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A New Signature Scheme with Shared Verification

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The Journal of China Universities of Posts and Telecommunications 2006年第2期13卷 66-69页

作者： JIA Xiao-yun LUO Shou-shan yuan chao-wei School of Continuing Education Beijing University of Posts and Telecommunications Beijing 100876 P.R. China School of Software Engineering Beijing University of Posts and Telecommunications Beijing 100876 P.R. China National Key Laboratory of Integrated Service Networks Xidian University Xi'an 710071 P.R. China

With expanding user demands, digital signature techniques are also being expanded greatly, from single signature and single verification techniques to techniques supporting multi-users. This paper presents a new digital signature scheme with shared verification based on the fiat-shamir signature scheme. This scheme is suitable not only for digital signatures of one public key, but also for situations where multiple public keys are required. In addition, the scheme can resist all kinds of collusion, making it more practicable and safer. Additionally it is more efficient than other schemes.

关键词： digital signature shared verification verifiable secret sharing

Analysis of secondary throughput and optimization in cooperative spectrum sensing

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The Journal of China Universities of Posts and Telecommunications 2011年第4期18卷 39-44页

作者： LI Mei-ling yuan chao-wei LI Lin YANG Rui-zhe School of Information and Communication Engineering Beijing University of Posts and Telecommunications Beijing 100876 China School of Electronics and Information Engineering Taiyuan University of Science and Technology Taiyuan 030024 China College of Electronic Information and Control Engineering Beijing University of Technology Beijing 100022 China

In cooperative spectrum sensing, more secondary user makes more opportunity for detecting the vacant spectrums, which resulting the spectrum utilization improved, however much bandwidth would be occupied for sending the local observation results, inducing the reduced secondary throughput. In this paper, an adaptive algorithm for selecting detection threshold was proposed, where the maximized secondary throughput can always be achieved while assuring sufficient protection to primary user, regardless of the number of sensing users in cognitive radio networks. Theoretical analysis and simulation results validate the proposed scheme.

关键词： cooperative spectrum sensing secondary throughput spectrum utilization primary user secondary user detection threshold

Feedback threshold with guaranteed QoS in multiuser OFDM systems

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The Journal of China Universities of Posts and Telecommunications 2009年第2期16卷 24-28页

作者： YANG Rui-zhe yuan chao-wei TENG Ying-lei ZHANG Yan-hua School of Information and Telecommunication Engineering Beijing University of Posts and Telecommunications Beijing 100876 China School of Electronic Information and Control Engineering Beijing University of Technology Beijing 100124 China

A threshold setting scheme is proposed based on the resource management and limited feedback theory in multiuser orthogonal frequency division multiplexing （OFDM） systems. In adaptive resource allocation, the factors denoting the quality of service （QoS） and fairness are both considered as the user weight. From the aspect of feedback outage probability, the proposed algorithm sets the threshold for each user related to its weight, which brings enough feedback to the user with greater weight. Analysis and simulation results show that, compared with the threshold ignoring weights, the proposed scheme has much lower feedback load while with better QoS.

关键词： OFDM multiuser multimedia traffic limited feedback

Novel limited feedback scheme under the MIMO broadcast system

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The Journal of China Universities of Posts and Telecommunications 2009年第6期16卷 11-16页

作者： CHENG Tie-zheng,yuan chao-wei School of Information and Communication Engineering,Beijing University of Posts and Telecommunications,Beijing 100876,China School of Information and Communication Engineering Beijing University of Posts and Telecommunications Beijing 100876 China

By deducing the distribution of the normalized channel covariance matrix,a novel limited feedback scheme is proposed under multiple users（MU） multiple-input multiple-output（MIMO） broadcast channel（BC） *** proposed scheme has advantages in three ***,it has no constraints on the number of users or ***,each user＇s feedback bits are independent of the number of receiving ***,the proposed scheme avoids the storage of large-size codebook on the *** results show that the performance of the proposed scheme is close to the perfect channel state information（CSI） case and it just needs a small number of feedback bits.

关键词： MIMO broadcast channel limited feedback normalized channel covariance

Cross-talk between calcium and reactive oxygen species signaling

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Acta Pharmacologica Sinica 2006年第7期27卷 821-826页

作者： yuan YAN chao-liang wei Wan-rui ZHANG He-ping CHENG Jie LIU~1 Laboratory of Calcium Signaling,Institute of Molecular Medicine,Peking University,Beijing 100871,China Laboratory of Calcium Signaling Institute of Molecular Medicine Peking University Beijing China

Calcium(Ca2+)and reactive oxygen species(ROS)constitute the most importantintracellular signaling molecules participating in the regulation and integration ofdiverse cellular *** we briefly review cross-talk between the two promi-nent signaling systems that finely tune the homeostasis and integrate functional-ity of Ca2+and ROS in different types of ***2+modulates ROS homeostasisby regulating ROS generation and annihilation mechanisms in both the mitochon-dria and the *** redox regulation of Ca2+homeostasis occurs indifferent physiological and pathological processes,by modulating componentsof the Ca2+signaling toolkit and altering characteristics of local and global Ca2+***,interactions between Ca2+and ROS signaling systems canbe both stimulatory and inhibitory,depending on the type of target proteins,theROS species,the dose,duration of exposure,and the cell *** extensiveand complex cross-talk might enhance signaling coordination and integration,whereas abnormalities in either system might propagate into the other system andundermine the stability of both systems.

关键词： calcium reactive oxygen species signal transduction receptor cross talk

非同分布高斯信号背景下基于增强能量检测的协作感知

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北京邮电大学学报 2018年第6期41卷 39-44页

作者：黄河袁超伟北京邮电大学信息与通信工程学院北京100876

能量检测算法应用于无线通信场景中时存在信噪比(SNR)墙和噪声不确定性问题,对此,在认知无线电非同分布高斯信号背景下,提出了基于增强能量检测的协作感知算法.在低SNR条件下,给出了采用增强能量检测算法的次用户检测概率和虚警概率,并... 详细信息

能量检测算法应用于无线通信场景中时存在信噪比(SNR)墙和噪声不确定性问题,对此,在认知无线电非同分布高斯信号背景下,提出了基于增强能量检测的协作感知算法.在低SNR条件下,给出了采用增强能量检测算法的次用户检测概率和虚警概率,并推导出达到最小总错误率的最优协作用户数表达式.理论分析和仿真实验结果表明,相对其他克服噪声不确定性的能量检测算法,所提出的算法具有更优的检测性能.

关键词：认知无线电协作感知噪声不确定性

一种组合时频分布在跳频信号参数估计中的应用

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西安电子科技大学学报 2010年第6期37卷 1137-1142页

作者：冯涛袁超伟北京邮电大学信息与通信工程学院北京100876 中国电科集团第54研究所河北石家庄050081

为了有效分析跳频信号并估计其参数,根据跳频信号的特点,提出了一种基于频率分解的组合时频分布.这种新的时频分布先将多分量跳频信号通过带通滤波变成多个单分量信号,再将每个分量的Wigner-Ville分布线性叠加.理论分析和仿真结果表明,... 详细信息

为了有效分析跳频信号并估计其参数,根据跳频信号的特点,提出了一种基于频率分解的组合时频分布.这种新的时频分布先将多分量跳频信号通过带通滤波变成多个单分量信号,再将每个分量的Wigner-Ville分布线性叠加.理论分析和仿真结果表明,这种新的组合时频分布能够有效抑制跳频信号的交叉项干扰.与现有的方法相比,具有更高的时频分辨率,更适合于跳频信号的时频分析和参数估计.

关键词：跳频信号组合时频分布交叉项时频分辨率