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  • Introduction+to+3G+Mobile+Communications

    The third generation (3G) mobile communication system is the next big thing in the world of mobile telecommunications. The first generation included analog mobile phones [e.g., Total Access Communications Systems (TACS), Nordic Mobile Telephone (NMT), and Advanced Mobile Phone Service (AMPS)], and the second generation (2G) included digital mobile phones [e.g., global system for mobile communications (GSM), personal digital cellular (PDC), and digital AMPS (D-AMPS)]. The 3G will bring digital multimedia handsets with high data transmission rates, capable of providing much more than basic voice calls.

    标签: Communications Introduction Mobile 3G to

    上传时间: 2020-05-27

    上传用户:shancjb

  • IP Multimedia Subsystem(IMS) Handbook

    Fixed-mobile.convergence.and.voice-data.networks.have.merged.next-gen- eration,.value-added.applications.and.integrated.multimedia.services,.com- bining. Web. browsing,. instant. messaging,. presence,. voice. over. IP,. video. conferencing,. application. sharing,. telephony,. unified. messaging,. multi- media.content.delivery,.etc..on.top.of.different.network.technologies..The. convergence.of.the.communications.networks.is.motivated.by.the.need.to. support.many.forms.of.digital.traffic.as.well.as.to.amortize.implementation. and.operational.costs.of.the.underlying.networks..Historically,.the.approach. to. build. and. deploy. multimedia. services. has. focused. upon. single-point. solutions..

    标签: Multimedia Subsystem Handbook IMS IP

    上传时间: 2020-05-27

    上传用户:shancjb

  • LTE, WiMAX and WLAN

    For nearly a hundred years telecommunications provided mainly voice services and very low speed data (telegraph and telex). With the advent of the Internet, several data services became mainstream in telecommunications; to the point that voice is becoming an accessory to IP-centric data networks. Today, high-speed data services are already part of our daily lives at work and at home (web surfing, e-mail, virtual private networks, VoIP, virtual meetings, chats...). The demand for high-speed data services will grow even more with the increasing number of people telecommuting.

    标签: WiMAX WLAN LTE and

    上传时间: 2020-05-27

    上传用户:shancjb

  • Mobile and Wireless Communications

    There are few technologies that have had a more profound effect on people’s lives than mobile communications. As recently as twenty years ago no one had a mobile phone, while today 1.4 billion men, women and children depend on them. This now exceeds the number of landline users, where it took the preceding one hundred years to reach the 1 billion mark. The ability to make mobile voice calls turns out to be the answer to a deeply felt need across different cultures who simply want to communicate.

    标签: Communications Wireless Mobile and

    上传时间: 2020-05-30

    上传用户:shancjb

  • Mobile Multimedia Communications Concepts

    Mobile multimedia communication is increasingly in demand because of the basic need to communi- cate at any time, anywhere, using any technology. In addition, to voice communication, people have a desire to access a range of other services that comprise multimedia elements—text, image, animation, high fidelity audio and video using mobile communication networks. To meet these demands, mobile communication technologies has evolved from analog to digital, and the networks have passed through a number of generations from first generation (1G) to fourth generation (4G).

    标签: Communications Multimedia Concepts Mobile

    上传时间: 2020-05-30

    上传用户:shancjb

  • Mobile+and+Wireless+Systems+Beyond+3G

    With the rapid growth of the wireless mobile applications, wireless voice has begun to challenge wireline voice, whereas the desire to access e-mail, surf the Web or download music (e.g., MP3) wirelessly is increasing for wireless data. While second generation (2G) cellular wireless systems, such as cdmaOne1, GSM2 and TDMA3, introduced digital technology to wireless cellular systems to deal with the increasing demand for wireless applications, there is still the need for more spectrally efficient technologies for two reasons. First, wireless voice capacity is expected to continue to grow. Second, the introduction of high-speed wireless data will require more bandwidth.

    标签: Wireless Systems Mobile Beyond and 3G

    上传时间: 2020-05-30

    上传用户:shancjb

  • Modeling+and+Analysis+of+Telecommunications

    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

  • Radio_Frequency_Modulation_Made_Easy

    By inventing the wireless transmitter or radio in 1897, the Italian physicist Tomaso Guglielmo Marconi added a new dimension to the world of communications. This enabled the transmission of the human voice through space without wires. For this epoch-making invention, this illustrious scientist was honored with the Nobel Prize for Physics in 1909. Even today, students of wireless or radio technology remember this distinguished physicist with reverence. A new era began in Radio Communications.

    标签: Radio Frequency Modulation

    上传时间: 2020-06-01

    上传用户:shancjb

  • Radio+Resource+Management+Strategies

    It is more than a decade since GSM was first commercially available. After some unexpected delay, it seems that finally UMTS is here to stay as a 3G system standardised by 3GPP, at least for another ten years. UMTS will enable multi-service, multi-rate and flexible IP native-based mobile technologies to be used in wide area scenarios and also pave the way for a smooth transition from circuit switched voice networks to mobile packet services.

    标签: Management Strategies Resource Radio

    上传时间: 2020-06-01

    上传用户:shancjb

  • Service Delivery Platforms

    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