检索结果-内蒙古大学图书馆

International Conference on wireless communications and Signal Processing (WCSP)

作者： Lei Wang Wen Tang Ting Qi Jingwu Cui Baoyu Zheng Key Lab of Broadband Wireless Communication and Sensor Network Technology Nanjing University of Posts and Telecommunications Ministry of Education China National and Local Joint Engineering Laboratory of RF Integration and Micro-Assembly Technology Nanjing University of Posts and Telecommunications China

ISBN: (数字)9781728172361

ISBN: (纸本)9781728172378

Non-orthogonal multiple access (NOMA) and heterogeneous network (HetNet) have been regarded as two promising technologies in 5G, which can support massive connectivity. Integrating NOMA technology into HetNet is an inevitable trend to achieve better spectral efficiency. However, interference control becomes more complicated due to the combination of these two technologies and the optimization of energy efficiency comes at the expense of spectral efficiency. Therefore, we develop a novel network scenario, which exploits the benefits of sectorization. In this paper, we aim to maximize the energy efficiency of the entire small cells in an uplink underlaying two-tier NOMA heterogeneous network with sectorization. Since this energy efficiency maximization problem is a mixed integer non-linear programming (MINLP) problem which is difficult to solve, it is decomposed into two subproblems. Firstly, we use the Lagrange dual method and Karush-Kuhn-Tucker (KKT) optimal conditions to obtain the closed-form power allocation solution. Secondly, a low-complexity subchannel allocation algorithm based on the greedy strategy is proposed. Simulation results show that our proposed scheme obtain significant energy efficiency gain and is superior to other existing schemes.

关键词： Resource management NOMA Uplink Base stations Heterogeneous networks Telecommunications Mathematical model

来源：评论

学校读者我要写书评

暂无评论

Robust Beamforming for IRS-assisted wireless communications under Channel Uncertainty

Robust Beamforming for IRS-assisted Wireless Communications ...

引用

IEEE Conference on wireless communications and networking

作者： Yongchang Deng Yuze Zou Shimin Gong Bin Lyu Dinh Thai Hoang Dusit Niyato School of Intelligent Systems Engineering Sun Yat-sen University China School of Electronic Information and Communications Huazhong University of Science and Technology China Key Laboratory of Ministry of Education in Broadband Wireless Communication and Sensor Network Technology Nanjing University of Posts and Telecommunications China School of Electrical and Data Engineering University of Technology Sydney Australia School of Computer Science and Engineering Nanyang Technological University Singapore

In this paper, we consider IRS-assisted transmissions from a multi-antenna access point (AP) to a receiver with uncertain channel information. By adjusting the magnitude of reflecting coefficients, the IRS can sustain its operations by harvesting energy from the AP's signal beamforming. Considering channel estimation errors, we model both the AP-IRS channel and the AP-IRS-receiver as a cascaded channel by norm-based uncertainty sets. This allows us to formulate a robust optimization problem to minimize the AP's transmit power, subject to the receiver's worst-case data rate requirement and the IRS's worst-case power budget constraint. Instead of using the alternating optimization (AO) method, we firstly propose a heuristic scheme to decompose the IRS's phase shift optimization and the AP's active beamforming. Based on semidefinite relaxations of the worst-case constraints, we further devise an iterative algorithm to optimize the AP's transmit beamforming and the magnitude of the IRS's reflecting coefficients efficiently by solving a set of semidefinite programs. Simulation results reveal that the AP requires a higher transmit power to deal with the channel uncertainty. Moreover, the negative effect of channel uncertainty can be alleviated by using a larger-size IRS.

关键词： wireless communication Uncertainty Array signal processing Simulation Transmitting antennas Channel estimation Receivers

来源：评论

学校读者我要写书评

暂无评论

Long-Distance Entanglement Purification for Quantum communication

引用

Physical Review Letters 2021年第1期126卷 010503-010503页

作者： Xiao-Min Hu Cen-Xiao Huang Yu-Bo Sheng Lan Zhou Bi-Heng Liu Yu Guo Chao Zhang Wen-Bo Xing Yun-Feng Huang Chuan-Feng Li Guang-Can Guo CAS Key Laboratory of Quantum Information University of Science and Technology of China Hefei 230026 People’s Republic of China CAS Center For Excellence in Quantum Information and Quantum Physics University of Science and Technology of China Hefei 230026 People’s Republic of China Institute of Quantum Information and Technology Nanjing University of Posts and Telecommunications Nanjing 210003 People’s Republic of China School of Science Nanjing University of Posts and Telecommunications Nanjing 210003 People’s Republic of China Key Lab of Broadband Wireless Communication and Sensor Network Technology Nanjing University of Posts and Telecommunications Ministry of Education Nanjing 210003 People’s Republic of China

High-quality long-distance entanglement is essential for both quantum communication and scalab.e quantum networks. Entanglement purification is to distill high-quality entanglement from low-quality entanglement in a noisy environment and it plays a key role in quantum repeaters. The previous significant entanglement purification experiments require two pairs of low-quality entangled states and were demonstrated in tabletop. Here we propose and report a high-efficiency and long-distance entanglement purification using only one pair of hyperentangled state. We also demonstrate its practical application in entanglement-based quantum key distribution (QKD). One pair of polarization spatial-mode hyperentanglement was distributed over 11 km multicore fiber (noisy channel). After purification, the fidelity of polarization entanglement arises from 0.771 to 0.887 and the effective key rate in entanglement-based QKD increases from 0 to 0.332. The values of Clauser-Horne-Shimony-Holt inequality of polarization entanglement arises from 1.829 to 2.128. Moreover, by using one pair of hyperentanglement and deterministic controlled-NOT gates, the total purification efficiency can be estimated as 6.6×103 times than the experiment using two pairs of entangled states with spontaneous parametric down-conversion sources. Our results offer the potential to be implemented as part of a full quantum repeater and large-scale quantum network.

关键词： Entanglement manipulation Optical quantum information processing Quantum communication Quantum optics Quantum protocols

来源：评论

学校读者我要写书评

暂无评论

Predicted decoupling for coexistence between WiFi and LTE in unlicensed band

TechRxiv

引用

TechRxiv 2020年

作者： Tian, Feng Yu, Yue Yuan, Xu Lyu, Bin Gui, Guan The Key Laboratory of Broadband Wireless Communication and Sensor Network Technology Ministry of Education Nanjing University of Posts and Telecommunications Nanjing210003 China University of Louisiana at Lafayette LafayetteLA70504 United States

wireless fidelity (WiFi) and long term evolution (LTE) coexistence system has attracted significant attention recently. However, most studies on coexistence only consider the issues about downlink performance and fairness between WiFi network and LTE network. In this paper, we take a comprehensive consideration of both the performance of WiFi and LTE, to propose a downlink/uplink decoupling (DUDe) scheme for the fairness of the coexistence system. Through the process of modeling construction, problem formulation with reformulation, solution and simulations, we illustrate that DUDe can achieve proportional fairness in terms of sum throughput and load balancing between uplink and downlink. In our decoupling model for coexistence between WiFi and LTE, resource allocation is under adaptive spectrum partitioning and users can access each network of WiFi and LTE. Moreover, to make our proposal more realistic, we adopt support vector machine (SVM) to predict the total number of users in WiFi and LTE coexistence system, where the predictive simulation shows its high prediction accuracy with low complexity. We further apply the prediction results to the optimization problem of DUDe. Simulation results manifest that the proposed DUDe scheme has better performance in terms of sum throughput. The sum throughput of DUDe scheme can come up to almost twice more than that of coupled association scheme. The result shows that DUDe can also achieve load balance between uplink and downlink in the coexistence system. © 2020, CC BY.

关键词： Support vector machines

来源：评论

学校读者我要写书评

暂无评论

Measurement-device-independent quantum key distribution with hyper-encoding

引用

Science China(Physics,Mechanics & Astronomy) 2019年第11期62卷 47-56页

作者： Zheng-Xia Cui Wei Zhong Lan Zhou Yu-Bo Sheng Schoool of Science Nanjing University of Posts and TelecommunicationsNanjing 210003China Key Lab of Broadband Wireless Communication and Sensor Network Technology Ministry of EducationNanjing University of Postsand TelecommunicationsNanjing 210003China Institute for Quantum Computing University of Waterloo200 University Ave WWaterloo ON N2L3G1Canada Institute of Quantum Information and Technology Nanjing University of Posts and TelecommunicationsNanjing 210003China

Measurement device-independent quantum key distribution(MDI-QKD) protocols are immune to all possible attacks on the photon detectors during quantum communication, but their key generation rates are low compared with those of other QKD *** each individual photon’s channel capacity is an efficient way to increase the key generation rate, and high-dimensional(HD) encoding is a powerful tool for increasing the channel capacity of photons. In this paper, we propose an HD MDI-QKD protocol with qudits hyper-encoded in spatial mode and polarization degrees of freedom(DOFs). In the proposed protocol, keys can be generated using the spatial mode and polarization DOFs simultaneously. The proposed protocol is unconditionally secure,even for weak coherent pulses with decoy states. The proposed MDI-QKD protocol may be useful for future quantum secure communication applications.

关键词： quantum communication measurement device-independent quantum key distribution high-dimensional hyper encoding

来源：评论

学校读者我要写书评

暂无评论

Research on Time Synchronization Method Under Arbitrary network Delay in wireless sensor networks

引用

Computers, Materials & Continua 2019年第9期61卷 1323-1344页

作者： Bing Hu Feng Xiang Fan Wu Jian Liu Zhe Sun Zhixin Sun Key Laboratory of Broadband Wireless Communication and Sensor Network Technology Nanjing University of Posts and TelecommunicationsNanjing210003China YuanTong Express Co.LTD Shanghai201705China Department of Computer Science Tuskegee UniversityTuskegeeAL36088USA College of Information Engineering Nanjing University of Finance and EconomicsNanjing210023China

To cope with the arbitrariness of the network delays,a novel method,referred to as the composite particle filter approach based on variational Bayesian(VB-CPF),is proposed herein to estimate the clock skew and clock offset in wireless sensor ***-CPF is an improvement of the Gaussian mixture kalman particle filter(GMKPF)*** GMKPF,Expectation-Maximization(EM)algorithm needs to determine the number of mixture components in advance,and it is easy to generate overfitting and *** Bayesian EM(VB-EM)algorithm is introduced in this paper to determine the number of mixture components adaptively according to the ***,to solve the problem of data packet loss caused by unreliable links,we propose a robust time synchronization(RTS)method in this *** establishes an autoregressive model for clock skew,and calculates the clock parameters based on the established autoregressive model in case of packet *** final simulation results illustrate that VB-CPF yields much more accurate results relative to GMKPF when the network delays are modeled in terms of an asymmetric Gaussian ***,RTS shows good robustness to the continuous and random dropout of time messages.

关键词： Time synchronization particle filter expectation maximization wireless sensor networks(WSNs)

来源：评论

学校读者我要写书评

暂无评论

18F-FDG PET RADIOMICS SCORE CONSTRUCTION BY AUTOMATIC MACHINE LEARNING FOR TREATMENT RESPONSE PREDICTION IN ELDERLY PATIENTS WITH DLBCL: A MULTICENTER STUDY

引用

Hematological Oncology 2025年第S3期43卷

作者： J. Zhao W. Zhao M. Chen J. Rong Y. Teng J. Chen J. Xu Department of Hematology Nanjing Drum Tower Hospital School of Basic Medicine and Clinical Pharmacy China Pharmaceutical University Nanjing China The Key Laboratory of Broadband Wireless Communication and Sensor Network Technology (Ministry of Education) Nanjing University of Posts and Telecommunications Nanjing China Department of Nuclear Medicine Nanjing Drum Tower Hospital Affiliated Hospital of Medical School Nanjing University Nanjing China

来源：评论

学校读者我要写书评

暂无评论

Arbitrary-Oriented Ship Detection Based on Rotation Region Locating networks in Large Scale Remote Sensing Images

Arbitrary-Oriented Ship Detection Based on Rotation Region L...

引用

International Conference on Image, Vision and Computing (ICIVC)

作者： Xipeng Liu Jianxin Chen Bin Kang Xuguang Zhang Key Lab of Broadband Wireless Communication and Sensor Network Technology Nanjing University of Posts and Telecommunications Nanjing China

ISBN: (纸本)9781728123264

Although deep learning has dominated the ship detection domain, it still has two challenges: arbitrary-oriented densely arranged ships cause detection omissions and large scale image contains redundant areas. This paper proposes an effective convolutional neural network framework for arbitrary-oriented ship detection in large scale and complex scenes. In this framework, we propose Cumulative Feature Pyramid networks for multi-receptive-field feature fusion, which enhances high-level semantic information at all scales. Based on the outputs of Region Proposal networks, Rotation Region Locating network predicts rotation bounding box of arbitrary-oriented ships and adopts rotation intersection over union to avoid the effect of ship dense arrangement. For large scale scenes, No-Ship Area Suppression uses OTSU algorithm to generate binary mask and then filter out non-ship regions to reduce redundant computations. Additionally, we firstly build a remote sensing image dataset for ship detection, which contains 4237 images and over 21200 ships. Experimental comparisons with the state-of-the-art approaches validate the effectiveness, accuracy and robustness of the proposed method.

关键词： Remote sensing Ship detection Deep learning Feature fushion Rotation region proposal Ships remote sensing remote sensing images Scale formation Machine Learning

来源：评论

学校读者我要写书评

暂无评论

Medical Image Grading Learning Based on Active and Incremental Fine-Tuning

Medical Image Grading Learning Based on Active and Increment...

引用

2019第十一届数字图像处理国际会议

作者： Zhuo Su Jiwei Hu Quan Liu Jiamei Deng School of Information Engineering Wuhan University of Technology Key Lab.of Broadband Wireless Communication and Sensor Network

The development of convolutional neural network has brought great achievements to image classification in recent ***,the classification performance is good only for natural images rather than medical *** important reason is that the medical image database used for training is always *** how to use these limited data to acquire more extensive features has become a hot research *** this paper,we first update the order and number of the whole training data every time in active and incremental *** we set different contribution rate for the data selected in our model,which based on the information quantity of the data in training stage and make our model converge *** that,a pre-trained model and our preprocessed datasets are employed,which allows us to further fine-tune our *** experiments evaluated on two different biomedical datasets shows that our model can achieve promising results.

关键词： Grading learning medical image multivariate training datasets

来源：评论

学校读者我要写书评

暂无评论

Voiceprint recognition based on BP Neural network and CNN 4

Voiceprint recognition based on BP Neural Network and CNN

引用

2019 4th International Conference on Intelligent Computing and Signal Processing, ICSP 2019

作者： Zhipeng, Dong Jingcheng, Wei Yumin, Xu Qingmin, Meng Xiaoming, Wang Key Laboratory of Broadband Wireless Communication and Sensor Network Technology Nanjing University of Posts and Telecommunications Ministry of Education College of Telecommunications and Information Engineering Nanjing210003 China National Mobile Communications Research Lab Southeast University Nanjing210096 China

At present, speech recognition has become a key technology of human-computer interaction, which can be used in semantic recognition and speaker identification and other related applications. This paper focuses on a speaker identification scene and the technical design. Because artificial neural network has the ability to distinguish complex classification boundaries, plenty of work on speech recognition had studied multi-layer perceptual networks to improve the accuracy of classification where back propagation method (BP algorithm) has been used. In the studied scheme, when the test objects (speakers) speak the same isolated word, the identification system can judge who the speaker is by identifying the voice voiceprint of different people. Our design not only considers the recognition based on BP as well as its variant, but also explores the voiceprint recognition based on convolution neural network (CNN). Secondly, the network structure and performance are also compared in detail. © 2019 IOP Publishing Ltd. All rights reserved.

关键词： Speech recognition

来源：评论

学校读者我要写书评

暂无评论

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

请选择保存的检索档案：

请选择收藏分类：

通借通还

建议与咨询 留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

请选择保存的检索档案： 新增检索档案 确定 取消

请选择收藏分类： 新增自定义分类 确定 取消

通借通还

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

请选择保存的检索档案：

请选择收藏分类：