From the transition of analog to digital communication along with seamless mobility and high computing power of small handheld devices, the wireless communications industry has seen tremendous changes leading to the integration of several telecommunication networks, devices and services over last 30 years. The rate of this progress and growth has increased particularly in the past decade because people no longer use their devices and networks for voice only, but demand bundle contents such as data download/streaming, HDTV, HD video , 3D video conferencing with higher efficiency, seamless connectivity, intelligence, reliability and better user experience. Although the challenges facing service providers and telecommunication companies differ by product, region, market size, and their areas of concentration but time to market, efficient utilization of their assets and revenue expansion, have impacted significantly how to manage and conduct their business while maintaining sufficient margin.
标签: Convergence Networks Beyond 4G of
上传时间: 2020-05-26
上传用户:shancjb
At present, there is a strong worldwide push toward bringing fiber closer to indi- vidual homes and businesses. Fiber-to-the-Home/Business (FTTH/B) or close to it networks are poised to become the next major success story for optical fiber com- munications. In fact, FTTH connections are currently experiencing double-digit or even higher growth rates, e.g., in the United States the annual growth rate was 112% between September 2006 and September 2007, and their presence can add value of U.S. $4,000–15,000 to the selling price of a home.
标签: Technologies Broadband Networks Access
上传时间: 2020-05-26
上传用户:shancjb
This books presents the research work of COST 273 Towards Mobile Broadband Multimedia Networks, hence, it reports on the work performed and on the results achieved within the project by its participants. The material presented here corresponds to the results obtained in four years of collaborative work by more than 350 researchers from 137 institutions (universities, operators, manufacturers, regulators, independent laboratories and others – a full list is provided in Appendix B) belonging to 29 countries (mainly European, but also from Asia and North America) in the area of mobileradio. Theobjectiveofpublishingtheseresultsasabookisessentiallytomakethemavailable to an audience wider than the project. In fact, it just follows a ‘tradition’ of previous COST Actions in this area of telecommunications, i.e. COST 207, 231 and 259.
标签: Multimedia Techniques Broadband Networks Mobile
上传时间: 2020-05-30
上传用户:shancjb
The insinuation of telecommunications into the daily fabric of our lives has been arguably the most important and surprising development of the last 25 years. Before this revolution, telephone service and its place in our lives had been largely stable for more than a generation. The growth was, so to speak, lateral, as the global reach of telecommunications extended and more people got telephone service. The distinction between oversea and domestic calls blurred with the advances in switching and transmission, undersea cable, and communication satellites. Traffic on the network remained overwhelmingly voice, largely in analog format with facsimile (Fax) beginning to make inroads.
标签: Telecommunications Modeling Analysis and of
上传时间: 2020-05-31
上传用户:shancjb
Convergence between the two largest networks (Telecom and IP) is taking place very rapidly and at diff erent levels: (1) network level: unifi cation of IP networks with traditional Telecom networks through evolving standards (Session Initiation Protocol (SIP), Realtime Transfer Protocol (RTP), SS7, 3G) to support interopera- bility; (2) service level: traditional Telecom services like voice calls are being provi- sioned on the IP backbone (VoIP), while traditional IP services (most data-driven services such as multimedia, browsing, chatting, gaming, etc.) are accessible over the Telecom network.
标签: Platforms Delivery Service
上传时间: 2020-06-01
上传用户:shancjb
In this thesis several asp ects of space-time pro cessing and equalization for wire- less communications are treated. We discuss several di?erent metho ds of improv- ing estimates of space-time channels, such as temp oral parametrization, spatial parametrization, reduced rank channel estimation, b o otstrap channel estimation, and joint estimation of an FIR channel and an AR noise mo del. In wireless commu- nication the signal is often sub ject to intersymb ol interference as well as interfer- ence from other users.
标签: Communications Space-Time Processing Wireless for
上传时间: 2020-06-01
上传用户:shancjb
Electrostatic discharge (ESD) phenomena have been known to mankind since Thales of Miletus in approximately 600 B.C.E. noticed the attraction of strands of hay to amber. Two thousand six hundred years have passed and the quest to obtain a better under- standing of electrostatics and ESD phenomenon continues. Today, the manufacturing of microelectronics has continued the interest in the field of electrostatic phenomenon spanning factory issues, tooling, materials, and the microelectronic industry
上传时间: 2020-06-05
上传用户:shancjb
This book on electrostatic discharge phenomena is essentially a translation and update ofa Swedish edition from 1992. The book is intended for people working with electronic circuits and equipments, in application and development. All personnel should be aware of the ESD-hazards, especially those responsible for quality. ESD-prevention is a part of TQM (Total Quality Management). The book is also usable for courses on the subject.
标签: Electronics Scourge ESD The of
上传时间: 2020-06-05
上传用户:shancjb
Over the past few decades there has been an exponential growth in service robots and smart home technologies, which has led to the development of exciting new products in our daily lives. Service robots can be used to provide domestic aid for the elderly and disabled, serving various functions ranging from cleaning to enter- tainment. Service robots are divided by functions, such as personal robots, field robots, security robots, healthcare robots, medical robots, rehabilitation robots and entertainment robots. A smart home appears “intelligent” because its embedded computers can monitor so many aspects of the daily lives of householders. For example, the refrigerator may be able to monitor its contents, suggest healthy alter- natives and order groceries. Also, the smart home system may be able to clean the house and water the plants.
标签: Robotics Service Digital within Home the
上传时间: 2020-06-06
上传用户:shancjb
用三点法实现机器人三维位置测量的研究摘 要 :提 出 了一 种 微 小 爬 壁 机 器 人 三 维 位 置 测 量 的新 方 法 。笔 者 通 过 深 入 分 析 研 究各 种 位 置 测 控 方 法 与 系 统 ,提 出采 用单 目视 觉方 法 中的 聚 焦法 ,以 CCD作 为 传 感 器 ,用 三 点 法 实现 对 机 器 人 的 三 维 位 置 测 量 。 验 证性 实验 结果表 明 ,本研 究提 出的测 量原 理和 系统是 正 确 可行 的 。 关键词 :机 器人 ;位置 测量 ;CCD传 感 器 ;单 目视 觉 ;摄 像 机 标 定 中 图分 类 号 :TP242.6 文 献 标 识 码 :B Abstract:A new 3D position measurementmethod Ofa wall—climbing micro robothas been researched.Researc— hing on the various position measuring and controlling method,theauthorhasputforwardanewprojecttomeas— ure the 3D position of the robot,in which the focusing method with singlecamera and CCD sensorhasbeen used to getthe position information.The elementary experiment has verified the principle and the system. Key words:robot;position detection;CCD sensor;single camera vision;camera caiibration 位置测量技 术是智 能机 器人 的关键 技术 ,是各 种 机器人控 制系统 中极 为重 要 的环节 ,也 是 国内外研 究 的热点所 在。 按 照测试 系统 与被 测机 器 人 的关 系 ,可 以将位 置 测量技术 分为接触 式和非接触式 两大类 。接触 式测量 系统 由于在测 量过程 中或多或少地 对机器人施 加 了载 荷 ,因而仅适用于静 态 位置测 量 。而动 态 位 置测量 系 统 主要分 5类 :①激光跟踪 系统 ;@ CCD交 互测量 收 稿 日期 :2001—07—03 基 金项 目:国家 863高科技 研 究 资助 项 目(9804-06);教 育 部 高 等 学校 骨干教 师 资助 计 3t,j项 目 作者 简 介 :张 智海 (1973一 ),男 ,工 学硕 士 ,主 要 研 究 方 向 为 智 能 机 器人 测 控 技 术 。 系统 ;③ 超声波 测量 系统 ;④ PSD(positionsensitivede— vice)位 置 测 量 系统 ;⑤ 带 有 接 近觉 传 感 器 的 测量 系 统 。位置测量 还可 以从另一个分类 角度划分为主动式 测量和被动 式测 量 。主动式测 量主要可 以分为结 构光方法和激光 自动聚焦法两类 。被 动式测量 主要 可 以分为双 目视 觉 、三 目视觉 、单 目视觉 等方法 。 对 比以上各种方法 的 优缺 点 ,针对 笔者 研制 的微 小爬壁机器人 的空 间三 维位 置 测量 的要 求 ,测量 系统 必须满足尺 寸小 、分 辨率 高 、稳定 性 和可 靠性 好 、时 间 响应快等特 点 ,提 出了采用 单 目视觉方法 中的聚焦法 , 选用 CCD作 为传感器 ,用 三点法实现对机器人 的三维 位置测量 ,并用 Matlab和 V
标签: 机器人
上传时间: 2022-02-12
上传用户: