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Pattern Matrix Design of PDMA for 5G UL Applications 被引量:4
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作者 Bin Ren Yingmin Wang +2 位作者 Xiaoming Dai Kai Niu Wanwei Tang 《China Communications》 SCIE CSCD 2016年第S2期159-173,共15页
Pattern division multiple access(PDMA),which is a novel non-orthogonal multiple access(NOMA),has been proposed to address the challenges of massive connectivity and higher spectral efficiency for fifth generation(5G) ... Pattern division multiple access(PDMA),which is a novel non-orthogonal multiple access(NOMA),has been proposed to address the challenges of massive connectivity and higher spectral efficiency for fifth generation(5G) mobile network.The performance of PDMA mainly depends on the design of PDMA pattern matrix.In this paper,pattern matrix design of PDMA for 5G uplink(UL) applications in massive machine type communication(mMTC) and enhanced mobile broadband(eMBB) deployment scenarios are studied.The design criteria and examples for application in UL mMTC and UL eMBB are investigated.The performance of the PDMA pattern matrix is analyzed with the discrete constellation constrained capacity(CC-Capacity),and verified by Monte Carlo simulation.The simulation results show that the preferred PDMA pattern matrix can achieve good performance with different overloading factors(OF). 展开更多
关键词 5G non-orthogonal multiple access PDMa pattern matrix CC-Capacity SIC
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Wavelet Numerical Solutions for Weakly Singular Fredholm Integral Equations of the Second Kind 被引量:1
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作者 TANG Xinjian PANG Zhicheng +1 位作者 ZHU Tonglin LIU Jian 《Wuhan University Journal of Natural Sciences》 CAS 2007年第3期437-441,共5页
Daubechies interval cally weakly singular Fredholm kind. Utilizing the orthogonality equation is reduced into a linear wavelet is used to solve nurneriintegral equations of the second of the wavelet basis, the integra... Daubechies interval cally weakly singular Fredholm kind. Utilizing the orthogonality equation is reduced into a linear wavelet is used to solve nurneriintegral equations of the second of the wavelet basis, the integral system of equations. The vanishing moments of the wavelet make the wavelet coefficient matrices sparse, while the continuity of the derivative functions of basis overcomes naturally the singular problem of the integral solution. The uniform convergence of the approximate solution by the wavelet method is proved and the error bound is given. Finally, numerical example is presented to show the application of the wavelet method. 展开更多
关键词 weakly singular integral equations interval wavelet sparse matrix
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RIS辅助MIMO NOMA系统中利用统计CSI的下行传输方法
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作者 陆佳程 王斌 +1 位作者 张军 倪艺洋 《电子与信息学报》 EI CAS CSCD 北大核心 2024年第4期1257-1265,共9页
针对可重构智能反射表面(RIS)辅助多输入多输出(MIMO)非正交多址接入(NOMA)下行传输系统,该文提出利用统计信道状态信息(CSI)的基站发送协方差矩阵与RIS相移矩阵设计方法。首先,在莱斯空间相关信道假设下,利用大维随机矩阵理论,推导了RI... 针对可重构智能反射表面(RIS)辅助多输入多输出(MIMO)非正交多址接入(NOMA)下行传输系统,该文提出利用统计信道状态信息(CSI)的基站发送协方差矩阵与RIS相移矩阵设计方法。首先,在莱斯空间相关信道假设下,利用大维随机矩阵理论,推导了RIS辅助MIMO NOMA系统遍历和速率的确定性表达式;然后,在弱用户速率约束与发送功率受限的条件下,通过最大化确定性大系统近似和速率,利用统计CSI,分别设计了强、弱用户的次优发送协方差矩阵和RIS的相移矩阵。仿真结果表明,所推导的近似表达式具有很好的近似效果,所设计的发送协方差矩阵和相移矩阵能显著提升系统的和速率。 展开更多
关键词 统计信道状态信息 非正交多址接入 可重构智能反射表面 发送协方差 大维随机矩阵理论
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Infinite Matrix Rings on Spaces with Signed-Weakly Gliding Hump Property
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作者 曲文波 刘金霞 《Northeastern Mathematical Journal》 CSCD 2000年第4期454-458,共5页
In this paper, several elementary properties of infinite matrix rings on spaces with the singed weakly gliding hump property are obtained.
关键词 Infinite matrix ring singed weakly glidiing hump property
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Optimizing Memory Access Efficiency in CUDA Kernel via Data Layout Technique
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作者 Neda Seifi Abdullah Al-Mamun 《Journal of Computer and Communications》 2024年第5期124-139,共16页
Over the past decade, Graphics Processing Units (GPUs) have revolutionized high-performance computing, playing pivotal roles in advancing fields like IoT, autonomous vehicles, and exascale computing. Despite these adv... Over the past decade, Graphics Processing Units (GPUs) have revolutionized high-performance computing, playing pivotal roles in advancing fields like IoT, autonomous vehicles, and exascale computing. Despite these advancements, efficiently programming GPUs remains a daunting challenge, often relying on trial-and-error optimization methods. This paper introduces an optimization technique for CUDA programs through a novel Data Layout strategy, aimed at restructuring memory data arrangement to significantly enhance data access locality. Focusing on the dynamic programming algorithm for chained matrix multiplication—a critical operation across various domains including artificial intelligence (AI), high-performance computing (HPC), and the Internet of Things (IoT)—this technique facilitates more localized access. We specifically illustrate the importance of efficient matrix multiplication in these areas, underscoring the technique’s broader applicability and its potential to address some of the most pressing computational challenges in GPU-accelerated applications. Our findings reveal a remarkable reduction in memory consumption and a substantial 50% decrease in execution time for CUDA programs utilizing this technique, thereby setting a new benchmark for optimization in GPU computing. 展开更多
关键词 Data Layout Optimization CUDa Performance Optimization GPU Memory Optimization Dynamic Programming matrix Multiplication Memory access Pattern Optimization in CUDa
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A method based on vector type for sparse storage and quick access to projection matrix
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作者 杨娟 侯慧玲 石浪 《Journal of Measurement Science and Instrumentation》 CAS CSCD 2015年第1期53-56,共4页
For sparse storage and quick access to projection matrix based on vector type, this paper proposes a method to solve the problems of the repetitive computation of projection coefficient, the large space occupation and... For sparse storage and quick access to projection matrix based on vector type, this paper proposes a method to solve the problems of the repetitive computation of projection coefficient, the large space occupation and low retrieval efficiency of projection matrix in iterative reconstruction algorithms, which calculates only once the projection coefficient and stores the data sparsely in binary format based on the variable size of library vector type. In the iterative reconstruction process, these binary files are accessed iteratively and the vector type is used to quickly obtain projection coefficients of each ray. The results of the experiments show that the method reduces the memory space occupation of the projection matrix and the computation of projection coefficient in iterative process, and accelerates the reconstruction speed. 展开更多
关键词 projection matrix sparse storage quick access vector type
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Large System Analysis of Downlink C-RAN with Phase Noise and Fronthaul Compression 被引量:2
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作者 Yishi Xue Jun Zhang +2 位作者 Shi Jin Gan Zheng Hongbo Zhu 《China Communications》 SCIE CSCD 2019年第8期58-71,共14页
This paper studies the effect of phase noise and fronthaul compression on a downlink cloud radio access network(C-RAN), where several remote radio heads(RRHs) are coordinated to communicate with users by a baseband un... This paper studies the effect of phase noise and fronthaul compression on a downlink cloud radio access network(C-RAN), where several remote radio heads(RRHs) are coordinated to communicate with users by a baseband unit(BBU) on the cloud server. In the system, the baseband signals are precoded at BBU, and then compressed before being transmitted to RRHs through capacity-limited fronthaul links which results in the compressive quantization noise. We assume the regularized zero-forcing precoding is performed with an imperfect channel state information and a compression strategy is applied at BBU. The effect of phase noise arising from nonideal local oscillators both at RRHs and users is considered. We propose an approximate expression for the downlink ergodic sum-rate of considered C-RAN utilizing large dimensional random matrix theory in the large-system regime. From simulation results, the accuracy of the approximate expression is validated, and the effect of phase noise and fronthaul compression can be analyzed theoretically based on the approximate expression. 展开更多
关键词 cloud radio access network phase noise capacity-limited fronthaul LINKS large DIMENSIONaL random matrix theory
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PAPR reduction in mobile WiMAX:A new ZCMT precoded random interleaved OFDMA system 被引量:1
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作者 I.Baig V.Jeoti 《Journal of Central South University》 SCIE EI CAS 2012年第4期988-993,共6页
Mobile WiMAX(worldwide interoperability for microwave access) air interface adopts orthogonal frequency division multiple access(OFDMA) as multiple access technique for its uplink(UL) and downlink(DL) to improve the m... Mobile WiMAX(worldwide interoperability for microwave access) air interface adopts orthogonal frequency division multiple access(OFDMA) as multiple access technique for its uplink(UL) and downlink(DL) to improve the multipath performance.All OFDMA based networks,like mobile WiMAX,experience the problem of high peak-to-average power ratio(PAPR).The high PAPR increases the complexity of analog-to-digital(A/D) and digital-to-analog(D/A) convertors,and also reduces the efficiency of RF high-power-amplifier(HPA).In this work,a new zadoff-chu matrix transform(ZCMT) precoding based random interleaved orthogonal frequency division multiple access(OFDMA) system was proposed for PAPR reduction in mobile WiMAX system.The system is based on precoding the constellation symbols with the ZCMT precoder before subcarrier mapping.The PAPR of proposed system is analyzed with the root-raised-cosine(RRC) pulse shaping to keep out of band radiation low and meet the transmission spectrum mask requirement.Simulation results show that the proposed system has better PAPR gain than the hadamard transform(WHT) precoded random interleaved OFDMA systems and the conventional random interleaved OFDMA systems.Symbol-error-rate(SER) performance of the system is also better than the conventional random interleaved OFDMA systems and the random interleaved OFDMA systems with WHT.The good improvement in PAPR significantly reduces the cost and the complexity of the transmitter. 展开更多
关键词 peak to average power ratio orthogonal frequency division multiple access zadoff-chu matrix transform mobileWiMaX root-raised-cosine pulse shaping
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Performance Analysis of Multiple User Optical Code Division Multiple Access
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作者 Himanshu Monga R. S. Kaler 《Optics and Photonics Journal》 2014年第2期21-25,共5页
In this paper, we discuss and analyze an optical code division multiple access for multiple user system. Media access control implementation has been considered. For fulfilling the huge need of bandwidth services, tec... In this paper, we discuss and analyze an optical code division multiple access for multiple user system. Media access control implementation has been considered. For fulfilling the huge need of bandwidth services, technology tends to move to optical networks and three major optical systems come into existence. Code division of the optical network is most used and real concept interacted with users up to this time. Optical code division multiple access provides complete spectrum to each and every user for the time of accessing the channel. In the paper, we have proposed network architecture with optical encoder and decoder along with optical code translator which is supporting multiple user systems. We integrate the code translator with encoding and decoding of optical code to use the optical network at full extent and present the simulation validation results of 6 Gb/s 3-hop transmission by use of proposed architecture. Further, we have implemented experimentation with 6 users 3 Gb/s optical code division multiple access network. Through simulation structure, it is shown that the combination of encoding with EDFA in multiple user environment system provides improvement in bit error rate and also improves the multiple access interference. With increase of users in the network, MAI value increases and our proposed scheme controls interference in the network. 展开更多
关键词 OPTICaL Code DIVISION MULTIPLE aCCESS Strong INTERFERENCE Weak INTERFERENCE Bit Error Rate OPTICaL Encoding Laser DIODE Source MULTIPLE aCCESS INTERFERENCE
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Existence of Multiple Positive Periodic Solutions for Second Order Differential Equations
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作者 Lü Yue Sun Peng +1 位作者 Cai Hua Han Pei-shan 《Communications in Mathematical Research》 CSCD 2016年第3期272-280,共9页
Let α be a nonzero endomorphism of a ring R, n be a positive integer and T_n(R, α) be the skew triangular matrix ring. We show that some properties related to nilpotent elements of R are inherited by T_n(R, α).... Let α be a nonzero endomorphism of a ring R, n be a positive integer and T_n(R, α) be the skew triangular matrix ring. We show that some properties related to nilpotent elements of R are inherited by T_n(R, α). Meanwhile, we determine the strongly prime radical, generalized prime radical and Behrens radical of the ring R[x; α]/(x^n), where R[x; α] is the skew polynomial ring. 展开更多
关键词 skew triangular matrix ring skew polynomial ring weak zip property strongly prime radical generalized prime radical
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WCX-MB联合MALDI-TOF MS技术建立宫颈癌诊断预测模型及初步验证 被引量:2
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作者 孙克娜 许小雨 +2 位作者 朱小双 宋御繁 刘晓斐 《生物技术通讯》 CAS 2020年第5期547-553,共7页
目的:筛选宫颈癌患者血清差异性蛋白/多肽,建立宫颈癌诊断预测模型,寻找宫颈癌潜在肿瘤标志物。方法:收集宫颈癌患者血清标本34例、良性对照组血清标本27例、健康组血清标本26例,按照3∶1随机分为训练组(宫颈癌患者25例、良性对照19例... 目的:筛选宫颈癌患者血清差异性蛋白/多肽,建立宫颈癌诊断预测模型,寻找宫颈癌潜在肿瘤标志物。方法:收集宫颈癌患者血清标本34例、良性对照组血清标本27例、健康组血清标本26例,按照3∶1随机分为训练组(宫颈癌患者25例、良性对照19例、健康者19例)和验证组(宫颈癌患者9例、良性对照8例、健康者7例)。弱阳离子交换磁珠(WCX-MB)富集低丰度蛋白/多肽,基质辅助激光解吸电离飞行时间质谱(MALDI-TOF MS)检测得到血清蛋白表达图谱,采用ClinPro Tools 3.0软件筛选差异表达蛋白/多肽峰,建立宫颈癌诊断预测模型并进行验证。结果:筛选出12个具有显著性差异的多肽峰,与健康组相比,9个差异峰在宫颈癌患者中表达上调,3个表达下调。其中多肽峰m/z 4210.90和4645.11的ROC曲线下面积分别为0.97、0.85。采用快速分类算法(QC)建立的宫颈癌诊断预测模型效能最佳,其对癌症组和健康组的诊断准确性为93.75%,特异性为100%,敏感性为88.89%;对癌症组和良性对照组的诊断准确性为88.24%,特异性为75%,敏感性为100%。结论:应用QC建立的宫颈癌诊断预测模型具有较高的诊断效能,可较好地应用于宫颈癌辅助诊断,多肽峰m/z 4210.90和4645.11有望成为诊断宫颈癌的潜在肿瘤标志物。 展开更多
关键词 弱阳离子交换磁珠 基质辅助激光解吸电离飞行时间质谱 宫颈癌 诊断预测模型
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Estimation of Decision Alternatives on the Basis of Interval Pairwise Comparison Matrices
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作者 Nataliya D. Pankratova Nadezhda I. Nedashkovskaya 《Intelligent Control and Automation》 2016年第2期39-54,共16页
This paper deals with the calculation of a vector of reliable weights of decision alternatives on the basis of interval pairwise comparison judgments of experts. These weights are used to construct the ranking of deci... This paper deals with the calculation of a vector of reliable weights of decision alternatives on the basis of interval pairwise comparison judgments of experts. These weights are used to construct the ranking of decision alternatives and to solve selection problems, problems of ratings construction, resources allocation problems, scenarios evaluation problems, and other decision making problems. A comparative analysis of several popular models, which calculate interval weights on the basis of interval pairwise comparison matrices (IPCMs), was performed. The features of these models when they are applied to IPCMs with different inconsistency levels were identified. An algorithm is proposed which contains the stages for analyzing and increasing the IPCM inconsistency, calculating normalized interval weights, and calculating the ranking of decision alternatives on the basis of the resulting interval weights. It was found that the property of weak order preservation usually allowed identifying order-related intransitive expert pairwise comparison judgments. The correction of these elements leads to the removal of contradictions in resulting weights and increases the accuracy and reliability of results. 展开更多
关键词 Interval Pairwise Comparison matrix Interval Weights weakly Consistent Interval Expert Judgments Intransitive Interval Expert Judgments Consistency Increasing of Interval Expert Judgments Weak and Strong Order Preservation
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An Improved Pairing-Free Ciphertext Policy Framework for IoT
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作者 M.Amirthavalli S.Chithra R.Yugha 《Computer Systems Science & Engineering》 SCIE EI 2023年第6期3079-3095,共17页
Internet of Things(IoT)enables devices to get connected to the internet.Once they are connected,they behave as smart devices thereby releasing sensitive data periodically.There is a necessity to preserve the confident... Internet of Things(IoT)enables devices to get connected to the internet.Once they are connected,they behave as smart devices thereby releasing sensitive data periodically.There is a necessity to preserve the confidentiality and integrity of this data during transmission in public communication channels and also permitting only legitimate users to access their data A key challenge of smart networks is to establish a secure end-to-end data communication architecture by addressing the security vulnerabilities of data users and smart devices.The objective of this research work is to create a framework encompassing Ciphertext policy Attribute-based Encryption scheme using block encryption and BLAKE hashing technique.An improved Pairing-Free-Ciphertext policy Attribute-based encryption algorithm has been developed to overcome the aforementioned challenges.Further,a comparative study has been performed between the proposed scheme and the different encryption algorithms.It is found that the proposed scheme scores well over the already existing schemes.The scheme is evaluated in terms of execution time and communication overhead.The robustness of the proposed scheme is also analyzed from the perspective of several security goals. 展开更多
关键词 Internet of things access control cipher policy based-attribute based encryption(CP-aBE) access matrix performance analysis
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SoC芯片上AHB总线矩阵的设计及验证
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作者 朱峰 刘威 《信息技术》 2023年第3期1-5,12,共6页
随着SoC的复杂度不断提高,通过集成IP核的设计方式能够加快芯片设计的周期,同时由于总线上主从设备的增加,有必要基于AHB总线设计一款高速互连的AHB总线矩阵,在AHB multi layer的基础上,将仲裁模块改为由内部寄存模块接收信息后,再由从... 随着SoC的复杂度不断提高,通过集成IP核的设计方式能够加快芯片设计的周期,同时由于总线上主从设备的增加,有必要基于AHB总线设计一款高速互连的AHB总线矩阵,在AHB multi layer的基础上,将仲裁模块改为由内部寄存模块接收信息后,再由从机端完成对各个主机发送过来的信号信息进行仲裁。同时还加入了防死锁模块,从而实现了能够根据预设的计数阈值判断AHB是否发生死锁的功能;最后通过AHB总线接口的验证IP搭建UVM仿真测试环境,对所设计的总线系统基本功能进行了测试,实现了单master访问多个slave和多个master对多个slave并行访问的功能。 展开更多
关键词 aHB总线矩阵 交叉互联 片上系统 并行访问 UVM
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关于拟正则Armendariz环
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作者 宋雪梅 《金陵科技学院学报》 2023年第1期88-92,共5页
引入拟正则Armendariz环并研究其性质。证明弱Armendariz环是拟正则Armendariz环,直积∏i∈I R i是拟正则Armendariz环当且仅当每个环R i(i∈I)是拟正则Armendariz环,同时证明R是拟正则Armendariz环当且仅当上三角矩阵环T n(R)(n≥2)是... 引入拟正则Armendariz环并研究其性质。证明弱Armendariz环是拟正则Armendariz环,直积∏i∈I R i是拟正则Armendariz环当且仅当每个环R i(i∈I)是拟正则Armendariz环,同时证明R是拟正则Armendariz环当且仅当上三角矩阵环T n(R)(n≥2)是拟正则Armendariz环,并通过例子说明任意环R上的全矩阵环M n(R)(n≥2)不是拟正则Armendariz环。 展开更多
关键词 拟正则元 aRMENDaRIZ环 拟正则armendariz环 半交换环 直积 上三角矩阵环
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不相关多子集零相关区序列集的构造
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作者 崔莉 许成谦 《系统工程与电子技术》 EI CSCD 北大核心 2024年第10期3577-3585,共9页
在多小区环境下的准同步码分多址(quasi-synchronous code-division multiple-access,QS-CDMA)系统中,不相关多子集零相关区(zero correlation zone,ZCZ)序列集不仅可以消除一定时延内来自相同小区的信号干扰,而且可以完全消除来自相邻... 在多小区环境下的准同步码分多址(quasi-synchronous code-division multiple-access,QS-CDMA)系统中,不相关多子集零相关区(zero correlation zone,ZCZ)序列集不仅可以消除一定时延内来自相同小区的信号干扰,而且可以完全消除来自相邻小区的信号干扰。针对如何基于仿酉矩阵构造多子集ZCZ序列集的问题,设计了两种构造方法。具体地,通过构造具有一定特性的多个初始矩阵,再结合仿酉矩阵,进而利用不同的初始矩阵产生不同的ZCZ序列集,且序列集间互不相关。所提方法的核心是多个初始矩阵的设计,方法1通过对离散傅里叶变换(discrete Fourier transform,DFT)矩阵进行分块与叠加实现,方法2利用已有的不相关多子集ZCZ序列集实现。由两种方法得到的构造结果,其参数趋近于最优,为解决多小区环境下的干扰抑制问题提供了新的序列设计方法。 展开更多
关键词 准同步码分多址系统 零相关区 多子集零相关区序列集 仿酉矩阵
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广义Nekrasov矩阵的判定 被引量:20
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作者 郭爱丽 刘建州 《工程数学学报》 CSCD 北大核心 2009年第4期697-702,共6页
本文对一般任意给定的矩阵,仅从矩阵的元素出发,利用定义构造特殊的正对角矩阵,结合不等式的放缩技巧,给出广义Nekrasov矩阵的一个充分判定,并用数值例子说明了所得结果的有效性。
关键词 广义NEKRaSOV矩阵 NEKRaSOV矩阵 弱Nekrasov矩阵
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一种基于组合子阵协方差矩阵的阵列扩展方法
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作者 梁国龙 罗钧戈 +1 位作者 郝宇 付进 《兵工学报》 EI CAS CSCD 北大核心 2024年第5期1717-1724,共8页
针对阵列在低信噪比条件下信号检测概率低且方位估计性能下降的问题,提出一种基于组合子阵协方差矩阵的线列阵扩展方法。该方法将阵列划分为奇偶子阵,根据子阵的互协方差与自协方差矩阵构建扩展接收数据,对扩展接收数据进行组合作为最... 针对阵列在低信噪比条件下信号检测概率低且方位估计性能下降的问题,提出一种基于组合子阵协方差矩阵的线列阵扩展方法。该方法将阵列划分为奇偶子阵,根据子阵的互协方差与自协方差矩阵构建扩展接收数据,对扩展接收数据进行组合作为最终的阵列接收数据进行处理,由此在突破阵列物理孔径的基础上避免仅使用奇偶阵元互协方差重构接收数据时产生的栅瓣问题。仿真结果表明:新方法可以降低波束输出的旁瓣,具有较好的弱目标检测能力和方位分辨力;相比于基于奇偶阵元互协方差的阵列扩展方法,新方法可有效提升方位估计精度,且不存在栅瓣问题。 展开更多
关键词 阵列扩展 弱目标检测 波达方向估计 栅瓣 协方差矩阵
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Nekrasov矩阵的推广 被引量:1
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作者 刘玉 马衍波 +1 位作者 刘建州 张超权 《西北师范大学学报(自然科学版)》 CAS 北大核心 2012年第3期18-23,共6页
推广了Nekrasov矩阵的定义,得到了几类新的矩阵,即k层Nekrasov矩阵,k层弱Nekrasov矩阵,广义k层Nekrasov矩阵;利用矩阵的性质和不等式估计,给出了这几类矩阵与广义严格对角占优矩阵之间的关系.
关键词 NEKRaSOV矩阵 k层Nekrasov矩阵 k层弱Nekrasov矩阵 广义k层Nekrasov矩阵 广义严格对角占优阵
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预条件(I+S_α)的AOR和2PPJ迭代收敛性定理 被引量:3
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作者 薛秋芳 陈娟娟 王爱丽 《兰州大学学报(自然科学版)》 CAS CSCD 北大核心 2007年第6期125-128,共4页
考虑将预条件(I+S_α)应用于AOR迭代法和2PPJ迭代法,得到这两种预条件迭代法的收敛性定理,并从理论上证明了它们较原方法提高了迭代的收敛速度.
关键词 预条件 aOR迭代法 2PPJ迭代法 弱正规分裂 非奇异M-矩阵
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