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China Communications 2016年第4期13卷 1-13页

作者： WANG Jihong shi wenxiao College of Communication Engineering Jilin University

Capacity reduction is a major problem faced by wireless mesh networks. An efficient way to alleviate this problem is proper channel assignment. Current end-toend channel assignment schemes usually focus on the case where channels in distinct frequency bands are assigned to mesh access and backbone, but actually backbone network and access network can use the same IEEE 802.11 technology. Besides, these channel assignment schemes only utilize orthogonal channels to perform channel assignment, and the resulting network interference dramatically degrades network performance. Moreover, Internet-oriented traffic is considered only, and peerto-peer traffic is omitted, or vice versa. The traffic type does not match the practical network. In this paper, we explore how to exploit partially overlapped channels to perform endto-end channel assignment in order to achieve effective end-to-end flow transmissions. The proposed flow-based end-to-end channel assignment schemes can conquer the limitations aforementioned. Simulations reveal that loadaware channel assignment can be applied to networks with stable traffic load, and it can achieve near-optimal performance; Traffic-irrelevant channel assignment is suitable for networks with frequent change of traffic load,and it can achieve good balance between performance and overhead. Also, partially overlapped channels' capability of improving network performance is situation-dependent, they should be used carefully.

关键词： channel assignment: end-to-end partially overlapped channels load-aware traffic-irrelevant

On Channel Assignment for Multicast in Multi-Radio Multi-Channel Wireless Mesh Networks:A Survey

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China Communications 2015年第1期12卷 122-135页

作者： WANG Jihong shi wenxiao JIN Feng College of Communication Engineering Jilin University

The major challenge faced by wireless mesh networks is the capacity reduction caused by interference,and interference can be reduced or even eliminated through appropriate channel *** article presents a comprehensive survey of channel assignment schemes for multicast in multi-radio multi-channel wireless mesh *** analyze the state-of-the-art channel assignment schemes for multicast and provide comprehensive taxonomy of the latest *** general,we classify the channel assignment schemes for multicast into two types,that is,sequential multicast routing and channel assignment(SMRCA)and joint multicast routing and channel assignment(JMRCA).Detailed review of channel assignment schemes in each category is *** future research directions and corresponding solutions are also explored to motivate research interests in the field of channel assignment for multicast in wireless mesh networks.

关键词： multicast channel assignment interference partially overlapped channels

Implementation and decoding method of OCC system based on MIMO

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Optoelectronics Letters 2022年第1期18卷 18-23页

作者： SUN Yufeng shi wenxiao SHAO Xinrui LIU Wei LIU Anqi Department of Communications Engineering Jilin UniversityChangchun 130012China

The application of high-frame-rate cameras as well as the complex image processing techniques will lead to a series of problems,such as high system cost and long transmission *** this paper,we introduce narrow-band filtering technology to reduce the impact of optical noise and reduce the complexity of image processing from the physical *** also introduce multiple-input multiple-output(MIMO)technology into the optical camera communication(OCC)system to increase system transmission rate,and propose a light emitting diode(LED)array decoding algorithm based on the directional projection method to reduce the system *** accumulating the target pixel values in each row and column of the image,the proposed method then determines the position and boundary of the detected target to distinguish the target area from the *** results indicate that the communication distance can reach up to 5.5 m without error bits *** the LED array at the transmitter of this system flashes at a frequency of 12 Hz,the transmission rate can reach 126.32 bit/s.

关键词： MIMO communication system

The Research of Indoor Positioning Based on Visible Light Communication

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China Communications 2015年第8期12卷 85-92页

作者： WANG Chunyue WANG Lang CHI Xuefen LIU Shuangxing shi wenxiao DENG Jing College of Communication Engineering Jilin University University of North Carolina at Greensboro

The key techniques in indoor positioning based on visible light communication and the state of the art of this research were surveyed. First, the significance of indoor positioning based on visible light communication from two aspects of the limitations of current indoor positioning technology and the advantages of visible light communication was discussed; And then, the main four technology of indoor positioning based on visible light communication were summarized and the triangulation of RSS method and the principle of image positioning were introduced in detail; Next, the performance characteristics of various typical algorithms were compared and analyzed; In the end, several suggestions on future research of indoor positioning based on visible light communication were given.

关键词： visible light communication indoor positioning imaging positioning RSS

Stability of Tokamak Plasmas with Internal Transport Barriers against High Ideal Magnetohydrodynamic Ballooning Mode

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Southwestern Institute of Physics Annual Report

Southwestern Institute of Physics Annual Report 2006年第1期 108-110页

作者： shi Bingren QU wenxiao

High n （ the toroidal mode number） ballooning mode analysis is generally thought to be the most fundamental tool for the study of the magnetohydrodynamic （MHD） stability in magnetically confinement toroidal fusion devices. Very recently, new interest on ballooning mode study is put on the internal transport barrier （ITB） phenomena, an improved confinement structure characterized by a central negative shear region and a much smaller energy transport region near the minimum of q.

关键词：等离子体核反应装置核反应技术磁流体动力学

Decoding algorithm with multiple features based on optical camera communication system

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Optoelectronics Letters 2023年第2期19卷 65-71页

作者： ZHANG Junming shi wenxiao WANG Qiang LIU Anqi LIU Wei Department of Communications Engineering Jilin UniversityChangchun 130012China

The performance of decoding algorithm is one of the important influential factors to determine the communication quality of optical camera communication(OCC) system. In this paper, we first propose a decoding algorithm with adaptive thresholding based on the captured pixel values under an ideal environment, and then we further propose a decoding algorithm with multiple features, which is more suitable under the existence of the interference of light sources. The algorithm firstly determines the light-emitting diode(LED) array profile information by removing the interfering light sources through geometric features, and then identifies the LED state by calculating two grayscale features, the average gray ratio(AGR) and the gradient radial inwardness(GRI) of the LEDs, and finally obtains the LED state matrix. The experimental results show that the bit error ratio(BER) of the decoding algorithm with multiple features decreases from 1×10^(-2) to 5×10^(-4) at 80 m.

关键词： Decoding algorithm multiple features camera communication system

Analytic Anisotropic Toroidally Axi-symmetric Equilibria with Parallel Flow for Arbitrary Aspect Ratio and Large Triangularity

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Southwestern Institute of Physics Annual Report

Southwestern Institute of Physics Annual Report 2006年第1期 116-118页

作者： shi Bingren QU wenxiao LI Fangzhu

Though most of the studies on toroidally axi-symmetric equilibria are based on the scalar pressure assumption that leads to the usual Grad-Shafranov equation, the realistic plasma is generally more complicated and plasmas with anisotropic pressure are routinely encountered. On the other hand, effect of plasma flow on tokamak equilibrium has also been attracted much interests historically and there appear some new interests for non-static equilibria For purely toroidal flow case, some exact solutions had been reported before .

关键词：平行流体等离子体非均质压力核技术

Stability of Tokamak Equilibrium with Internal Transport Barrier against High n MHD Ballooning Mode

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Southwestern Institute of Physics Annual Report

Southwestern Institute of Physics Annual Report 2005年第1期 121-124页

作者： shi Bingren QU wenxiao DONG Jiaqi

Internal transport barriers （ITBs） are phenomena associated with improved confinement mode of tokamak plasmas. Within the region where the ITB locates, the plasma pressure has a large gradient while the magnetic shear s has a minimum so that within and near the ITB, the absolute value of the shear is very low. Physics involved is plentiful, from the macroscopic （ MHD ） stability, to the suppression of microscopic instabilities thought to be responsible for anomalous transport. The treatment of very low shear also poses some theoretical difficulties.

关键词： Internal transport barrier Ballooning stability Low shear stabilizing channel

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认知无线传感器网络分簇路由协议综述

通信学报 2018年第11期39卷 156-169页

作者：王继红石文孝东北电力大学电气工程学院吉林吉林132012 吉林大学通信工程学院吉林长春130012

路由协议能实现认知无线传感器网络(CRSN, cognitive radio sensor network)内部感知数据的有效汇聚传输,尤其是分簇路由协议能进一步降低路由选择的复杂度、提升网络可扩展性,对整体网络性能至关重要。因此,针对CRSN分簇路由协议进行... 详细信息

路由协议能实现认知无线传感器网络(CRSN, cognitive radio sensor network)内部感知数据的有效汇聚传输,尤其是分簇路由协议能进一步降低路由选择的复杂度、提升网络可扩展性,对整体网络性能至关重要。因此,针对CRSN分簇路由协议进行综述研究。首先,在简要介绍CRSN分簇概念和优势的基础上,阐述CRSN分簇算法设计考虑的主要因素。其次,探讨CRSN分簇路由协议设计面临的挑战及应遵循的基本设计原则。再次,系统的分析和总结CRSN分簇路由协议的研究现状。最后,指出CRSN分簇路由协议研究中亟待解决的问题及未来的研究方向。

关键词：认知无线传感器网络分簇路由协议信道分配跨层

基于室内地图推演与信号穿墙修正的定位优化方法

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通信学报 2022年第10期43卷 146-156页

作者：孙大洋石文孝张定国吉林大学通信工程学院吉林长春130012 巴斯大学自主机器人研究中心巴斯BA27AY

针对室内定位中信号穿墙非视距传播带来的测量误差问题,提出了一种穿墙测距与视距测距相混合的穿墙修正定位优化方法。在室内典型的隔墙非视距场景中,建立了近似拟合信号穿墙传播特性的测距模型,将穿墙入射角、墙体结构、介电常数、墙... 详细信息

针对室内定位中信号穿墙非视距传播带来的测量误差问题,提出了一种穿墙测距与视距测距相混合的穿墙修正定位优化方法。在室内典型的隔墙非视距场景中,建立了近似拟合信号穿墙传播特性的测距模型,将穿墙入射角、墙体结构、介电常数、墙体厚度等因素参数化,并借助室内地图进行节点与锚点间的隔墙判定,仅根据室内地图及冗余测距信息即可进行定位求解。仿真与UWB实测实验结果表明,在考虑信号穿墙传播的多变地图场景下,所提方法的室内定位平均精度优于加权最小二乘法的平方测距定位方法。

关键词：室内定位超宽带测距信号穿墙修正地图推演

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