检索结果-内蒙古大学图书馆

9th Annual Conference on Theory and Applications of Models of Computation, TAMC 2012

作者： Wang, Lin Fernández Anta, Antonio Zhang, Fa Hou, Chenying Liu, Zhiyong Key Lab. of Intelligent Information Processing Institute of Computing Technology Chinese Academy of Sciences China Institute IMDEA Networks Spain China State Key Lab. for Computer Architecture Institute of Computing Technology Chinese Academy of Sciences China Graduate University of Chinese Academy of Sciences China

ISBN: (纸本)9783642299513

Energy consumption is an important issue in the design and use of networks. In this paper, we explore energy savings in networks via a rate adaptation model. This model can be represented by a cost-minimization network routing problem with discrete cost functions. We formulate this problem as an integer program, which is proved to be NP-hard. Then a constant approximation algorithm is developed. In our proposed method, we first transform the program into a continuous-cost network routing problem, and then we approximate the optimal solution by a two-step rounding process. We show by analysis that, for uniform demands, our method provides a constant approximation for the uniform network routing problem with discrete costs. A bicriteria network routing problem is also developed so that a trade-off can be made between energy consumption and network delay. Analytical results for this latter model are also presented. © 2012 Springer-Verlag.

关键词： Network routing

来源：评论

学校读者我要写书评

暂无评论

A Pilot Allocation Method of Jointing Cell Grouping and Alliance Game in Massive MIMO System

A Pilot Allocation Method of Jointing Cell Grouping and Alli...

引用

第二届材料科学应用与能源材料国际研讨会

作者： Feiyue Wang Hui Zhi Ziju Huang Key Lab of Computing Intelligent and Signal Processing(Ministry of Education) Anhui University

In order to improve the uplink channel estimation performance and reduce pilot contamination(PC),this paper proposes a pilot allocation method of jointing cell grouping and alliance game(JCG-AG) for massive multiple-input multiple-output(MIMO) cellular *** can be divided into two ***,by properly dividing all cells into different cell-groups,the users in different cell-groups are allocated different orthogonal pilot ***,the users in the same cell-group are further divided into several mutually disjoint *** belonging to different sub-alliances are allocated different pilots,and users belonging to the same sub-alliance reuse the same *** the second step,the alliance formation algorithm is used to suppress *** JCG-AG method takes practical application as the starting point,focuses on the random distribution of users,and uses the idea of alliance *** these make it more flexible and *** demonstrated in the simulation results,the JCG-AG method can greatly mitigate the PC and reduce the average mean square error(MSE) for all channel estimations in the uplink.

关键词： MSE red A Pilot Allocation Method of Jointing Cell Grouping and Alliance Game in Massive MIMO System

来源：评论

学校读者我要写书评

暂无评论

Wideband 10-port mimo antenna array for 5g metal-frame smartphone applications

引用

Progress In Electromagnetics Research C 2020年 104卷 229-240页

作者： Liu, Peng Sun, Yufa Liu, Tao Li, Qing Wang, Xuefeng Key Lab of Intelligent Computing & Signal Processing Ministry of Education Anhui University Hefei230601 China

A wideband 10-port multiple input multiple output (MIMO) antenna array operated below 6 GHz for the fifth generation (5G) metal-frame smartphones is presented and discussed in this paper. The proposed MIMO antenna array element is composed of a microstrip line with a tuning stub and rectangular slot. The size of the rectangular slot is only 15 mm × 2 mm (0.211λ0 × 0.028λ0, and λ0 is the wavelength with the resonance frequency of 4.2 GHz). U-shaped slots on the substrate are used to reduce the mutual coupling between the antenna elements. At the same time, in order to improve the radiation characteristics of the antenna arrays, narrow slits are etched in the metal-frame. The proposed antenna covers 3.3–5.5 GHz (S11 © 2020, Electromagnetics Academy. All rights reserved.

关键词： Antenna arrays

来源：评论

学校读者我要写书评

暂无评论

A new coupled-loop antenna for eight-band LTE/WWAN operation in ultra-thin laptop computer

引用

Progress In Electromagnetics Research C 2013年 42卷 229-238页

作者： Zhu, Xianbin Sun, Yufa Key Lab of Intelligent Computing and Signal Processing Ministry of Education Anhui University Hefei 230039 China

A new structure of coupled-fed loop antenna con- nected with two branch radiators for eight-band LTE/WWAN (LTE700/GSM850/900/1800/1900/UMTS/LTE2300/2500) operation in the ultra-thin laptop computer is presented. The two branch strips of the antenna are e±cient radiators and contributing multi-resonant modes to greatly enhance the bandwidth of the antenna. The proposed antenna on the top shielding metal wall of the laptop display, with a planar and compact size of 12:5 × 70 × 0:8mm3, is suitable to be embedded inside the casing of the laptop computer. The proposed antenna is fabricated and tested, and good radiation performances are obtained. Compared with the existing published antennas, the volume of the planar antenna is quite small.

关键词： Laptop computers

来源：评论

学校读者我要写书评

暂无评论

Design of reconfigurable monopole antenna with switchable dual band-notches for UWB applications

引用

Progress In Electromagnetics Research C 2019年 96卷 97-107页

作者： Li, Ji Sun, Yufa Key Lab of Intelligent Computing and Signal Processing Ministry of Education Anhui University Hefei230601 China

A reconfigurable antenna with on-demand single-band or dual-band rejection capability for ultra-wideband (UWB) applications is presented. A modified monopole structure is integrated with a U-shaped slot and an open-ended slot to realize band-rejection. The antenna operates in four modes: A full UWB (3.1–10.6 GHz) coverage antenna, a UWB antenna with a single-band WiMax or wide local area network (WLAN) rejection, and a UWB antenna with dual-band WiMax/WLAN rejection. On-demand single and dual-band rejections are implemented by controlling two slots using two PIN diodes. Thus, the adopted control technique is quite easy and requires low operating power. Details of the design process and reconfiguration mechanism are presented. The band-rejection performance is explained by return loss and surface current distribution at single-band mode. A prototype is built on a Rogers substrate and tested to validate the performances. The antenna exhibits stable radiation characteristics and almost flat gain responses across the whole band, while significantly gain reduction is achieved at the rejected bands. Therefore, this antenna is suitable for high-performance UWB systems in WiMax/WLAN dense environments with the aim to improve signal quality, system capacity, and communication efficiency. © 2019, Electromagnetics Academy. All rights reserved.

关键词： Monopole antennas

来源：评论

学校读者我要写书评

暂无评论

A broadband ±45◦ dual-polarized magneto-electric dipole antenna for 2G/3G/LTE/5G/WiMAX applications

引用

Progress In Electromagnetics Research C 2018年 86卷 153-165页

作者： Lu, Zongzheng Sun, Yufa Zhu, Haoran Huang, Fei Key Lab of Intelligent Computing & Signal Processing Ministry of Education Anhui University Hefei230601 China

A novel broadband ±45◦ dual-polarized magneto-electric (ME) dipole antenna is proposed for 2G/3G/LTE/5G (3.3–3.6 GHz)/WiMAX applications. The proposed antenna has Γ-shaped feeding strips to impart a wide impedance bandwidth for its special structure. Stable antenna gain and radiation pattern are realized by using a rectangular box-shaped reflector instead of planar one. The antenna is fabricated and measured. The measured results show that a common impedance bandwidth is 83% with standing-wave ratio (SWR) ≤ 1.5 from 1.59 to 3.83 GHz and port-to-port isolation larger than 25 dB within the bandwidth. The measured antenna gains vary from 8 to 10.8 dBi and from 8 to 10.6 dBi for port 1 and port 2, respectively. The antenna has nearly symmetrical radiation patterns with low back lobe radiation both in horizontal and vertical planes, and broadside radiation patterns with narrow beam can also be obtained. The proposed antenna can be used for multiband base stations in next generation communication systems. © 2018, Electromagnetics Academy. All rights reserved.

关键词： Bandwidth

来源：评论

学校读者我要写书评

暂无评论

A broadband dual-polarized magneto-electric dipole antenna for 2G/3G/LTE/WiMAX applications

引用

Progress In Electromagnetics Research C 2017年 73卷 127-136页

作者： Li, Zuming Sun, Yufa Yang, Ming Wu, Zhifeng Tang, Peiquan Key Lab of Intelligent Computing & Signal Processing Ministry of Education Anhui University Hefei230601 China

A novel broadband dual-polarized magneto-electric (ME) dipole antenna is proposed for 2G/3G/LTE/WiMAX applications. The proposed antenna has stair-shaped feeding strips to impart a wide impedance bandwidth to it and a rectangular box-shaped reflector to enhance its stability in radiation patterns and high gain over the operating frequencies. The measured results show that a common impedance bandwidth is 80% with standing-wave ratio (SWR) ≤ 1.5 from 1.68 to 3.92 GHz, and port-to-port isolation larger than 25 dB within the bandwidth. The measured antenna gains vary from 9.2 to 12 dBi and from 9.2 to 11.8 dBi for port 1 and port 2, respectively. The antenna has nearly symmetrical radiation patterns with low back-lobe radiation both in horizontal and vertical planes, and broadside radiation patterns with narrow beam can also be obtained. © 2017, Electromagnetics Academy. All rights reserved.

关键词： Dipole antennas

来源：评论

学校读者我要写书评

暂无评论

A compact multiband omnidirectional GNSS antenna for artillery projectile applications

引用

Progress In Electromagnetics Research C 2016年 62卷 149-156页

作者： Liu, Weiwei Sun, Yufa Zhou, Dong Hu, Shaoqi Yang, Ming Key Lab of Intelligent Computing and Signal Processing Ministry of Education Anhui University Hefei230601 China

A compact multiband omnidirectional antenna for the reception of GNSS signals on artillery projectiles is designed in this paper. The proposed antenna consists of a metallic cone comprising a T-shaped monopole. It exhibits a broad bandwidth from 1.22 GHz to 1.28 GHz and from 1.44 GHz to 1.75 GHz, covering GPS L1, Galileo E2-L1-E1, GLONASS G1 and G2, CNSS B1 and B3. Measured results show that an omnidirectional radiation pattern is achieved, and the non-circularity in the azimuthal plane (xy-plane) is less than 2 dB for all the desired bands. Then the measured 6 dB beamwidth is about 110◦ in the presence of a finite 20 millimeters (mm) radius ground plane. Such an antenna has the potential to be easily used for small artillery projectiles. © 2016, Electromagnetics Academy. All rights reserved.

关键词： Monopole antennas

来源：评论

学校读者我要写书评

暂无评论

A wideband omnidirectional horizontally polarized antenna for wireless applications

A wideband omnidirectional horizontally polarized antenna fo...

引用

International Conference on Microwave and Millimeter Wave Technology Proceedings

作者： Shixian Chen Yufa Sun Dong Zhou Key Lab of Intelligent Computing & Signal Processing Anhui University Hefei China

A wideband omnidirectional horizontally polarized (HP) antenna is proposed and investigated in this paper. The antenna is composed of four arc printed dipoles, a small circular patch, four tapered microstrip transmission lines and four pairs of parasitic strips. To verify the performance of the antenna, simulations and measurements are carried out and discussed. The measured results show that the proposed antenna exhibits a 10-dB impedance bandwidth of 59.3% (2.23- 4.11 GHz). With an omnidirectional radiation pattern in E-plane, the proposed antenna has a peak gain of around 2 dBi across the operational band. The low profile and compact design, along with omnidirectional radiation pattern, make it ideal for wireless applications operated within WLAN (2.4- 2.484 GHz) and WiMAX (2.3GHz, 2.5GHz and 3.5GHz) frequency bands.

关键词： Dipole antennas Antenna measurements Antenna radiation patterns Frequency measurement Transmission line measurements Broadband antennas Bandwidth

来源：评论

学校读者我要写书评

暂无评论

An omnidirectional circularly polarized patch antenna with bandwidth broadening

An omnidirectional circularly polarized patch antenna with b...

引用

International Conference on Microwave and Millimeter Wave Technology Proceedings

作者： Guangyang Xu Yufa Sun Ming Yang Weiwei Liu Dong Zhou Key Lab of Intelligent Computing & Signal Processing Anhui University Hefei China

In this article, an omnidirectional circularly polarized (CP) patch antenna with bandwidth broadening is proposed. The antenna is composed of a circular patch with four L-shaped slots, a ground plane loaded a metal sleeve and a set of conductive vias. In order to broaden the impedance bandwidth, four parasitic strips are also sequentially rotated around the patch. As a result, it exhibits an omnidirectional CP radiation in the azimuthal plane. To verify the design, a prototype operating at 2.4 GHz industrial, scientific and medical band (ISM band) has been fabricated and measured. Measurement results show that the proposed antenna can achieve a -10 dB impedance bandwidth of 8.2% (ranges from 2.33 to 2.53 GHz) and a 3 dB axial ratio (AR) bandwidth of 9.2% (ranges from 2.29 to 2.51 GHz) in the azimuthal plane. The results indicate that the proposed antenna is a good candidate for 2.4 GHz ISM band applications.

关键词： Antenna measurements Bandwidth Patch antennas Reflection coefficient Antenna radiation patterns Frequency measurement

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：