17-02-2011, 01:56 PM
hae i need complete report of this topic...
17-02-2011, 01:56 PM
hae i need complete report of this topic...
21-02-2011, 03:07 PM
4g ppt.ppt (Size: 4.48 MB / Downloads: 332) The Evolution of TDMA to 3G & 4G Wireless Systems AT&T Wireless Services AT&T serves over 14 million subscribers with digital TDMA technology and some remaining analog technology,and provides packet data service with CDPD technology • TDMA – European GSM over 250 million – North American TDMA ~ 50 million – Japanese PDC ~ 50 million • CDMA – North American CDMA ~ 60 million (including S. Korea) • Other TDMA operators • - Rogers AT&T • - Cingular (SBC & BellSouth) • - throughout Mexico, Central & South America Cellular Telephony Handsets TDMA parameters • 30 KHz channels (like analog & CDPD) • 20 msec speech frames • 24.3 kbaud symbol rate • 3 time-slots/users • 7.4 kbps ACELP speech coding • 1/2-rate channel coding on important bits interleaved over 2 bursts in 40 msec • Differential pi/4-QPSK modulation TDMA Capacity Roadmap • Operation at 800 or 1900 MHz. Calls can be set up on either frequency band and handed between them to manage traffic • Additional spectrum at 1900 MHz adds directly to capacity of cell • Smart Antennas u Base station antennas systems that use digital signal processing to cancel interference 4g.docx (Size: 23.41 KB / Downloads: 107) ABSTRACT 4G (also known as Beyond 3G), an abbreviation for Fourth-Generation, is a term used to describe the next complete evolution in wirelesscommunications. A 4G system will be able to provide a comprehensive IP solution where voice, data and streamed multimedia can be given to users on an "Anytime, Anywhere" basis, and at higher data rates than previous generations. As the second generation was a total replacement of the first generation networks and handsets; and the third generation was a total replacement of second generation networks and handsets; so too the fourth generation cannot be an incremental evolution of current 3G technologies, but rather the total replacement of the current 3G networks and handsets. The international telecommunications regulatory and standardization bodies are working for commercial deployment of 4G networks roughly in the 2012-2015 time scale. There is no formal definition for what 4G is; however, there are certain objectives that are projected for 4G. These objectives include, that 4G will be a fully IP-based integrated system. 4G will be capable of providing between 100 Mbit/s and 1 Gbit/s speeds both indoors and outdoors, with premium quality and high security. 1.INTRODUCTION The approaching 4G (fourth generation) mobile communication systems are projected to solve still-remaining problems of 3G (third generation) systems and to provide a wide variety of new services, from high-quality voice to high-definition video to high-data-rate wireless channels. The term 4G is used broadly to include several types of broadband wirelessaccess communication systems, not only cellular telephone systems. One of the terms used to describe 4G is MAGIC—Mobile multimedia, anytime anywhere, Global mobility support, integrated wireless solution, and customized personal service. As a promise for the future, 4G systems, that is, cellular broadband wireless access systems, have been attracting much interest in the mobile communication arena. The 4G systems not only will support the next generation of mobile service, but also will support the fixed wireless networks. This paper presents an overall vision of the 4G features, framework, and integration of mobile communication. The features of 4G systems might be summarized with one word-Integration.The 4G systems are about seamlessly integrating terminals, networks, andapplications to satisfy increasing user demands. The continuous expansion of mobile communication and wireless networks shows evidence of exceptional growth in the areas of mobile subscriber, wireless network access, mobile services, and applications. An estimate of 1 billion users by the end of 2003 justifies the study and research for 4G systems. 2.HISTORY The history and evolution of mobile service from the 1G (first generation) to fourth generation are discussed in this section. Table 1 presents a short history of mobile telephone technologies. This process began with the designs in the 1970s that have become known as 1G. The earliest systems were implemented based on analog technology and the basic cellular structure of mobile communication. Many fundamental problems were solved by these early systems. Numerous incompatible analog systems were placed in service around the world during the 1980s.The 2G (second generation) systems designed in the 1980s were still used mainly for voice applications but were based on digital technology, including digital signal processing techniques. These 2G systems provided circuit-switched data communication services at a low speed. The competitive rush to design and implement digital systems led again to a variety of different and incompatible standards such as GSM (global system mobile), mainly in Europe; TDMA (time division multiple access) (IS-54/IS-136) in the U.S.; PDC (personal digital cellular) in Japan; and CDMA (code division multiple access) (IS-95), another U.S. system. These systems operate nationwide or internationally and are today's mainstream systems, although the data rate for users in these system is very limited. During the 1990s, two organizations worked to define the next, or 3G, mobile system, which would eliminate previous incompatibilities and become a truly global system. The 3G system would have higher quality voice channels, as well as broadband data capabilities, up to 2 Mbps. Unfortunately, the two groups could not reconcile their differences, and this decade will see the introduction of two mobile standards for 3G. In addition, China is on the verge of implementing a third 3G system. An interim step is being taken between 2G and 3G, the 2.5G. It is basically an enhancement of the two major 2G technologies to provide increased capacity on the 2G RF (radio frequency) channels and to introduce higher throughput for data service, up to 384 kbps. A very important aspect of 2.5G is that the data channels are optimized for packet data, which introduces access to the Internet from mobile devices, whether telephone, PDA (personal digital assistant), or laptop. However, the demand for higher access speed multimedia communication in today's society, which greatly depends on computer communication in digital format, seems unlimited. According to the historical indication of a generation revolution occurring once a decade, the present appears to be the right time to begin the research on a 4G mobile communication system. 3.VISION OF 4G This new generation of wireless is intended to complement and replace the 3G systems, perhaps in 5 to 10 years. Accessing information anywhere, anytime, with a seamless connection to a wide range of information and services, and receiving a large volume of information, data, pictures, video, and so on, are the keys of the 4G infrastructures. The future 4G infrastructures will consist of a set of various networks using IP (Internet protocol) as a common protocol so that users are in control because they will be able to choose every application and environment. Based on the developing trends of mobile communication, 4G will have broader bandwidth, higher data rate, and smoother and quicker handoff and will focus on ensuring seamless service across a multitude of wireless systems and networks. The key concept is integrating the 4G capabilities with all of the existing mobile technologies through advanced technologies. Application adaptability and being highly dynamic are the main features of 4G services of interest to users. These features mean services can be delivered and be available to the personal preference of different users and support the users' traffic, air interfaces, radio environment, and quality of service. Connection with the network applications can be transferred into various forms and levels correctly and efficiently. The dominant methods of access to this pool of information will be the mobile telephone, PDA, and laptop to seamlessly access the voice communication, high-speed information services ,and entertainment broadcast services. Figure 1 illustrates elements and techniques to support the adaptability of the 4G domain. The fourth generation will encompass all systems from various networks, public to private; operator-driven broadband networks to personal areas; and ad hoc networks. The 4G systems will interoperate with 2G and 3G systems, as well as with digital (broadband) broadcasting systems. In addition, 4G systems will be fully IP-based wireless Internet. This allencompassing integrated perspective shows the broad range of systems that the fourth generation intends to integrate, from satellite broadband to high altitude platform to cellular 3G and 3G systems to WLL (wireless local loop) and FWA (fixed wireless access) to WLAN(wireless local area network) and PAN (personal area network),all with IP as the integrating mechanism. With 4G, a range of new services and models will be available. These services and models need to be further examined for their interface with the design of 4G systems. Figures 2 and 3 demonstrate the key elements and the seamless connectivity of the networks. 4.KEY 4G TECHNOLOGIES Some of the key technologies required for 4G are briefly described below: 4.1 OFDMA Orthogonal Frequency Division Multiplexing (OFDM) not only provides clear advantages for physical layer performance, but also a framework for improving layer 2 performance by proposing an additional degree of free- dom. Using ODFM, it is possible to exploit the time domain, the space domain, the frequency domain and even the code domain to optimize radio channel usage. It ensures very robust transmission in multi-path environments with reduced receiver complexity. OFDM also provides a frequency diversity gain, improving the physical layer performance .It is also compatible with other enhancement Technologies, such as smart antennas and MIMO.OFDM modulation can also be employed as a multiple access technology (Orthogonal Frequency Division Multiple Access; OFDMA). In this case, each OFDM symbol can transmit information to/from several users using a different set of sub carriers (sub channels). This not only provides additional flexibility for resource allocation (increasing the capacity), but also enables cross-layer optimization of radio link usage. 4.2 SOFTWARE DEFINED RADIO Software Defined Radio (SDR) benefits from today’s high processing power to develop multi-band, multi-standard base stations and terminals. Although in future the terminals will adapt the air interface to the available radio access technology, at present this is done by the infrastructure. Several infrastructure gains are expected from SDR. For example, to increase network capacity at a specific time (e.g. during a sports event),an operator will reconfigure its network adding several modems at a given Base Transceiver Station (BTS). SDR makes this reconfiguration easy. In the context of 4G systems, SDR will become an enabler for the aggregation of multi-standard pico/micro cells. For a manufacturer, this can be a powerful aid to providing multi-standard, multi-band equipment with reduced development effort and costs through simultaneous multi-channel processing. 4.3 MULTIPLE-INPUT MULTIPLE –OUTPUT MIMO uses signal multiplexing between multiple transmitting antennas (space multiplex) and time or frequency. It is well suited to OFDM, as it is possible to process independent time symbols as soon as the OFDM waveform is correctly designed for the channel. This aspect of OFDM greatly simplifies processing. The signal transmitted by m antennas is received by n antennas. Processing of the received signals may deliver several performance improvements:range, quality of received signal and spectrum efficiency. In principle, MIMO is more efficient when many multiple path signals are received. The performance in cellular deployments is still subject to research and simulations.However, it is generally admitted that the gain in spectrum efficiency is directly related to the minimum number of antennas in the link. 4.4 HANDOVER AND MOBILITY Handover technologies based on mobileIP technology have been considered for data and voice. Mobile IP techniques are slow but can be accelerated with classical methods (hierarchical, fast mobile IP). These methods are applicable to data and probably also voice. In single-frequency networks, it is necessary to reconsider the handover methods. Several techniques can be used when the carrier to interference ratio is negative (e.g. VSFOFDM,bit repetition), but the drawback of these techniques is capacity. In OFDM, the same alternative exists as in CDMA, which is to use macro-diversity. In the case of OFDM, MIMO allows macro-diversity processing with performance gains. However, the implementation of macro-diversity implies that MIMO processing is centralized and transmissions are synchronous. This is not as complex as in CDMA, but such a technique should only be used in situations where spectrum is very scarce. 5.QUALITY OF SERVICE _ Traffic generated by the different services will not only increase traffic loads on the networks, but will also require different quality of service (QoS) requirements (e.g., cell loss rate, delay, and jitter) for different streams (e.g., video, voice, data).
23-02-2011, 02:58 PM
I m Adil Khan a computer science engineering student
and i want to this report for 4g topic for my presntation in my college. so plz. send this report my email id afridi021[at]gmail.com thanks...
24-02-2011, 02:51 PM
presented by:
SONIA CHOUDHARY 4g1.ppt (Size: 1.32 MB / Downloads: 103) PRESENTATION ON 4G-Technology Key Business Trends 1. Global Telecom Spending Patterns Realigning o Early growth in international capex, US capex lag 2. Rise in Mobile Data Revenues Internationally o ARPUs up by 25% CAGR, US [< 5% CAGR] 3. 50% Rise in Mobile Voice Subscribers [+1.4B] o International +100%, US +15% o Emerging markets to remain unsaturated through 2012 o Mobile broadband subscribers up 275% [+750M] 4. New Mobile Services Taking Hold – SK/Japan/Nordics o Provide impetus to mobile data services 5. Operators Consolidating Domestically While Expanding Overseas o E.g., AT&T Mobility B India, Telefonica (+TIM) B CALA The 4G • What we need o Adaptive high performance transmission system o Great candidate for SDR Goal: A Unified Architecture 3G: Some Unfinished Business Technical • Improved coverage (e.g., residences) • Inter technology roaming Inter carrier compensation (esp. data services) Financial • Balance sheet cleanup (debt reduction) • Capacity Utilization • Business Models for New Services
25-02-2011, 09:29 AM
presented by:
Sudha Madhuri.Sattiraju Asha Jyothi.Koganti 4G1(SudhaMashuri).doc (Size: 712 KB / Downloads: 97) Abstract: Mobile devices are getting smaller, lighter, and more powerful; they have bigger screens and longer battery life, more features and more capabilities. Things like watching the football game on your mobile device, watching movies, videoconferencing, paying your bills and downloading music to the palm of your hand will become second nature in the near future. Bandwidth will always be the limiting factor in the development of applications and devices, be it wired, or wireless. At the moment the wireless world doesn’t have a large-cell, high bandwidth standard, that is capable of delivering the much needed speeds to a mobile device. The short fall of 3G networks is clear, it’s just not fast enough, offering 384kbps doesn’t meet the requirements of what the end user has come to expect these days. Some people see 3G as a stop-gap, until a fully integrated IP network is created; some countries have even chosen to bypass 3G and head straight to 4G, a method which has its advantages, and its disadvantages. 4G is set to be available around 2010, getting it right first time will make it a general winner with the one billion mobile users around the world. The end user can expect low cost per data bit, as well as speed and reliability, something which is greatly. Technology Companies with 4G networks are knocking on the door and mobile operators are beginning to answer. 4G networks and Next Generation Networks (NGNs) are becoming fast and very cost-effective solutions for those wanting an IP built high-speed data capacities in the mobile network. IP is pushing its way into the mobile wireless market,” said Visant Strategies Senior Analyst Andy Fuertes, author of “The Road to 4G and NGN: Wireless IP Migration Paths.” By 2010, the just-published study finds, there will be 113 million NGN and 4G users, with the market starting to take effect 2006 and 2007. Introduction: 4G is an initialize of the term Fourth-Generation Communications System. A 4G system will provide an end-to-end IP solution where voice, data and streamed multimedia can be served to users on an "Anytime, Anywhere" basis at higher data rates than previous generations. No formal definition is set as to what 4G is, but the objectives that are predicted for 4G can be summarized as follows 4G will be a fully IP-based integrated system of systems and network of networks wired and wireless networks (e.g.: computer, consumer electronics, communication technology…) Providing 100 Mbit/s and 1 Gbit/s, respectively, in outdoor and indoor environments End-to-end quality of service High security Offering any kind of services anytime, anywhere Affordable cost and one billing The following are some possible features of the 4G systems : Support interactive multimedia, voice, video, wireless internet and other broadband services. High speed, high capacity and low cost per bit. Global mobility, service portability, scalable mobile networks. Seamless switching, variety of services based on Quality of Service (QoS) requirements Better scheduling and call admission control techniques. Ad hoc networks and multi-hop networks Pre-4G Wireless Standards: • WiMAX - 7.2 million units by 2010 (May include fixed and mobile) • Flash-OFDM - 13 million subscribers in 2010 (only Mobile) • 3GPP Long Term Evolution of UMTS in 3GPP - valued at US$2 billion in 2010 (~30% of the world population) • UMB in 3GPP2
28-02-2011, 04:09 PM
FOURTH GENERATION.pptx (Size: 1.27 MB / Downloads: 151) FOURTH GENERATION 4G What is 4G ? 4G = fourth genration / B3G -Beyond 3rd Generation (UMTS, IMT-2000) mobile communications 4G = successor of the 3G and 2G standards 4G - Next level of evolution in the field of wireless communications. 4G -MAGIC –Mobile multimedia , Anytime/anywhere Global mobility support,Integrated wireless and customised personal service. 4G provides fast access. Features 4G will have all standards from 2G and 3G implemented. Infrastructure will be packet-based(all-IP) Open internet platform. Technologies include Flash-OFDM,the 802.16e mobile version of Wimax and HC-SDMA. Higher speed. Objectives A spectrally efficient system(in bits/s/Hz and bits/ s/Hz/site). High network capacity:more simultaneous users per cell A data rate of atleast 100 Mbits/s between any two points in the world. Smooth hand off across heterogeneous networks. Seamless connectivity and global roaming across multiple networks. High quality of service for next generation multimedia support. Interoperability with existing wireless standards. An all IP,packet switched network. Killer” Applications of 4G Location application Visualized virtual navigation Telegeoprocessing: GIS, GPS Life- saving: Telemedicine Voice over Internet Protocol (VoIP) for IPv6 Crisis management applications 4G uses : Smart antennas. Multiple-Input-Multiple-Output (MIMO)systems. Space-time coding. Dynamic Packet Assignment. Wideband OFDM.
01-03-2011, 04:29 PM
4G TEHNOLOGY-A SENSATION.doc (Size: 160 KB / Downloads: 114) 4G TEHNOLOGY Abstract This paper describes an architecture for differentiation of Quality of Service in heterogeneous wireless-wired networks. This architecture applies an “all-IP” paradigm, with embedded mobility of users. The architecture allows for multiple types of access networks, and enables user roaming between different operator domains. The overall 4G architecture discussed in this paper is IPv6-based, supporting seamless mobility between different access technologies. Mobility is a substantial problem in such environment, because inter-technology handovers have to be supported. In our case, we targeted Ethernet (802.3) for wired access; Wi-Fi (802.11b) for wireless LAN access; and W-CDMA - the radio interface of UMTS - for cellular access.The architecture is able to provide quality of service per-user and per-service An integrated service and resource management approach is presented based on the cooperative association between Quality of Service Brokers and Authentication, Authorisation, Accounting and Charging systems. The different phases of QoS-operation are discussed. The overall QoS concepts are presented with some relevant enhancements that address specifically voice services. In particular, EF simulations results are discussed in this context. 1:INTRODUCTION 1.1 WIRELESS COMMUNICATION: A wireless network is an infrastructure for communication “through the air”, in other words, no cables are needed to connect from one point to another. These connections can be used for speech, e-mail, surfing on the Web and transmission of audio and video. The most widespread use is mobile telephones. Wireless networks are also used for communication between computers. This note focuses on ways to set up wireless connections between computers. It gives a basic overview without becoming too technical. It will help to determine whether a wireless network might be a suitable solution. It also is a guide to more resources. Many links are to a document by Mike Jensen. The links used are examples; they are not preferred products. 1.2 GENERATIONS OF WIRELESS COMMUNICATION: 1G: These first generation mobile systems were designed to offer a single service that is speech. 2G: These second generation mobile systems were also designed primarily to offer speech with a limited capability to offer data at low rates. 3G: These third generation mobile systems are expected to offer high quality multimedia services and operative different environments. These systems are referred to as universal mobile telecommunication systems (UMTS) in Europe and international mobile telecommunication systems 2000(IMT2000) worldwide. 4G: This is user-driven, user controlled services and context aware applications. Compared to 3G ,4G has higher data rates and it has QOS which is the main criteria in 4G wireless commuication. Availability of the network services anywhere, at anytime, can be one of the key factors that attract individuals and institutions to the new network infrastructures, stimulate the development of telecommunications, and propel economies. This bold idea has already made its way into the telecommunication community bringing new requirements for network design, and envisioning a change of the current model of providing services to customers. The emerging new communications paradigm assumes a user to be able to access services independently of her or his location, in an almost transparent way, with the terminal being able to pick the preferred access technology at current location (ad-hoc, wired, wireless LAN, or cellular), and move between technologies seamlessly i.e. without noticeable disruption. Unified, secure, multi-service, and multiple-operator network architectures are now being developed in a context commonly referenced to as networks Beyond-3G or, alternatively, 4G networks . 2 AN ALL-IP 4G NETWORK ARCHITECTURE: The overall 4G architecture discussed in this paper is IPv6-based, supporting seamless mobility between different access technologies. Mobility is a substantial problem in such environment, because inter-technology handovers have to be supported. In our case, we targeted Ethernet (802.3) for wired access; Wi-Fi (802.11b) for wireless LAN access; and W-CDMA - the radio interface of UMTS - for cellular access (Fig. 1). With this diversity, mobility cannot be simply handled by the lower layers, but needs to be implemented at the network layer. An "IPv6-based" mechanism has to be used for interworking, and no technology-internal mechanisms for handover, neither on the wireless LAN nor on other technology, can be used. So, in fact no mobility mechanisms are supported in the W-CDMA cells, but instead the same IP protocol supports the movement between cells. Similarly, the 802.11 nodes are only in BSS modes, and will
05-03-2011, 04:22 PM
4G.ppt (Size: 2.09 MB / Downloads: 103) 4G What is fourth generation (4G) mobile systems? Fourth generation mobile communications systems that are characterised by high-speed data rates at 20 to 100 Mbps, suitable for high-resolution movies and television, virtual . Initial deployments are anticipated in 2006-2010. 4G: Anytime, Anywhere Connection Also known as ‘Mobile Broadband everywhere’ MAGIC Mobile Multimedia Communication Anywhere, Anytime with Anyone Global Mobility Support Integrated Wireless Solution Customized Personal Service According to 4G Mobile Forum, by 2008 over $400 billion would be invested in 4G mobile projects. In India, communication Minister Mr. Dayanidhi Maran, has announced a national centre of excellence to work in 4G arena. 4G: Data rate Facts Transmission at 20 Mbps 2000 times faster than mobile data rates 10 times faster than top transmission rates planned in final build out of 3G broadband mobile 10-20 times faster than standard ADSL services. Companies developing 4G technology Cellular phone companies: Alcatel, Nortel, Motorola, IT Companies: Hughes,HP,LG Electronics KEY TECHNOLOGY WIMAX : WORLDWIDE INTEROPERABILITY FOR MICROWAVE ACESS WIMAX IS BASSED ON OFDMA TECHNOLOGY OFDMA : ORTHOGONAL FREQUENCY DIVISION MULTIPLE ACESS 1 MILE MOBILE BROADBAND ACESS ALTERNATIVE TO CABLE OR DSL MODEM. IEEE802.16 a AND IEEE802.20 ARE THE WIMAX STANDARDS . WIBRO : WIRELESS BRADBAND WIBRO IS A KOREAN TECHNOLOGY 8.75 MHZ CHANNEL BANDWIDTH AROUND 30 MILES (50KM) IN FIXED STATION AND 3-10 MILES(15KM) FOR MOBILE STATION BROADBAND ACESS . IEEE 802.16 e AND IEEE802.22 ARE THE WIBRO STANDARDS .
05-03-2011, 08:19 PM
PLEASE SEND THE FULL REPORT
06-03-2011, 10:10 AM
Hey,
go through all the pages of the thread. more than one report and ppt of the topic have been posted here.
07-03-2011, 02:35 PM
4g seminarSB.docx (Size: 915.53 KB / Downloads: 102) 1 Introduction Consumers demand more from their technology. Whether it be a television, cellular phone, or refrigerator, the latest technology purchase must have new features. With the advent of the Internet, the most-wanted feature is better, faster access to information. Cellular subscribers pay extra on top of their basic bills for such features as instant messaging, stock quotes, and even Internet access right on their phones. But that is far from the limit of features; manufacturers entice customers to buy new phones with photo and even video capability. It is no longer a quantum leap to envision a time when access to all necessary information — the power of a personal computer — sits in the palm of one’s hand. To support such a powerful system, we need pervasive, high-speed wireless connectivity. A number of technologies currently exist to provide users with high-speed digital wireless connectivity; Bluetooth and 802.11 are examples. These two standards provide very high-speed network connections over short distances, typically in the tens of meters. Meanwhile, cellular providers seek to increase speed on their long-range wireless networks. The goal is the same: long-range, high-speed wireless, which for the purposes of this report will be called 4G, for fourth-generation wireless system. Such a system does not yet exist, nor will it exist in today’s market without standardization. Fourth-generation wireless needs to be standardized throughout the United States due to its enticing advantages to both users and providers. 2 Economic Impact 2.1 Advantages of 4G In a fourth-generation wireless system, cellular providers have the opportunity to offer data access to a wide variety of devices. The cellular network would become a data network on which cellular phones could operate — as well as any other data device. Sending data over the cell phone network is a lucrative business. In the information age, access to data is the “killer app” that drives the market. The most telling example is growth of the Internet over the last 10 years. Wireless networks provide a unique twist to this product: mobility. This concept is already beginning a revolution in wireless networking, with instant access to the Internet from anywhere. 2.2 Problems with the Current System One may then wonder why ubiquitous, high-speed wireless is not already available. After all, wireless providers are already moving in the direction of expanding the bandwidth of their cellular networks. Almost all of the major cell phone networks already provide data services beyond that offered in standard cell phones, as illustrated in Table 1. Unfortunately, the current cellular network does not have the available bandwidth nec-essary to handle data services well. Not only is data transfer slow — at the speed of analog modems — but the bandwidth that is available is not allocated effeciently for data. Data transfer tends to come in bursts rather than in the constant stream of voice data. Cellular providers are continuing to upgrade their networks in order to meet this higher demand by switching to different protocols that allow for faster access speeds and more effecient transfers. These are collectively referred to as third generation, or 3G, services. However, the way in which the companies are developing their networks is problematic — all are currently proceeding in different directions with their technology improvements. Figure 1 illustrates the different technologies that are currently in use, and which technologies the providers plan to use. Although most technologies are similar, they are not all using the same protocol. In addition, 3G systems still have inherent flaws. They are not well-designed for data; they are improvements on a protocol that was originally designed for voice. Thus, they are in effecient with their use of the available spectrum bandwidth. A data-centered protocol is needed.
08-03-2011, 10:00 AM
Fourth generation wireless system is a packet switched wireless system with wide area coverage and high throughput. It is designed to be cost effective and to provide high spectral efficiency . The 4g wireless uses Orthogonal Frequency Division Multiplexing (OFDM), Ultra Wide Radio Band (UWB),and Millimeter wireless. Data rate of 20mbps is employed. Mobile speed will be up to 200km/hr.The high performance is achieved by the use of long term channel prediction, in both time and frequency, scheduling among users and smart antennas combined with adaptive modulation and power control. Frequency band is 2-8 GHz. it gives the ability for world wide roaming to access cell anywhere.
Wireless mobile communications systems are uniquely identified by "generation designations. Introduced in the early 1980s, first generation (1G) systems were marked by analog frequency modulation and used primarily for voice communications. Second generation (2G) wireless communications systems, which made their appearance in the late 1980s, were also used mainly for voice transmission and reception The wireless system in widespread use today goes by the name of 2.5G-an "in between " service that serves as a stepping stone to 3G. Whereby 2G communications is generally associated with Global System for Mobile (GSM) service, 2.5G is usually identified as being "fueled " by General Packet Radio Services (GPRS) along with GSM. In 3G systems, making their appearance in late 2002 and in 2003, are designed for voice and paging services, as well as interactive media use such as teleconferencing, Internet access, and other services. The problem with 3G wireless systems is bandwidth-these systems provide only WAN coverage ranging from 144 kbps (for vehicle mobility applications) to 2 Mbps (for indoor static applications). Segue to 4G, the "next dimension " of wireless communication. The 4g wireless uses Orthogonal Frequency Division Multiplexing (OFDM), Ultra Wide Radio Band (UWB), and Millimeter wireless and smart antenna. Data rate of 20mbps is employed. Mobile speed will be up to 200km/hr.Frequency band is 2 ]8 GHz. it gives the ability for world wide roaming to access cell anywhere. As the virtual centre of excellence in mobile and personal communications (Mobile VCE) moves into its second core research programme it has been decided to set up a fourth generation (4G) visions group aimed at harmonising the research work across the work areas and amongst the numerous researchers working on the programme. This paper outlines the initial work of the group and provides a start to what will become an evolving vision of 4G. A short history of previous generations of mobile communications systems and a discussion of the limitations of third generation (3G) systems are followed by a vision of 4G for 2010 based on five elements: fully converged services, ubiquitous mobile access, diverse user devices, autonomous networks and software dependency. This vision is developed in more detail from a technology viewpoint into the key areas of networks and services, software systems and wireless access. The major driver to change in the mobile area in the last ten years has been the massive enabling implications of digital technology, both in digital signal processing and in service provision. The equivalent driver now, and in the next five years, will be the all pervasiveness of software in both networks and terminals. The digital revolution is well underway and we stand at the doorway to the software revolution. Accompanying these changes are societal developments involving the extensions in the use of mobiles. Starting out from speech-dominated services we are now experiencing massive growth in applications involving SMS (Short Message Service) together with the start of Internet applications using WAP (Wireless Application Protocol) and i-mode. The mobile phone has not only followed the watch, the calculator and the organiser as an essential personal accessory but has subsumed all of them. With the new Internet extensions it will also lead to a convergence of the PC, hi-fl and television and provide mobility to facilities previously only available on one network.
08-03-2011, 12:34 PM
bhuwan.pptx (Size: 540.37 KB / Downloads: 72) 4G The fourth generation of Cellular Wireless Standards Overview • A 4G system is expected to provide a comprehensive and secure all-IP based solution where facilities such as IP telephony, ultra-broadband Internet access, gaming services and streamed multimedia may be provided to users. • An IMT-Advanced cellular system must have target peak data rates of up to approximately 100 Mbit/s for high mobility such as mobile access and up to approximately 1 Gbit/s for low mobility such as nomadic/local wireless access, according to the ITU requirements. Scalable bandwidths up to at least 40 MHz should be provided.[5][6] Predecessors of 4G • 2G • 3G 2G • 2G technologies can be divided into TDMA-based and CDMA-based standards depending on the type of multiplexing used • FDMA TDMA • CDMA • A new dimension is added. • This is code. 3G • better known as 3G or 3rd Generation, is a generation of standards for mobile phones and mobile telecommunications services fulfilling specifications by the International Telecommunication Union.[1] Application services include wide-area wireless voice telephone, mobile Internet access, video calls and mobile TV, all in a mobile environment. Compared to the older 2G and 2.5G standards, a 3G system must allow simultaneous use of speech and data services, and provide peak data rates of at least 200 kbit/s according to the IMT-2000 specification. Disadvantages of 2G • The downsides of 2G systems, not often well publicized, are: • In less populous areas, the weaker digital signal may not be sufficient to reach a cell tower. • Analog has a smooth decay curve, digital a jagged steppy one. This can be both an advantage and a disadvantage. Under good conditions, digital will sound better. Under slightly worse conditions, analog will experience static, while digital has occasional dropouts. • While digital calls tend to be free of static and background noise, the lossy compression used by the codecs takes a toll; the range of sound that they convey is reduced.
09-03-2011, 09:18 AM
4g FINAL.doc (Size: 48.7 KB / Downloads: 67) 1. INTRODUCTION 4G (short for 4th Generation Communication Systems) represents the future of mobile communications in the longer term. Currently we are using and experiencing mainly 2G (2nd Generation) technology. To be accurate, we are at a stage when 2G is giving way to the succeeding generations – 2.5G (enhancements on 2G) and 3G (3rd Generation) technologies. While 2.5G has been available for the past couple of years 3G is only just beginning to be rolled out in many countries. It was deployed on a worldwide scale by early this year. With each generation a gradual evolution and improvement of technology has occurred. The standardization process has also become more streamlined with each generation. 2. WHY 4G? This raises the question, if 3G is not quite established yet, why are we talking about 4G? The answer is that if research and planning into 4G is not carried out now, it will not be possible to keep up with consumer demand. While 3G will attempt to satisfy demand in the current and short-term future, the market will outgrow 3G in a matter of years. The importance of planning ahead to 4G is also highlighted by the fact that 3G systems are not cross compatible or unified on a worldwide scale and may not live up to all the hype. With mobile communications, the evolutionary pattern seems to follow 1-decade cycles. In the 80’s it was 1G, in the 90’s 2G and now in the new century 3G systems are being introduced. Thus it seems logical that 4G will be introduced around the 2010 mark. In the US, in the period between 1994 and 2001 mobile phone subscriber ship increased from 16 million to 110 million. Such trends have been witnessed in most developed and various developing nations. In Japan, the ‘I mode’ mobile Internet service already had approximately 17 million subscribers by the end of 2000. The statistics and trends indicate that while the number if subscribers to mobile services increase steadily, the requirements of a mobile communication system will also change. In the past the mobile phone has been used mainly for voice application and person-to-person contract. In the future the demand will shift towards data and multimedia services rather than voice. According to estimates, in 2005, of the 1.6 billion Internet users worldwide, 1 billion will be mobile Internet users, and by 2015 mobile traffic is expected to grow to 23-fold that of today, with 90% being multimedia. 3. WHAT IS 4G? 4G is an attempt to evolve, integrate and amalgamate the current 2G (2nd Generation), the soon to be released 3G (3rd Generation), broadcast, WLAN (wireless Local Area Network), short-range and fixed wire systems into a single, fully functional, seamless Internet work. 4G is NOT a complete overhaul of all old technology. It involves a mix of current concepts and technologies in the making. Some of these are derived from 3G and hence are evolutionary, while others are totally new concepts and can be thought of as revolutionary. 4G will features a scalable, flexible, efficient, autonomous, secure and feature-rich backbone to support a multitude of existing and new services and to interface with many different types of networks. It will offer fully converged services (voice, data, and multimedia) at data rates of up to 100 Mbps and ubiquitous mobile access to a vast array of user devices autonomous networks 4. CHARACTERISTICS OF 4G: Fully Converged Services: A wide range of services will be available to the mobile user conveniently and securely via the 4G Core Network. Personal Communications, information systems and entertainment will seem to be merged into a seamless pool of content. Ubiquitous Mobile Access: 4G aims to provide access to multimedia services anytime anywhere. Devices will not simply rely on cellular reception. Improved radio access technology as well as integration of all types of communication networks allows fir virtually constant connectivity to the 4G-core backbone. Mobile handsets will be intelligent and software-reconfigurable on the fly to allow them to interface with different types of networks on the move. Also, there will be full cross compatibility on a worldwide scale since each type of networks has a gateway to the IP backbone. Software Dependency: Advanced software systems are employed for all purposes-network operation, service provision, interfacing and integration, etc. Not only the Core Network but also the mobile devices will be highly intelligent as well as reconfigurable via software. Diverse User Devices: A defining feature of 4G will be the proliferation of a vast array of devices that are capable of accessing the 4G backbones. Wireless capabilities will be embedded into devices that we wouldn’t even consider today. Not only personal devices that we wouldn’t even consider today. Not only personal devices like phones, PDAs, laptops, etc. but also sensors, embedded controllers and other specialized equipment. The point behind this is to allow them to autonomously communicate with each other. By building in sophisticated software, they will be able to automatically initiate timely actions. 2G enabled mobile person-to-person communications while 3G is opening the door to person-to-machine communication with mobile Internet. 4G introduces another dimension with machine-to-machine communication. Autonomous Networks: While user devices are highly intelligent, the core network will also be very sophisticated. It will be capable of managing itself and dynamically adapting to changing network conditions and user preferences for seamless communication. Apart from evolved mobility management, connection control, hand-over mechanisms, etc. dynamic bandwidth allocation will make far more efficient use of the available radio spectrum. 4G Services: 4G data rates will between a few Mbps and 100 Mbps, hence the level oif services that can be offered is quite tremendous. Apart from 3G services like World Wide Web, Email, and wireless E-commerce this data rate is quite adequate to support the high Qos become on-demand infotainment services. Video-conferencing services will be of high quality and almost as good as meeting in person. Ad Hoc networking (dynamic formation of wireless networks between wireless devices without any central infrastructure or administration) will allow for Personal Area Networks, in-house networks and the like, which allow wireless devices to perform various activities autonomously. Alarm notification, sensor data acquisition and remote control of home appliances are some of the possibilities. It is more than likely that mobile services that have not even been envisaged will exist in 4G.
09-03-2011, 12:40 PM
4g wireless technology.doc (Size: 297.5 KB / Downloads: 51) Introduction Pick up any newspaper today and it is a safe bet that you will find an article somewhere relating to mobile communications. If it is not in the technology section it will almost certainly be in the business section and relate to the increasing share prices of operators or equipment manufacturers, or acquisitions and take-overs thereof. Such is the pervasiveness of mobile communications that it is affecting virtually everyone’s life and has become a major political topic and a significant contributor to national gross domestic product (GDP). The major driver to change in the mobile area in the last ten years has been the massive enabling implications of digital technology, both in digital signal processing and in service provision. The equivalent driver now, and in the next five years, will be the all pervasiveness of software in both networks and terminals. The digital revolution is well underway and we stand at the doorway to the software revolution. Accompanying these changes are societal developments involving the extensions in the use of mobiles. Starting out from speech-dominated services we are now experiencing massive growth in applications involving SMS (Short Message Service) together with the start of Internet applications using WAP (Wireless Application Protocol) and i-mode. The mobile phone has not only followed the watch, the calculator and the organiser as an essential personal accessory but has subsumed all of them. With the new Internet extensions it will also lead to a convergence of the PC, hi-fl and television and provide mobility to facilities previously only available on one network. The development from first generation analogue systems (1985) to second generation (2G) digital GSM (1992) was the heart of the digital revolution. But much more than this it was a huge success for standardisation emanating from Europe and gradually spreading globally. However, world-wide roaming still presents some problems with pockets of US standards IS-95 (a code division multiple access [CDMA] rather than a time division multiple access [TDMA] digital system) and IS- 136 (a TDMA variant) still entrenched in some countries. Extensions to GSM (2G) via GPRS (General Packet Radio Service) and EDGE (Enhanced Data rates for GSM Evolution) (E-GPRS) as well as WAP and i-mode (so called 2.5G) will allow the transmission of higher data rates as well as speech prior to the introduction of 3G. Mobile systems comprise a radio access together with a supporting core network. In GSM the latter is characterised by MAP (Mobile Applications Protocol), which provides the mobility management features of the system. GSM was designed for digital speech services or for low bit rate data that could fit into a speech channel (e.g. 9.6kbit/s). It is a circuit rather than a packet oriented network and hence is inefficient for data communications. To address the rapid popularity increase of Internet services, GPRS is being added to GSM to allow packet (Internet Protocol [IP]) communications at up to about 100kbit/s. Third generation (3G) systems were standardised in 1999. These include IMT-2000 (International Mobile Telecommunications 2000), which was standardised within ITU-R and includes the UMTS (Universal Mobile Telecommunications System) European standard from ETSI (European Telecommunications Standards Institute), the US derived CDMA 2000 and the Japanese NTT DoCoMo W-CDMA (Wideband Code Division Multiple Access) system. Such systems extend services to (multirate) high-quality multimedia and to convergent networks of fixed, cellular and satellite components. The radio air interface standards are based upon W-CDMA (UTRA FDD and UTRA TDD in UMTS, multicarrier CDMA 2000 and single carrier UWC-136 on derived US standards). The core network has not been standardised, but a group of three—evolved GSM (MAP), evolved ANSI-41 (from the American National Standards Institute) and IP-based— are all candidates. 3G is also about a diversity of terminal types, including many non-voice terminals, such as those embedded in all sorts of consumer products. Bluetooth (another standard not within the 3G orbit, but likely to be associated with it) is a short-range system that addresses such applications. Thus services from a few bits per second up to 2Mbit/s can be envisioned. For broadband indoor wireless communications, standards such as HIPERLAN 2 (High Performance Local Area Network—ETSI’s broadband radio access network [BRAN]) and IEEE 802.lla have emerged to support IP based services and provide some QoS (quality of service) support. Such systems are based on orthogonal frequency division multiplexing (OFDM) rather than CDMA and are planned to operate in the 5GHz band. Whereas 2G operates in 900 and 1800/1900MHz frequency bands, 3G is intended to operate in wider bandwidth allocations at 2GHz. These new frequency bands will provide wider bandwidths for some multimedia services and the first allocations have been made in some countries via spectrum auctions (e.g. in the UK, Holland and Germany) or beauty contests (in France and Italy). The opportunity has also been taken to increase competition by allowing new operators into the bands as well as extending existing operator licences. These new systems will comprise microcells as well as macrocells in order to deliver the higher capacity services efficiently. 3G and 2G will continue to coexist for some time with optimisation of service provision between them. Various modes of delivery will be used to improve coverage in urban, suburban and rural areas, with satellite (and possibly HAPS—high altitude platform stations) playing a role. |
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