Wireless Communication
Wireless communication(无线通信)
The application of wireless communication
LiFi technology
• Wi-Fi technology has been more and more popular, but more and more people complain that wireless signal is not stable, speed of internet is slow, Wi-Fi hotspots are too few. Now, there is a new technology may bring solutions.
Wireless communication
• The most common wireless technologies use radio. With radio waves distances can be short, such as a few meters for television or as far as thousands or even millions of kilometers for deep-space radio communications.
• A cellular network or mobile network is a communication network where the last link is wireless. The network is distributed over land areas called cells, each served by at least one fixed-location transceiver, known as a cell site or base station. This base station provides the cell with the network coverage which can be used for transmission of voice, data and others. In a cellular network, each cell uses a different set of frequencies from neighboring cells, to avoid interference and provide guaranteed bandwidth within each cell.
近距离无线通信技术zongjie
四、宽带无线接入技术
国际电子电气工程师协会(IEEE)成立了无线局域 网标准委员会，并于1997年制定出第一个无线局 域网标准——802.11。 1999年，IEEE成立了802.16工作组开始研究建立 一个全球统一的宽带无线接入城域网技术规范。
已经制定或正在制定的IEEE802.11、IEEE802.15、 IEEE802.20、IEEE802.22等宽带无线接入标准集， 覆盖了无线局域网(WLAN)、无线个域网 (WMAN)、无线城域网(WPAN)的领域。
高速近距离无线通信最高数据速率＞ 100Mbit/s，通信距离＜10m，典型技术 有高速超宽带（UWB）；
低速近距离无线通信的最低数据速率＜ 1Mbit/s，通信距离＜100m，典型技术有 Zigbee、Bluetooth等。
三、近距离无线通信技术
目前，比较受关注的近距离无线通信技 术包括蓝牙、802.11（Wi-Fi）、ZigBee、 红外（IrDA）、超宽带（UWB）、近距 场无线通信（Near Field Communication， NFC）等。
该频段RFID系统的工作特性如下：
工作频率不受无线电频率管制约束； 阅读距离一般情况下小于1m； 有较高的电感耦合功率可供电子标签使用； 无线信号可以穿透水、有机组织和木材等；
电感耦合方式
低频频段的RFID系统非常适合近距离、 低速度、数据量要求较少的识别应用。 典型应用为动物识别、容器识别、工具 识别、电子闭锁防盗等。
射频通信
一、什么是射频？ 射频(Radio Frequency，RF) 表示可以辐
射到空间的电磁波频率，通常所指的频 率范围为300KHz～30GHz。 射频的本质是射频电流，是一种高频交 流电的简称。
二、频谱的划分 ① IEEE划分的频谱 ② 微波和射频 ③ 工业、科学和医用频率
视听说,wireless,communication
The preview of the wireless communication future.
The preview of the wireless communication future.
◆ Hardware Design
Small, lightweight, low power, cheap, high frequency operation
the sales of their goods.
Wi-Fi
How doeswireless communication influence our l i f e ?
无线能量传输
Wireless energy transfer is a process whereby electrical energy is transmitt e from a power source to an electrica电l力l负o荷 ad that does not have a built-in power sourc without the use of interconnecting s There are two different fundamen 线 methods for wireless energy transfer. It can help us charge our digital product without wire which used to bother us a lot
Sumner Tainter invented and patented the photophone, a v. 取得…的
telep 音o机n； e 电at话机conducted au i利o权
conversations w声i音r的elessly over
无线通信英文版教学设计 (2)
无线通信英文版教学设计1. IntroductionWireless communication is the exchange of information between two or more devices without the use of cables or wires. Wireless communication is an essential part of modern life and has transformed the way we communicate. This course is designed to provide students with a solid foundation in wireless communication principles, practices, and technologies.2. Course ObjectivesThe objectives of this course are: - To introduce the fundamental principles of wireless communication. - To expln the different types of wireless communication systems and their applications. - To teach the basic concepts of radio frequency (RF) technology and wireless network architecture. - To discuss the various communication standards that govern wireless communication. - To provide hands-on experience in building wireless communication systems.3. Course OutlineThe course will cover the following topics:Week 1: Introduction to Wireless Communication•Overview of wireless communication•Types of wireless communication systems•Applications of wireless communicationWeek 2: Basic Concepts of Radio Frequency (RF) Technology•RF waves and signals•Modulation techniques•Demodulation techniquesWeek 3: Wireless Network Architecture•Wireless network topologies•Wireless access points and routers•Wireless network securityWeek 4: Wireless Communication Standards•IEEE 802.11 (Wi-Fi)•Bluetooth•Cellular networks (GSM, CDMA)Week 5: Building Wireless Communication Systems•Basic hardware components of a wireless communication system•Installing and configuring a wireless access point•Troubleshooting wireless network issues4. Teaching MethodologyThis course will be delivered through a combination of lectures, readings, assignments, and hands-on projects. Lectures will provide an introduction to the topic and cover the theoretical aspects of wireless communication. Readings will supplement the lectures and provide additional information on the course topics. Assignments will be given to evaluate the student’s understandin g of the course material. Hands-on projects will provide practical experience in building wireless communication systems.5. Assessment and GradingThe grade for this course will be based on the following components: Component WeightageAssignments 40%Hands-on Projects 30%Final Exam 30%6. References•Andreas F. Molisch,。
应用型大学英语视听说教程发展篇2 第四版 Unit 1Wireless Communication
听力原文
1. What are the outcomes of increasing use of smartphones?
The rise of smartphones is creating smarter consumers, creating more opportunities for smarter marketing.
Part Two Listening
Listening Skill
2）小数 规则：含小数点的数字，小数点“.”读做：point。 如：0.125 读做：nought point one two five 3）百分数 规则：读百分数只需在相应的数字后加“percent”。 如：45% 读做 forty-five percent 4. 年代及日期的读法 规则：数字表示的年份通常分成两半来说。 如：1558 读做：fifteen fifty-eight
Part One Lead-in
Group Work
视频 视频原文
Watch the video about the development of Microsoft’s smartwatches and try to fill in the blanks in the mind map below. After that you’re required to make a mini report based on the mind map you’ve finished within your group.
2. What would people give up to keep using smartphones?
Smartphones have become such an important part of our lives that many of us would give up high heels, cable TV, even chocolate, just to keep using them.
本科毕业论文中英文翻译--Wireless-Communications无线通信
Wireless Communications*byJoshua S. Gans, Stephen P。
King and Julian Wright1。
IntroductionIn 1895, Guglielmo Marconi opened the way for modern wireless communications by transmitting the three—dot Morse code for the letter ‘S' over a distance of th ree kilometers using electromagnetic waves。
From this beginning，wireless communications has developed into a key element of modern society. From satellite transmission, radio and television broadcasting to the now ubiquitous mobile telephone，wireless communications has revolutionized the way societies function.This chapter surveys the economics literature on wireless communications。
Wireless communications and the economic goods and services that utilise it have some special characteristics that have motivated specialised studies. First，wireless communications relies on a scarce resource –namely，radio spectrum –the property rights for which were traditionally vested with the state。
Wireless communication technology作文
Wireless communication technology作文案例一：The present development of telecommunication technology indicates that the smart antenna, software radio, and the transmission technology of subline 下行high-speed subdivided exchange data (下行高速分组交换数据传输技术) are key technologies for today’s mobile telecommunications. Software radio, in particular, has attracted much public attention. The use of DSP and software to solve the problem of wireless interfaces of diverse standards on a public hardware platform has become a major issue pursued by many professionals in our field. I too hope to make my own contribution to the technological development in this area. In the next few years, the traditional concept of using chips to build wireless equipment for mobile telecommunication will be seriously challenged. In recent years, the technologies and standards of the third generation of mobile telecommunication have been rapidly updated. Software radio, I believe, will be the future of our trade.My desire to know more about computer engineeringprompted me to rise above my present conditions. The United States, as technological superpower, have first-rate teaching faculty and research facilities in the world. Its ideological openness and tolerance make a sharp contrast to Chinese culture, which tends to value tradition rather than innovation. Wireless telecommunication may be said to be one of the newest research areas, and it is new concepts and new vision that give life to the industry. I believe that in the fine research environment in the United States, I will be able to make “shortcuts” in attaining my academic and career goals.I would like to apply for admission to the Center for Wireless Telecommunications of Virginia Polytechnic Institute and State University. As the most prestigious research institute in Wireless Telecommunications, the Center has a large number of famed scholars and professionals dedicated to the theoretic research of Wireless Telecommunications. Meanwhile, it maintains close contact with the telecommunication industry, and in this way can test the theory in practical experimentation, which in turn promotes theoretic research. It is an ideal place for me to fully develop my research potential.I look forward to finding a teaching position at college level in China after completing my graduate education, which will allow me to continue my research work in Wireless Telecommunications. I will impart my theoretic and practical knowledge to my students, and hope that this will benefit China’s wireless telecommun ication industry, and society at large. I will make every effort to make the idea of “personal communication” a reality.案例二：The influence of the communication technology in teenagers have deepened with the development it. This influence has both positive and negative impact. On the positive side, teenagers now can talk to strangers from all over the world and get to know different culture and customs, they also have better opportunity to learn foreign language. Also teenagers will have more chances to befriend someone. However this brings out the negative impact. Due to the nature of communication technology, teenagers befriend with someone they never seen before. This can be dangerous as the stranger can be a villain giving wrong impression of world to theteenagers and teenagers due to the young age, will accept the wrong impression and hence have bad influence.案例三：Three Kinds of CommunicationAs we all know,communication has been playing an important part in people's life.As far as I know there are many kinds of communication,among them mail,telephone and computer are most commonly used.Writing letters is one of them.People use it to exchange information,ideas and thoughts.Slow as the mail is,it is the cheapest means of communication.The second kind is the telephone.By using telephone,people can hear each other even if they are far away.With the development of modern science and technology,the computer has come into munication with computers is fast and easy.In this way,people can send E-mail to each other.In a word,mail,telephone and computer all help to bring people all over the world closer.。
无线网络方向期刊小结
1、IEEE WIRELESS COMMUNICATIONS简介：IEEE WIREL COMMUN杂志属于工程技术行业，“电信学”子行业的顶级杂志。
审稿速度：较慢，6-12周。
级别/热度：黑红。
MedSci评语：顶级杂志，所有评语，一个字：难。
出版周期Bimonthly影响因子：SCI(2011)：2.575 SCI(2010)：1.798 SCI(2009)：2.394 SCI(2008)：3.18 SCI(2007)：2 SCI(2006)：2.577 SCI(2005)：2.638 SCI(2004)：2.189 SCI(2003)：1.5832、IEEE NETWORK出版周期Bimonthly影响因子：SCI(2011)：2.239 SCI(2010)：1.934 SCI(2009)：2.148 SCI(2008)：3.068 SCI(2007)：1.609 SCI(2006)：2.211 SCI(2005)：2.792 SCI(2004)：2.667 SCI(2003)：3.8713、IET COMMUNICATIONS出版周期Bimonthly 双月刊影响因子：SCI(2011)：0.829 SCI(2010)：0.963 SCI(2009)：0.751 SCI(2008)：0.345研究方向：无线通信,多采样信号处理,认知无线电,审稿速度：网友总结平均3 个月的审稿周期稿件命中率：投稿平均命中率为65%这个期刊很好中，特别是加上一个编辑或者fellow作为coauthor后简直必中。
审稿人的意见不是最重要的，对于这个期刊编辑很重要。
投稿难度评价：影响因子低，但是接稿量大，容易发表审稿速度：偏慢，4-8周级别/热度：蓝评语：相对冷门，关注人不多。
4、IEEE/ACM Transactions on Networking (ToN)期刊简称IEEE ACM T NETWORK期刊出版周期Bimonthly投稿难度评价：影响因子不是很高，与此细分类别影响因子普遍偏低有关，但不代表容易投中，文章仍然需要一定的水平审稿速度：偏慢，4-8周级别/热度：暗红评语：杂志级别不错，但是比较冷门，关注人数偏少。
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Wireless LAN Categories
Infrared (IR) LANs Spread spectrum LANs
Narrowband microwave
Strengths of Infrared Over Microwave Radio
Spectrum for infrared virtually unlimited
Uses unlicensed ISM spectrum Used at low power (0.5 watts or less) Operates at 10 Mbps in the 5.8-GHz band
Range = 50 m to 100 m
Q&A
?
Possibility of high data rates
Infrared spectrum unregulated Equipment inexpensive and simple Reflected by light-colored objects
Ceiling reflection for entire room coverage
Ambient radiation appears as noise in an infrared
receiver Transmitters of higher power required Limited by concerns of eye safety and excessive power consumption Limits range
focusing Focused IR data link can have range of kilometers Cross-building interconnect between bridges or routers
Ominidirectional
Single base station within line of sight of all other stations on LAN Station typically mounted on ceiling Base station acts as a multiport repeater
LAN Extension
Wireless LAN linked into a wired LAN on same premises Wired LAN
Backbone Support servers and stationary workstations Wireless LAN Stations in large open areas Manufacturing plants, stock exchange trading floors, and warehouses
Uses:
Transfer data from portable computer to office
server Extended environment such as campus
Ad Hoc Networking
Temporary peer-to-peer network set up to meet immediate need Example:
Multiple-cell Wireless LAN
Cross-Building Interconnect
Connect LANs in nearby buildings
Wired or wireless LANs
Point-to-point wireless link is used
Licensed within specific geographic areas to avoid potential interference Motorola - 600 licenses in 18-GHz range
Covers all metropolitan areas Can assure that independent LANs in nearby
CSMA Appropriate for ad hoc LANs
Spread Spectrum LAN Configuration
Hub topology Mounted on the ceiling and connected to backbone May control access May act as multiport repeater Automatic handoff of mobile stations Stations in cell either: Transmit to / receive from hub only Broadcast using omnidirectional antenna
Narrowband Microwave LANs
Use of a microwave radio frequency band for signal transmission Relatively narrow bandwidth Licensed Unlicensed
Licensed Narrowband RF
locations don’t interfere Encrypted transmissions prevent eavesdropping
Unlicensed Narrowband RF
RadioLAN introduced narrowband wireless LAN in 1995
All IR transmitters focused and aimed at a point on diffusely reflecting ceiling IR radiation strikes ceiling
Reradiated omnidirectionally Picked up by all receivers
Group of employees with laptops convene for a
meeting; employees link computers in a temporary network for duration of meeting
Wireless LAN Requirements
Doesn’t penetrate walls
More easily secured against eavesdropping Less interference between different rooms
Drawbacks of Infrared Medium
Indoor environments experience infrared background radiation Sunlight and indoor lighting
Devices connected are typically bridges or routers
Nomadic Access
Wireless link between LAN hub and mobile data terminal equipped with antenna
Laptop computer or notepad computer
IR Data Transmission Techniques
Directed Beam Infrared Ominidirectional
Diffused
Directed Beam Infrared
Used to create point-to-point links Range depends on emitted power and degree of
Throughput Number of nodes Connection to backbone LAN Service area Battery power consumption Transmission robustness and security Collocated network operation License-free operation Handoff/roaming Dynamic configuration
Wireless LAN Technology
Chapter 13
WIRELESS LAN TECHNOLOGY
Wireless LAN Applications
LAN Extension Cross-building interconnect
working
Wireless Communication
Background of Wireless Communication
Wireless Communication Technology
Wireless Networking and Mobile IP
Wireless Local Area Networks Student Presentations and Projects
Ceiling transmitter broadcasts signal received by
IR transceivers IR transceivers transmit with directional beam aimed at ceiling base unit
Diffused
Spread Spectrum LAN Configuration
Multiple-cell arrangement (Figure 13.2) Within a cell, either peer-to-peer or hub
Peer-to-peer topology