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Space-Time Correlation Based Fast Regional Spectrum Sensing in cognitive radio

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China Communications 2017年第5期14卷 78-90页

作者： Sai Huang Yuanyuan Yao Zhiyong Feng Ping Zhang Yifan Zhang Key Laboratory of Universal Wireless Communications Ministry of Education Wireless Technology Innovation Institute(WTI) Beijing University of Posts and TelecommunicationsBeijing 100876China

In this paper,a space-time correlation based fast regional spectrum sensing(RSS)scheme is proposed to reduce the time and energy consumption of traditional spatial spectrum sensing. The target region is divided into small meshes,and all meshes are clustered into highly related groups using the spatial correlation among them. In each group,some representative meshes are selected as detecting meshes(DMs)using a multi-center mesh(MCM)clustering algorithm,while other meshes(EMs)are estimated according to their correlations with DMs and the Markov modeled dependence on history by MAP principle. Thus,detecting fewer meshes saves the sensing consumption. Since two independent estimation processes may provide contradictory results,minimum entropy principle is adopted to merge the results. Tested with data acquired by radio environment mapping measurement conducted in the downtown Beijing,our scheme is capable to reduce the consumption of traditional sensing method with acceptable sensing performance.

关键词： cognitive radio Channel occupancy estimation Dynamic spectrum access radio environment mapping Space-time correlation Spectrum sensing

A Novel Spectrum Handoff-Based Sensing-Throughput Tradeoff Scheme in cognitive radio

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China Communications 2016年第12期13卷 59-68页

作者： Xin Liu Feng Li Weidang Lu School of Information and Communication Engineering Dalian University of Technology College of Information Engneering Zhejiang University of Technology

In cognitive radio(CR), there is a tradeoff between spectrum sensing time and throughput of secondary user(SU). In the conventional sensing-throughput tradeoff scheme, when the presence of the primary user(PU) is detected, the SU will stop forwarding data and wait to redetect the PU in the following frame, yielding great throughput loss. In order to improve the SU's throughput, a novel sensing-throughput tradeoff scheme is proposed, which allows the SU to search for a new idle channel through spectrum searching and transfer to this channel to continue communication, when the presence of the PU is detected. An optimization problem is proposed to maximize the SU's throughput in the proposed scheme through jointly optimizing the sensing time, the searching time and the number of available channels, providing that the detection probability to the PU is guaranteed. By fixing the number of channels, based on alternating direction optimization, the joint optimization algorithm of sensing time and searching time is proposed, and then the optimal number of channels is obtained through enumerative searching. The simulation results show that there exist the optimal solutions to the proposed scheme, and the proposed scheme outperforms the conventional scheme notably, with different detection probabilities and sampling frequencies.

关键词： cognitive radio energy sensing throughput sampling frequency detection probability

Quorum-based channel hopping scheme for cognitive radio networks

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Science China(Information Sciences) 2013年第4期56卷 219-224页

作者： LI XiaoYan ZHANG HaiLin HU Fei SHI Chao State Key Laboratory of Integrated Services Networks Xidian University Department of Electrical and Computer Engineering University of Alabama

In cognitive radio networks,secondary users(SUs) tune themselves to the available spectrum to meet each other and establish communication links to transmit *** is the rendezvous *** hopping(CH) schemes have been proposed to establish pairwise *** this paper,we present a distributed CH scheme based on the quorum system to make SUs rendezvous on their common available channels within a bounded *** scheme can guarantee rendezvous even when SUs sense different sets of available *** results show that the proposed CH scheme outperforms existing schemes in terms of average time-to-rendezvous and success rate.

关键词： cognitive radio channel hopping scheme rendezvous quorum system MAC

Cooperative spectrum sensing in cognitive radio systems with limited sensing ability

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Journal of Zhejiang University-Science C(Computers and Electronics) 2010年第3期11卷 175-186页

作者： Hui HUANG Zhao-yang ZHANG Peng CHENG Ai-ping HUANG Pei-liang QIU Department o fin formation Science and Electronic Engineering Zhejiang University Hangzhou 310027 China Intel China Research Center Intel Lab Beijing 100191 China

In cognitive radio systems,the design of spectrum sensing has to face the challenges of radio sensitivity and wide-band frequency agility. It is difficult for a single cognitive user to achieve timely and accurate wide-band spectrum sensing because of hardware limitations. However,cooperation among cognitive users may provide a way to do so. In this paper,we consider such a cooperative wide-band spectrum sensing problem with each of the cognitive users able to imperfectly sense only a small portion of spectrum at a time. The goal is to maximize the average throughput of the cognitive network,given the primary network's collision probability thresholds in each spectrum sub-band. The solution answers the essential questions:to what extent should each cognitive user cooperate with others and which part of the spectrum should the user choose to sense? An exhaustive search is used to find the optimal solution and a heuristic cooperative sensing algorithm is proposed to simplify the computational com-plexity. Inspired by this optimization problem,two practical cooperative sensing strategies are then presented for the centralized and distributed cognitive network respectively. Simulation results are given to demonstrate the promising performance of our proposed algorithm and strategies.

关键词： cognitive radio Cooperative spectrum sensing Limited sensing ability Throughput

Multi-channel power allocation based on market competitive equilibrium in cognitive radio networks

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Science China(Information Sciences) 2014年第2期57卷 68-79页

作者： LU YanHui MEI YaNan WANG Wei MU XiaoMin YANG ShouYi School of Information Engineering Zhengzhou University

cognitive radios such as intelligent phones and Bluetooth devices have been considered essential goods in next-generation communication *** devices will have to share the same frequency band owing to the limited bandwidth *** improve spectrum efciency,we formulate multi-channel power allocation as a market competitive equilibrium(CE)problem,and prove that its solution exists and is unique under the condition of weak *** then propose two distributed power allocation algorithms achieving CE,namely the fast convergent power allocation algorithm(FCPAA)and the social-fairness-aware FCPAA(SFAF).Theoretical analysis and simulation results demonstrate that the proposed algorithms lead to better system performance in terms of the guaranteed interference temperature constraint using the price mechanism instead of a strategy based on the Nash ***,it is shown that the FCPAA maximizes total utility,and converges more quickly than the method addressed in prior research with the help of improved round-robin ***,the FCPAA cannot ensure the same social fairness among secondary users as the SFAF scheme in both the non-fading channel and Rayleigh fading channel;the SFAF balances the individual utility by adjusting each user’s budget at the expense of a small quantity of system total throughput.

关键词： cognitive radio rate allocation power allocation market competitive equilibrium Nash equilibrium

Statistical QoS Guarantees for Energy Harvesting cognitive radio Networks

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Journal of Communications and Information Networks 2020年第1期5卷 100-110页

作者： Yuquan Xiao Wenchi Cheng State Key Laboratory of Integrated Services Networks Xidian UniversityXi’an 710071China

Spectrum and energy resources are very important for the rapidly developing of thefifth generation(5G)wireless communication *** radio and energy harvesting technologies,which focus on the spectrum efficiency and the energy efficiency,respectively,can be jointly used for solving the scarcities of spectrum and energy in energy harvesting cognitive radio networks(EHCRNs),where the energy is absorbed from ambient space and spectrum is licensed to the primary ***,how to guarantee the quality of service(QoS)for EHCRNs is still a challenging *** this paper,we develop the optimal power and rate adaptation scheme under statistical QoS provisioning for *** particular,we analyze the power constraints of ***,we formulate the effective capacity maximization problem for EHCRNs,solving which we obtain the closedform of the optimal power allocation and rate adaptation scheme under different power *** analyses verify the effective capacity enhancement and validate the relationships among the effective capacity,the QoS exponent,the energy arrival rate,and the average interference power.

关键词： cognitive radio energy harvesting effective capacity quality of service power allocation

Effective capacity of delay quality-of-service constrained spectrum sharing cognitive radio with outdated channel feedback

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Science China(Information Sciences) 2013年第6期56卷 115-127页

作者： XU Ding FENG ZhiYong ZHANG Ping Key Laboratory of Universal Wireless Communications Ministry of EducationBeijing University of Posts and Telecommunications

In this paper,we consider a spectrum sharing cognitive radio network coexisting with a primary ***,the channel state information(CSI) between the secondary transmitter and the primary receiver is assumed to be outdated due to channel feedback *** secondary user(SU) is assumed to satisfy a given delay quality-of-service(QoS) constraint as well as the average interference power *** aim to derive the maximum arrival rate of the SU under aforementioned constraints with the outdated *** this respect,we derive the optimal power allocation to achieve the maximum effective capacity,and further derive the effective *** closed-form expressions for the lower and upper bounds on the effective capacity are also *** addition,we obtain the effective capacities under two widely adopted adaptive transmission schemes,i.e.,optimal power and rate allocation(OPRA) and truncated channel inversion with fixed rate(TIFR).Numerical results are conducted to corroborate our *** is shown that the effective capacities of the SU under various transmission schemes are insensitive to the channel correlation coefficient especially under low channel correlation *** is also shown that the lower and upper bounds on the effective capacity are significantly tight under stringent delay QoS constraint.

关键词： cognitive radio effective capacity outdated channel feedback delay QoS constraint interferencepower constraint

Power Control Algorithm of cognitive radio Based on Non-Cooperative Game Theory

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China Communications 2013年第11期10卷 143-154页

作者：赵军辉杨涛贡毅王娇付雷 School of Electronics and Information Engineering Beijing Jiaotong University State Key Laboratory of Rail Traffic Control and Safety Beijing Jiaotong University Key Laboratory of Wireless Sensor Network and Communication Shanghai Institute of Microsystem and Information TechnologyChinese Academy of Sciences Department of Electrical and Electronic Engineering South University of Science and Technology of China

This paper addresses the power con- trol problems of cognitive radio （CR） trader transmission power and interference tempera- ture constraints. First, we propose the interfer- ence constraint which ensures that the Quality of Service （QoS） standards for primary users is considered and a non-cooperative game power control model. Based on the proposed model, we developed a logical utility function based on the Signal-to-Interference-Noise Ratio （S/NR） and a novel algorithm network power control. that is suitable for CR Then, the existence and uniqueness of the Nash Equilibrium （NE） in our utility function are proved by the principle of game theory and the corresponding optimi- zations. Compared to traditional algorithms, the proposed one could converge to an NE in 3-5 iterative operations by setting an appropriate pricing factor. Finally, simulation results ver- ified the stability and superiority of the novel algorithm in flat-fading channel environments.

关键词： cognitive radio non-cooperativepower control game theory utility function Na-sh equilibrium target power

Cooperative spectrum sensing based on stochastic resonance in cognitive radio networks

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Science China(Information Sciences) 2014年第2期57卷 58-67页

作者： LIN YingPei HE Chen JIANG LingGe HE Di Department of Electronic Engineering Shanghai Jiao Tong University

A new censoring cooperative spectrum sensing scheme based on stochastic resonance(SR)technique in cognitive radio(CR)network is proposed in this *** observations of the cooperative secondary users(SUs)whose statistics fall into the censoring interval are processed by SR system in the proposed *** hard fusion and the soft fusion for the censoring cooperative spectrum sensing scheme are analyzed *** analyses and simulation results show that the proposed censoring cooperative spectrum sensing scheme has the same detection performance as and lower computational complexity than the method that each cooperative SU performs spectrum sensing using SR-based energy detection,and its detection performance is superior to that of the conventional method that all the cooperative SUs perform spectrum sensing using energy detection in hard *** soft fusion,the proposed censoring cooperative spectrum sensing based on equal gain combination can achieve the optimal sensing performance approximately.

关键词： cognitive radio cooperative spectrum sensing stochastic resonance information fusion