), especially in interference dominant networks where interference constraints play a key role in determining power allocation results instead of maximal transmission power constraints.

关键词： Power allocation Relay network cognitive radio Amplify-and-forward Two-way communication

Optimal Price-Based Power Control Algorithm with Quality of Service Constraints in cognitive radio Networks

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Chinese Journal of Electronics 2015年第2期24卷 393-397页

作者： WANG Zhengqiang JIANG Lingge HE Chen Department of Electronic Engineering Shanghai Jiaotong University Department of Communication and Information Engineering Chongqing University of Posts and Telecommunications

In price-based cognitive radio networks,the Primary user(PU) can allow the Secondary users(SUs) to access by pricing if their interference power is under the Interference power constraint(IPC). The interaction between the PU and the SUs is modeled as a Stackelberg game with the consideration of the Quality of service(Qo S) of the SUs. The revenue maximization problem of PU is expressed as an equivalent convex optimization problem if the minimum Signal-to-interference and noise ratio(SINR) constraints for the SUs are greater than or equal to 0d B. An optimal pricing algorithm is proposed based on this equivalent convex optimization problem. Simulation results show that the proposed pricing algorithm outperforms the non-uniform pricing algorithm in terms of the revenue of the PU, the sum rate of SUs and the number of admitted SUs.

关键词： Power control cognitive radio Price Quality of service(QoS)