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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.

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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

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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 .

PLEASE SEND THE FULL REPORT

Hey,
go through all the pages of the thread. more than one report and ppt of the topic have been posted here.

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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.

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.

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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.

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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.

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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.

wirelessccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccc

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ABSTRACT:- 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 wireless access 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, and applications 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.
DEFINITION:-4G is the short term for fourth-generation wireless, the stage of broadband mobile communications that will supercede the third generation (3G). it is expected that end-to-end IP and high-quality streaming video will be among 4G's distinguishing features. Fourth generation networks are likely to use a combination of WiMAX and WiFi. 4G technologies are sometimes referred to by the acronym "MAGIC," which stands for Mobile multimedia, Anytime/any-where, Global mobility support, Integrated wireless and Customized personal service.
Although 3G networks were really about the technology, 4G networks are both a technology and a business transformation.
4G will potentially reshape not just the wireless industry, but also cable, wireline and handset companies. It will also simultaneously provide the media and entertainment industries another avenue for content delivery.
4G HISTORY:-
At the end of the 1940’s, the first radio telephone service was introduced, and was designed to users in cars to the public land-line based telephone network. Then, in the 60s, a system launched by Bell Systems, called IMTS, or, “Improved Mobile Telephone Service", brought quite a few improvements such as direct dialling and more bandwidth. The very first analog systems were based upon IMTS and were created in the late 60s and early 70s. The systems were called "cellular" because large coverage areas were split into smaller areas or "cells", each cell is served by a low power transmitter and receiver.
The 1G, or First Generation. 1G was an analog system, and was developed in the 70s, 1G had two major improvements, this was the invention of the microprocessor, and the digital transform of the control page link between the phone and the cell site.
1G analog system for mobile communications saw two key improvements during the 1970s: the invention of the microprocessor and the digitization of the control page link between the mobilephone and the cell site.
Advance mobile phone system (AMPS) was first launched by the US and is a 1G mobile system. Based on FDMA, it allows users to make voice calls in 1 country
2G, OR SECOND GENERATION:
2G first appeared around the end of the 1980’s, the 2G system digitized the voice signal, as well as the control link. This new digital system gave a lot better quality and much more capacity (i.e. more people could use there phones at the same time), all at a lower cost to the end consumer. Based on TDMA, the first commercial network for use by the public was the Global system for mobile communication (GSM).
3G, or THIRD GENERATION:-
3G systems promise faster communications services, entailing voice, fax and Internet data transfer capabilities, the aim of 3G is to provide these services any time, anywhere throughout the globe, with seamless roaming between standards. ITU’s IMT-2000 is a global standard for 3G and has opened new doors to enabling innovative services and application for instance, multimedia entertainment, and location-based services, as well as a whole lot more. In 2001, Japan saw the first 3G network launched.
3G technology supports around 144 Kbps, with high speed movement, i.e. in a vehicle. 384 Kbps locally, and up to 2Mbps for fixed stations, i.e. in a building.
4G, or FOURTH GENERATION:-
For 1 and 2G standards, bandwidth maximum is 9.6 kbit/sec, This is approximately 6 times slower than an ISDN (Integrated services digital network). Rates did increase by a factor of 3 with newer handsets to 28.8kbps. This is rarely the speed though, as in crowded areas, when the network is busy, rates do drop dramatically.
Third generation mobile, data rates are 384 kbps (download) maximum, typically around 200kbps, and 64kbps upload. These are comparable to home broadband connections.
Fourth generation mobile communications will have higher data transmission rates than 3G. 4G mobile data transmission rates are planned to be up to 100 megabits per second on the move and 1000gigbits per second stationary, this is a phenomenal amount of bandwidth, only comparable to the bandwidth workstations get connected directly to a LAN.
Motivation for 4G Research Before 3G Has Not Been Deployed?
• 3G performance may not be sufficient to meet needs of future high-performance applications like multi-media, full-motion video, wireless teleconferencing. We need a network technology that extends 3G capacity by an order of magnitude.
• There are multiple standards for 3G making it difficult to roam and interoperate across networks. we need global mobility and service portability
• 3G is based on primarily a wide-area concept. We need hybrid networks that utilize both wireless LAN (hot spot) concept and cell or base-station wide area network design.
• We need wider bandwidth
• Researchers have come up with spectrally more efficient modulation schemes that can not be retrofitted into 3G infrastructure
• We need all digital packet network that utilizes IP in its fullest form with converged voice and data capability.

Submitted by:
Himanshu Pareek

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4G Technology
Introduction:
4G stands for the fourth generation of cellular wireless standards. It is a successor to 3G and 2G families of standards. Speed requirements for 4G service set the peak download speed at 100 Mbit/s for high mobility communication (such as from trains and cars) and 1 Gbit/s for low mobility communication (such as pedestrians and stationary users).
A 4G system is expected to provide a comprehensive and secure all-IP based mobile broadband solution to smart phones, laptop computer wireless modems and other mobile devices. Facilities such as ultra-broadband Internet access, IP telephony, gaming services, and streamed multimedia may be provided to users. The technologies that fall in the 4G categories are UMTS, OFDM, SDR, TD-SCDMA, MIMO and WiMAX to the some extent.
4G Technology offers high data rates that will generate new trends for the market and prospects for established as well as for new telecommunication businesses. 4G networks, when tied together with mobile phones with in-built higher resolution digital cameras and also High Definition capabilities will facilitate video blogs.
Some key features (primarily from users' points of view) of 4G mobile networks are as follows:
 High usability: anytime, anywhere, and with any technology
 Support for multimedia services at low transmission cost
 Personalization
 Integrated services
 open Internet platform

Presented by:
Pravin Rasal

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Introduction
• 4G usually refers to the successor of the 3G and 2G standards.
• 4G is a broader term and could include standards outside IMT-Advanced.
• A 4G system may upgrade existing communication networks and is expected to provide a secure IP based solution where facilities such as voice, data and streamed multimedia will be provided to users on an "Anytime, Anywhere" basis and at much higher data rates compared to previous generations.
What is 4G ?
 4G, fourth-generation, is a technology that will transform wireless communications in a completely new way.
 It is also known as “beyond 3G,"
 It is also known as “beyond 3G," since it provides a secure IP (Internet Protocol) solution.
History of 4G
• At the end of the 1940’s, the first radio telephone service was introduced, and was designed to users in cars to the public land-line based telephone network.
• Then, in the sixties, a system launched by Bell Systems, called IMTS, or, “Improved Mobile Telephone Service", brought quite a few improvements such as direct dialling and more bandwidth.

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Presentated by:
A.HARIHARAN
P.THIRUVADISAMY

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ABSTRACT to the third generation of mobile telephony (that is, cellular) technology. The third generation, as the name suggests, follows two earlier s.
Evolution of Mobile Network
First generation (1G): Analog voice systems
Second Generation (2G): Digital voice systems
Second Generation – advanced (2.5G): Combining voice and data communications
Third Generation (3G): Digital voice and data communications
– Developing a more general mobile network
• Handling Internet access, email, messaging, multimedia
• Access to any services (voice, video, data, etc.)
– Requires high quality transmission
Fourth Generation (4G): All-IP mobile networks
– Ubiquitous wireless communications
– Transparent to any services
– Integrating multi-networks
• IG 2G

• 3G 4G
4G NETWORK ARCHITECTURE
- The number of access networks in public, private business and home areas is increasing.
- Service providers will need access to specific network characteristics to be able to enhance their services, and may have certain requirements such as minimum delay guarantees.
- Another aspect is that the user needs to control the usage of the available networks, especially when this usage comes with a price.
• HOW 4G WORKS
- 4G is being developed to accommodate the quality of service (QoS).
- Objectives:
* A spectrally efficient
* High network capacity
* Data rate:
100 Mbit/s between any two points in the world
* Smooth handoff
* Seamless connectivity
* High quality of service for next generation
* Interoperability with existing wireless standards
* Packet switched network.
4G SYSTEM
- It should dynamically share and utilize network resources to meet the minimal requirements.
- Stands for fourth generation of cellular wireless standard.
- Successor to 3G and 2G families.
- Download speed:
high mobility communication:100 Mbit/s
low mobility communication:1 Gbit/s
- Provide a comprehensive and secure all-IP based mobile broadband solution.
FEATURES OF 4G
Spontaneous self organization of networks of devices.
Not necessarily connected to internet.
4G will create hybrid wireless networks using Ad Hoc networks.
Form of mesh networking–Very reliable.
• 4G HARDWARE
• Ultra Wide Band Networks
• Smart Antennas
• 4G SOFTWARE
• Software Defined Radio
• Interactive media Plat-form
4G HARDWARE
Ultra Wide Band Networks:
- Advanced transmission technology.
- Used in implementation of 4G.
- It is typically detected as noise.
- Noise does not cause interference with current radio frequency devices.
- But it can reassemble the noise back into a signal.
- Works by emitting a series of short, low powered electrical pulses.
- The pulse can be called “shaped noise” because it is not flat, but curves across the spectrum.
- Frequency : between 3.1 to 10.6 GHz.
- Bandwidth : 60 megabits per second.
Smart Antennas:
- Multiple “smart antennas” can be employed to help find, tune, and turn up signal information.
- The antennas can both “listen” and “talk”.
- A smart antenna can send signals backing the same direction that they came from.
- Two Types:
Switched Beam Antennas
Adaptive Array Antennas
Uses:
• Optimize available power
• Increase base station range and coverage
• Reuse available spectrum
• Increase bandwidth
• Lengthen battery life of wireless devices
Switched Beam Antennas:
- It have fixed beams of transmission.
- It can switch from one predefined beam to another when the user with the phone moves throughout the sector.
Adaptive Array Antenna:
- It is needed to process data on both the sending and receiving side.
- This software should be flexible, as the future wireless world will likely be a heterogeneous mix of technologies.
- Minimize interference.
- Maximize intended signal reception.
• Smart Antennas
4G SOFTWARE
- 4G needs to support a wide range of mobile devices .
- These devices would have to support different networks.
- Solution : “software defined radio”.
Software Defined Radio:
- It can be configured to any radio or frequency standard through the use of software.
- Advantages:
Flexibility for wireless standards. Dynamically updated with new software
Roaming is not an issue.
- In order to be able to download software at any location, the data must be formatted to some standard.
- This is the job of the packet layer, which will split the data into small “packets.”
Interactive media Plat-form:
- Software platform for mobilestreaming applications.
- Designed as an end-to-end solution, the system consists of ,
Dedicated content creation machines.
Player application runs on widely used operating systems.
Content servers hold newly created multimedia content.
Proxy builds interface between the player application and other platform.
WIMAX
 Worldwide Inter operability for Microwave Access.
"mobile WiMAX", "802.16d" and "802.16e" are frequently used incorrectly.
Correct definitions are the following:
• 802.16-2004 is often called 802.16d, since that was the working party that developed the standard. It is also frequently referred to as "fixed WiMAX" since it has no support for mobility.
• 802.16e-2005 is an amendment to 802.16-2004 and is often referred to in shortened form as 802.16e. It introduced support for mobility, among other things and is therefore also known as "Mobile WiMAX".
Living 4G in a 3G World
Currently the 4G network is not supporting voice services in its simplest form.
The 4G wireless network works on a different frequency than the 3G wireless network.
Many of the new 4G wireless network phones available now will be a hybrid of both 4G and 3G networks.
The 4G to handle data services and the 3G to handle voice calls.
TRAFFIC CONTROL DURING DISASTER
APPLICATION
 Virtual Navigation
 Tele-Medicine
 Crisis Management Applications
ADVANTAGES
• High usability: anytime, anywhere, and with any technology.
• Support for multimedia services at low transmission cost.
•Higher bandwidth, tight network security.
DISADVANTAGES
• The equipment required to implement a next generation network is still very expensive.
• Carriers and providers have to plan carefully to make sure that expenses are kept realistic.
CONCLUSION
Low cost high speed data will drive forward the fourth generation (4G) as short- range communication emerges.
It is probable that the radio access network will evolve from a centralized architecture to a distributed one.
4G is likely to enable the download of full length songs or music pieces which may change the market response dramatically.
Innovations in network technology will provide an environment in which virtually anything is available, anywhere, at any time, via any connected device.

Abstract
Currently 2G Technology (GSM), or second generation technology, is widely used worldwide for cell phone networks. The problem with 2G technology is that the data rates are limited. This makes it inefficient for data transfer applications such as video conferencing, music or video downloads. To increase the speed, various new technologies have been in development.
One of these, 4G technology, is mainly made up of high-speed wireless networks designed to carry data, rather than voice or a mixture of the two. 4G transfers data to and from mobile devices at broadband speeds – up to100 Mbps moving and 1Gbps while the phone is stationary. In addition to high speeds, the technology is more robust against interference and tapping guaranteeing higher security. This innovative technology functions with the aid of VoIP, IPv6, and Orthogonal frequency division multiplexing (OFDM).
To cater the growing needs of 4G, mobile data communication providers will deploy multiple antennas at transmitters to increase the data rate. Unlike the 3G networks, which are a mix of circuit switched and packet switched networks, 4G will be based on packet switching only (TCP/IP). This will allow low-latency data transmission. Furthermore, the use of IP to transfer information will require IPv6 to facilitate the use of more cell phone devices. During the presentation, an overview of the various generations of mobile device technologies preceding 4G would be followed by technical aspects of 4G and how it functions, as well as the way it can lead to future innovations in cellular and communication technology.

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Welcome to the 4G
The term 4G is used broadly to include several types of broadband wirelessaccess communication systems, not only cellular telephone systems.One of the term used to describe 4G is MAGIC-Mobile multimedia
Anytime anywhere
Global mobility support
Integrated wireless solution &
Customized personal service
The 4th generation of mobile networks will truly turn the current mobilephone networks, in to end to end IP based networks. If 4G is implementedcorrectly, it will truly harmonize global warming.
 Before 1G
0G refers to pre-cellular mobile telephony technology….
The system were called “cellular” because large coverage areas were split intosmaller areas or “cells", each cell is served by a low power transmitter &receiver.
At the end of the 1940’s the first radio telephone service was introduced,&was designed to users in cars to the public land-line based telephoneNetworks
In the sixties, a system launched by Bell systems called IMTS, or “ImprovedMobile Telephone Service", brought quite a few improvements such as directdialing & more bandwidth
1G or First generation
The 1G,or First generation. It was an analogous system & was developed in theseventies.1G had two major improvements, this was the invention of the microprocessor.& the digital transform of the control page link between the phone and the cell site.”AMPS” was first launched by USA & is 1G system. It was based on FDMA used to make voice calls in one country.
2G, or Second generation
2G phones using global system for mobile communication(GSM)were first used in the early 1990s in Europe.GSM provide voice and limited data services, and uses digital modulation for improved audio quality. Digital AMPS,SDMA were some of the 2G systems.
3G,or Third Generation
The 3G technology adds multimedia facilities to 2G phone by allowing audio, video & graphics application.
The idea behind the 3G is to have single network standard instead of the different types used in US, Europe & Asia. Telecommunication systems(UMTS)or IMT 2000,will sustain higher data rates & open to door to many Internet style application.
DRAWBACKS BY GENERATION
 1G
 Poor voice quality
 Poor battery life
 Large phone size
 No security
 Frequent call drops
 Limited capacity & poor handoff reliability
2G
 The GSM is circuit switched, connection oriented technology, were end system are dedicated for the entire call session
 This causes inefficiency in usage of bandwidth & resources. The GSM-enabled system do not support high data rates. They are unable to handle complex data such as video.
3G
 High bandwidth requirement
 High spectrum licensing fees
 Huge capital
 Comparison of 3G with 4G
4G or Fourth generation
Some possible standards of the 4G system are 802.20, WiMax(802.16)
HSPDA, UMTS,TDD UMTS & future version of UMTS & proprietary network form ArryComm Inc., NaviniNetworks, Flarion Technologies, and 4G effort in India, China & Japan
The design is that 4G will be based on OFDM, which is the key enabler of the 4G technology. Other technological aspects of the 4g technology are adaptive processing & smart antennas, both of which will be used in 3G networks & enhance rates when used with OFDM
FEATURES
 Faster & more reliable
100 Mb/s(802.11g wireless=54 Mb/s,3G=2 Mb/s)
 Lower cost than previous generation.
 Multi-standard wireless system
Bluetooth, wired, wireless(802.11x)
 Ad Hoc networking
 IPv6 core
 OFDM used instead of CDMA
Different access technology
FDMA:-It is a method were the spectrum is cut up in to different frequencies & then this chunk given to the users. At one time only one user is assigned to a frequency because of this the frequency is closed, until the call is ended, or it is passed on to another frequency.
TDMA:-It makes use of the whole available spectrum, unlike FDMA. Instead of splitting the slot of frequency. It split them by time, over all of the frequency. Each subscriber is given a time slot as opposed to a frequency therefore many uses can sit on one frequency & have different time slots, because the time slots are switched so rapidly TDMA is used for 2G networks.
CDMA:-Uses the spread spectrum method, the way it works means its highly encrypted, so its was no surprise it was developed & used by the military. Unlike FDMA,CDMA allows the user to sit on all the available frequencies at the same time, & hop between then. Each call is identified by its unique code, hence the term code division.
HOW OFDM WORKS
Orthogonal FDM’s spread spectrum technique spreads the data over a lot of carriers that are spread apart at precise frequencies. This spacing provides the “orthogonality” in this method which prevent the receivers/demodulators from seeing frequencies other than their own specific one.
MIMO
 It 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 symbol 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.
 In principle, MIMO is more efficient when many multiple signals are received.
4G technologies
Smart Antennas
 Beam radio signals directly at a user to follow the user as they move
 Allow the same radio frequency to be used for other users without worry of interference
 Can’t keep up transmission speeds whiole device is moving fast(i.e. in car) only 32Mbps at 62Mph(vs100Mb/s)
 Smart antenna technology
 Seamless handoff between towers/access points
 One transmit antenna, two receive antennas
 Allow connection to two access points at once
IPv6 support
IPv6 support is essential in order to support a large, number of wireless-enabled devices. By increasing the number of IP addresses, IPv6 removes the need for Network Address Translation(NAT), a method of sharing a limited number of addresses among a larger group of devices, although NAT will still be required to communicate with devices that are on existing IPv4 networks.
As of June 2009,version has posted specifications that require any 4g devices on its network to support IPv6
APPLICATION
VIRTUAL PRESENCE 4G system gives mobile users a “virtual presence” (for ex, always on connection to keep people on event)video conferencing
VIRTUAL NAVIGATION a remote database contains the graphical representation of streets, buildings, and physical characteristics of a large metropolis. Blocks of this database are transmitted on rapid sequences to a vehicle.
TELE-GEOPROCESSING queries dependent on location information of several users in addition to temporal aspects have many application e.g. GIS,GPS
The news about 4G
 First step towards the full range of Wimax/4G Applications.
This successful implementation of the OFDM waveform is the first step in military technologies plan to implement the complete IEEE.802.16 family of wireless data application
 The new Wi-Fi gels with 4G
More robust standard for high-speed broadband wireless delivery to laptops and desktops will augment the burgeoning Wi-Fi market beginning in late 2004

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Submitted By
N.UDAY KUMAR NAIDU
K. V. RAMANA REDDY

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ABSTRACT
First generation (1G) wireless telecommunications – the brick-like analog phones that are now collector’s items - introduced the cellular architecture that is still being offered by most wireless companies today. Second generation (2G) wireless supported more users within a cell by using digital technology, which allowed many callers to use the same multiplexed channel. But 2G was still primarily meant for voice communications, not data, except some very low data-rate features, like short messaging service (SMS). So-called 2.5G allowed carriers to increase data rates with a software upgrade at the base transceivers stations (BTS), as long as consumers purchased new phones too. Third generation (3G) wireless offers the promise of greater bandwidth, basically bigger data pipes to users, which will allow them to send and receive more information.
Fourth generation (4G) wireless was originally conceived by the Defense Advanced Research Projects Agency (DARPA). Although experts and policymakers have yet to agree on all the aspects of 4G wireless, two characteristics have emerged as all but certain components of 4G: end-to-end Internet Protocol (IP), and peer-to-peer networking. An all IP network makes sense because consumers will want to use the same data applications they are used to in wired networks. The final definition of “4G” will have to include something as simple as this: if a consumer can do it at home or in the office while wired to the Internet, that consumer must be able to do it wirelessly in a fully mobile environment.
INTRODUCTION
Let’s define “4G” as “wireless ad hoc peer-to-peer networking.” 4G technology is significant because users joining the network add mobile routers to the network infrastructure. Because users carry much of the network with them, network capacity and coverage is dynamically shifted to accommodate changing user patterns. As people congregate and create pockets of high demand, they also create additional routes for each other, thus enabling additional access to network capacity. Users will automatically hop away from congested routes to less congested routes. This permits the network to dynamically and automatically self-balance capacity, and increase network utilization. What may not be obvious is that when user devices act as routers, these devices are actually part of the network infrastructure. So instead of carriers subsidizing the cost of user devices (e.g., handsets, PDAs, of laptop computers), consumers actually subsidize and help deploy the network for the carrier.
With a cellular infrastructure, users contribute nothing to the network. They are just consumers competing for resources. But in wireless ad hoc peer-to-peer networks, users cooperate – rather than compete – for network resources. Thus, as the service gains popularity and the number of users increases, service likewise improves for all users.
There is also the 80/20 rule. With traditional wireless networks, about 80% of the cost is for site acquisition and installation, and just 20% is for the technology. Rising land and labor costs means installation costs tend to rise over time, subjecting the service providers’ business models to some challenging issues in the out years. With wireless peer-to-peer networking, however, about 80% of the cost is the technology and only 20% is the installation. Because technology costs tend to decline over time, a current viable business model should only become more profitable over time. The devices will get cheaper, and service providers will reach economies of scale sooner because they will be able to pass on the infrastructure savings to consumers, which will further increase the rate of penetration.
CURRENT TECHNOLOGY
Most modern cellular phones are based on one of two transmission technologies: time-division multiple access (TDMA) or code-division multiple access (CDMA) . These two technologies are collectively referred to as second-generation, or 2G. Both systems make eavesdropping more difficult by digitally encoding the voice data and compressing it, then splitting up the resulting data into chunks upon transmission
TDMA
TDMA, or Time Division Multiple Access, is a technique for dividing the time domain up into sub-channels for use by multiple devices. Each device gets a single time slot in a procession of devices on the network. During that particular time slot, one device
is allowed to utilize the entire bandwidth of the spectrum, and every other device is in the quiescent state.
The time is divided into frames in which each device on the network gets one timeslot. There are n timeslots in each frame, one each for n devices on the network. In practice, every device gets a timeslot in every frame. This makes the frame setup simpler and more
efficient because there is no time wasted on setting up the order of transmission. This has
the negative side effect of wasting bandwidth and capacity on devices that have nothing to send.
One optimization that makes TDMA much more efficient is the addition of a registration period at the beginning of the frame. During this period, each device indicates how much data it has to send. Through this registration period, devices with nothing to send waste no time by having a timeslot allocated to them, and devices with lots of pending data can have extra time with which to send it. This is called ETDMA (Extended TDMA) and can
increase the efficiency of TDMA to ten times the capacity of the original analog cellular phone network.
The benefit of using TDMA with this optimization for network access comes when data is “bursty.” That means, at an arbitrary time, it is not possible to predict the rate or amount of pending data from a particular host. This type of data is seen often in voice transmission, where the rate of speech, the volume of speech, and the amount of background noise are constantly varying. Thus, for this type of data, very little capacity is wasted by excessive allocation.
CDMA
CDMA, or Code Division Multiple Access, allows every device in a cell to transmit over the entire bandwidth at all times. Each mobile device has a unique and orthogonal code that is used to encode and recover the signal. The mobile phone digitizes the voice data as it is received, and encodes the data with the unique code for that phone. This is accomplished by taking each bit of the signal and multiplying it by all bits in the unique code for the phone. Thus, one data bit is transformed into a sequence of bits of the same length as the code for the mobile phone. This makes it possible to combine with other signals on the same frequency range and still recover the original signal from an arbitrary mobile phone as long as the code for that phone is known. Once encoded, the data is modulated for transmission over the bandwidth allocated for that transmission. A block diagram of the process is shown
By keeping security in mind while designing the new system, the creators of 2G wireless were able to produce a usable system that is still in use today. Unfortunately, 2G technology is beginning to feel its age. Consumers now demand more features, which in turn require higher data rates than 2G can handle. A new system is needed that merges voice and data into the same digital stream, conserving bandwidth to enable fast data access. By using advanced hardware and software at both ends of the transmission, 4G is the answer to this problem.

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