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A Project By: SHUBHAM ROY
On
4G WIRELESS COMMUNICATION
ACKNOWLEDGEMENTI am extremely thankful to Mr. Debashis Chakraborty ,Head of Department,Division of ECE,FIEM for permitting me to undertake this work.
I express my heartfelt gratitude to my respected Seminar guide Mr. Mayur De for his kind and inspiring advise which helped me to understand the subject and its sementic
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significance .He enriched me with valuable suggestions regarding my topic and presentation issues.
I am also very thankful to my dear friends who helped and co-operated with me in conducting the seminar by their active participation.
ABSTRACT:-The modern communication system is aimed to reach the real world one environment from virtual world via connecting resources of one with another through social network system. The communication process is aggravated various infrastructural development to reach in this current level such as 3G and 4G communication system. The user expectation also increased to meet their personal and social applications. The users are try to integrate the personal and socialnetwork technology with real time operations for their personal and business objectives. This paper is provides technological features of an existing 4G communication technology and its architecture to integrate the social networking process.
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In order to satisfy the expectation of the users to have more advanced wireless access even in the mobile environments, research and development efforts for realizing the Fourth Generation (4G) mobile communication system has been discussed. This paper outlines the requirements for the system, technical challenges to be solved, and finally describes the activities related to the standardization of the 4G mobile communication system.
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
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the fixed wireless networks. This article 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. An estimate of 1 billion users by the end of 2013 justifies the study and research for 4G systems. The 4G wireless use Orthogonal Frequency Division Multiplexing (OFDM), Ultra Wide Radio Band (UWB), and smart antenna. Data rate of 20mbps is employed. Mobile speed will be up to 200km/hr. Frequency band is
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2 - 8 GHz. It gives the ability for global roaming to access cell anywhere.
TABLE OF CONTENTS PAGE
CHAPTER1. Welcome to the 4G 12
CHAPTER2. INTRODUCTION 12
CHAPTER3. HISTORY 14
CHAPTER4. What is 4G? 16
CHAPTER5. VISION OF 4G 17
CHAPTER6. Evolution of 4G Technology 21
CHAPTER7. 4G STANDARDS 22
CHAPTER8. DEFINITION OF 4G TECHNOLOGY 22
CHAPTER9. Motivation for 4G Research Before 3G Has Not Been Deployed? 24
CHAPTER10. Wireless System Evolution 25
CHAPTER11. KEY 4G TECHNOLOGIES 26
OFDMA (Orthogonal Frequency Division Multiple Access 26
Implementation of MIMO (multiple inputs, multiple outputs) 27
Smart antenna enhancements 28
SDR (Software-Defined Radio) 29
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CHAPTER12. 4G Technology Features 30
CHAPTER13. 4G MOBILE COMMUNICATIONSYSTEMS
31
CHAPTER14. APPLICATIONS OF 4G 32
CHAPTER14. APPLICATIONS OF 4G 34
CHAPTER15. LIMITATIONS 34
CHAPTER16.What is needed to Build 4G Networks of Future? 35
CHAPTER17. CONCLUSION
36
CHAPTER18. REFERRENCE 38
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LIST OF FIGURES
FIGURE NUMBER FIGURE DESCRIPTIOPN PAGE NUMBER 1.1 History of wireless communication 16
1.2 4G Mobile Communication Visions 19
1.3 Seamless Connections of Networks 20 1.4 TIMELINE OF THE EVALUATION
OF 4G TECHNOLOGY 21
1.5 OFDMA PRINCIPLES 27 1.6 SMART ANTENNA PRINCIPLES 28
1.7 An Ideal Software Radio Receiver 29
1.8 The shift from a vertically integrated to a horizontally layered mobile service environment. 4Gnetwork seamlessly integrate Internet protocol transport with a variety of access networks
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1.9 GLOBAL MARKET OF 4G 37
LIST OF TABLES
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TABLE NO. TITLE PAGE NO. 2.1 Short History of
Mobile Telephone Technologies
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LIST OF ABBREVIATIONS
1xRTT = 2.5G CDMA data service up to 384 kbpsAMPS = advanced mobile phone serviceCDMA = code division multiple accessEDGE = enhanced data for global evolutionFDMA = frequency division multiple accessGPRS = general packet radio systemGSM = global system for mobileNMT = Nordic mobile telephonePDC = personal digital cellularPSTN = public switched telephone network
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TACS = total access communications systemTDMA = time division multiple accessWCDMA = wideband CDMA
Welcome to the 4G : Welcome to the 4G 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. The fourth generation of mobile networks will truly turn the current mobile phone networks, in to end to end IP based networks .If 4G is implemented correctly, it will truly harmonized global roaming.
INTRODUCTION:
While 3G hasn't quite arrived, designers are already thinking about 4G
technology. With it comes challenging RF and baseband design headaches.
Cellular service providers are slowly beginning to deploy third-generation (3G)
cellular services. As access technology increases, voice, video, multimedia, and
broadband data services are becoming integrated into the same network. The
hope once envisioned for 3G as a true broadband service has all but dwindled
away. It is apparent that 3G systems, while maintaining the possible 2-Mbps
data rate in the standard, will realistically achieve 384-kbps rates. To achieve
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the goals of true broadband cellular service, the systems have to make the leap
to a fourth-generation (4G) network.
This is not merely a numbers game. 4G is intended to
provide high speed, high capacity, low cost per bit, IP based services. The goal
is to have data rates up to 20 Mbps, even when used in such scenarios as a
vehicle
traveling 200 kilometres/hour. The move to 4G is complicated by attempts to
standardize on a single 3G protocol. Without a single standard on which to
build, designers face significant additional challenges. A descendant to 2G and
3G aiming to provide the very high data transfer rates. This technology can
provide very speedy wireless internet access to not only stationary users but also
to mobile users.
4G, short for fourth-generation wireless
communication systems, has engaged the attention of wireless operators,
equipment makers (OEMs), investors, and industry watchers around the world.
4G refers to the next generation of wireless technology that promises higher
data rates and expanded multimedia services. Since, at this point, 4G is more of
an aspiration than a standard, there is not an agreement yet on what should
constitute 4G.
Since the ITU is a major force in the standardization
of telecommunications technologies, it’s worth looking at the ITU’s
performance goals for 4G:
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The framework for 4G systems should fuse elements of current cellular
systems with nomadic wireless-access systems and personal-area networks in a
seamless layered architecture that is transparent to the user.
Data rates of 100 Mbps for mobile applications and 1 Gbps for nomadic
applications should be achievable by the year 2010.
Worldwide common spectrum and open, global standardization should be
pursued
Still 4G is not clearly defined or documented
anywhere what are the basic requirements to build 4G wireless technology, like
3G is clearly defined in IMT-2000 (International Mobile Telecommunications
2000). IMT-Advanced is the closest where some of the 4G requirements can be
found. For supporting high data rate and high mobility in fast moving car
(60kilometers/hours) or fast moving trains (250 km/hr) and it is predicted that
the new potential wireless system will support 100 Mbps on mobility and 1
Gbps approximately on without mobility at lower cost. This potential new
wireless system could be developed by 2010. Its characteristics should be like
high degree of commonality of design worldwide to provide backward
compatibility, compatibility of services within IMT-Advanced and with the
fixed networks, high quality, and small terminal suitable for worldwide use,
worldwide roaming capability, capability to run high data rate multimedia
applications within a wide range of services and terminals.
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
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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
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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.
Currently marketed technologies such as LTE
(Long Term Evolution) and WiMAX have been around for a few years and are
being marketed as 4G whilst not meeting the requirements set by the ITU. It
was recently announced that these services could continue to be marketed as 4G
as they are precursors to the IMT-Advanced, 4G standard whilst also operating
on the same basis of technology; however, these should really be considered as
"Pre-4G" or "3.9G" as they technically do not offer the required data rates of
(stationary) 1Gbps.
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History of wireless communication (Fig.-1.1)
What is 4G?
4G takes on a number of equally true definitions, depending on who you are
talking to. In simplest terms, 4G is the next generation of wireless networks that
will replace 3G networks sometimes in future. In another context, 4G is simply
an initiative by academic R&D labs to move beyond the limitations and
problems of 3G which is having trouble getting deployed and meeting its
promised performance and throughout. In reality, as of first half of 2002, 4G is
a conceptual framework for or a discussion point to address future needs of a
universal high speed wireless network that will interface with wire line
backbone network seamlessly.
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
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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.
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 all-
encompassing 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 3 and4 demonstrate the key elements and the seamless
connectivity of the networks.
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Figures 2 and 3 demonstrate the key elements and the
seamless connectivity of the networks.
4G Mobile Communication Visions(fig.-1.2)
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Evolution of 4G Technology : In order to make smooth transition from 3G to 4G the mobile communication companies are promoting Super 3G/LTE. The companies are upgrading 3G Technology by initializing the introduction of High Speed Downlink Packet Access (HSDPA) service, which increases the downlink data rate of packet services, and by finalizing specifications for High Speed Uplink Packet Access (HSUPA), which enhances uplink speed. HSDPA and HSUPA cover area by 3-4 times relative to W-CDMA and by providing the high transmission rate with low cost per bit transmission. The main objective of the Super 3G is to construct simple, low cost system by removing the complexity from wireless network and mobile handsets. The 3G provides packet and voice services separately where as Super 3G is based on ALL-IP network covering both packet and voice services. As from diagram we can infer that by the 2010 we would be able to achieve the 1 Gbps in motion at low speed and 100 Mbps at high speed. On December 25, 2006, NTT DOCOMO became the first in the world to achieve a packet signal speed of 5 Gbps in an outdoor test in a low-speed environment (10 km/h). The test was undertaken to demonstrate the expected maximum transmission speed in an actual cell environment, taking into account interference from peripheral cells.
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TIMELINE OF THE EVALUATION OF 4G TECHNOLOGY(fig.-1.4)We are steadily approaching towards 4G wireless technologies by upgrading the current 3G technology by increasing the data rate speed and by reducing the cost of transmission which is the main objective of 4G wireless technology.
4G STANDARDS4G technology is meant to provide what is known as “ultra-broadband” access for mobile devices, and the International Telecommunications Union-Radio communications sector (ITU-R) created a set of standards that networks must meet in order to be considered 4G, known as the International Mobile Telecommunications Advanced (IMT-Advanced) specification.
First, 4G networks must be based on an all Internet protocol (IP) packet switching instead of circuit-switched technology, and use OFMDA multi-carrier transmission methods or other frequency-domain equalization (FDE) methods instead of current spread spectrum radio technology. In addition, peak data rates for 4G networks must be close to 100 megabit per second for a user on a highly mobile network and 1 gigabit per second for a user with local wireless access or a nomadic connection. True 4G must also be able to offer smooth handovers across differing networks without data loss and provide high quality of service for next-gen media. One of the most important aspects of 4G technology is the elimination of parallel circuit-switched and packet-switched network nodes using Internet Protocol version 6 (IPv6). The currently used standard, IPv4, has a finite limitation on the number of IP addresses that can be assigned to devices, meaning duplicate addresses must be created and reused using network address translation (NAT), a solution that only masks the problem instead of definitively solving it. IPv6 provides a much larger number of available addresses, and will be instrumental in providing a streamlined experience for users.
DEFINITION OF 4G TECHNOLOGY:
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4G mobile communications will have transmission rates up to 20 Mbps—higher
than of 3G. The technology is expected to be available by the year2010.
Presently, NTT Do Como and Hewlett-Packard are on their agenda to make it
available by the year 2006.4G is being developed with the following
objectives:1. Speeds up to 50 times higher than of 3G.However, the actual
available bandwidth of 4G is expected to be about 10 Mbps.2. Three-
dimensional virtual reality—imagine personal video avatars and realistic
holograms, and the ability to feel as if you are present at an event even if you
are not. People, places, and products will be able to interact as the cyber and
real world’s merge.3. Increased interaction between corroborating technologies;
the smart card in your phone will automatically pay for goods as you pass a
linked payment kiosk, or will tell your car to warm-up in the morning as your
phone has noted you leaving the house.Ericsson and the University of California
are jointly researching CDMA wireless access technology, advanced antenna
systems, next-generation mobile Internet, quality of service, power amplifier
technology, and wireless access net works. Other 4G applications include high-
performance streaming of multimedia content based on agent technology and
scalable media coding methods.
4G will solve problems like limited bandwidth in
3G when people are moving and uncertainty about the availability of bandwidth
for streaming to all users at all times. One of the key requirements is to realise a
wireless 4G IP-based access system. The ultimate objective is to create a
protocol suite and radio communication schemes to achieve broadband mobile
Communication in 4G wireless systems. Anew protocol suite for 4G wireless
systems
Supported by Department of Defense (DOD) contains:
1. Transport-layer protocols
2. Error-control protocols
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3. Medium-access protocol
4. Mobility management
5. Simulation test bed
6. Physical test bed
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
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Wireless System Evolution: Table 2.1. Short History of Mobile Telephone Technologies
Legend:
1xRTT = 2.5G CDMA data service up to 384 kbps AMPS = advanced mobile phone service CDMA = code division multiple access EDGE = enhanced data for global evolution FDMA = frequency division multiple access GPRS = general packet radio system GSM = global system for mobile
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NMT = Nordic mobile telephone PDC = personal digital cellular PSTN = pubic switched telephone network TACS = total access communications system TDMA = time division multiple access WCDMA = wideband CDMA
First generation: Almost all of the systems from this generation were analog systems where voice was considered to be the main traffic. These systems could often be listened to by third parties. Some of the standards are NMT, AMPS, Hicap, CDPD, Mobitex, DataTac, TACS and ETACS.
Second generation: All the standards belonging to this generation are commercial centric and they are digital in form. Around 60% of the current market is dominated by European standards. The second generation standards are GSM, iDEN, D-AMPS, IS-95, PDC, CSD, PHS, GPRS, HSCSD, and WiDEN.
Third generation: To meet the growing demands in network capacity, rates required for high speed data transfer and multimedia applications, 3G standards started evolving. The systems in this standard are essentially a linear enhancement of 2G systems. They are based on two parallel backbone infrastructures, one consisting of circuit switched nodes, and one ofpacket oriented nodes. The ITU defines a specific set of air interface technologies as third generation, as part of the IMT-2000 initiative. Currently, transition is happening from 2G to 3G systems. As a part of this transition, numerous technologies are being standardized.
Fourth generation: According to the 4G working groups, the infrastructure and the terminals of 4G will have almost all the standards from 2G to 4G implemented. Although legacy systems are in place to adopt existing users, the infrastructure for 4G will be only packet-based (all-IP). Some proposals suggest having an open platform where the new innovations and evolutions can fit. The technologies which are being considered as pre-4G are the following: WiMax, WiBro, iBurst, 3GPP Long Term Evolution and 3GPP2 Ultra Mobile Broadband.
KEY 4G TECHNOLOGIES:25
There are some key components for the successful deployment of the 4G wireless technology.
(A) OFDMA (Orthogonal Frequency Division Multiple Access)
Multipath phenomena in CDMA can tolerate long delay but it does not capture the entire energy, only fraction of the energy of the multipath signal because of limited no. of capability of taking the signal. In OFDM as from the below figure it can be understand the long guard band interval is long enough to absorb all inter-symbols-interference. 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 freedom. 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.
OFDMA PRINCIPLES (fig.-1.5)
In OFDM, a data stream is split into parallel lower data streams (a few kHz) that are modulated on separate subcarriers. The split the signal is called orthogonal subcarriers and these subcarriers are modulated by Inverse Discrete Fourier Transformation (IDFT) and hence it does not affect the signals on multipath effects. The long guard band is inserted between each OFDM symbol to absorb all inter signal symbols interference. This significantly improves the physical layer performance. The OFDM signal is also compatible with other enhancement technologies like smart antennas and MIMO.
Multiple access technology (Orthogonal Frequency Division Multiple Access; OFDMA) can also be used for modulation of OFDM. In this case, each OFDM signal symbol can transmit information to/from several users using a different set of subcarriers (subchannels). This not only
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provides additional flexibility for resource allocation (increasing the capacity), but also enables cross-layer optimization of radio link usage.
(B) Implementation of MIMO (multiple inputs, multiple outputs)
In order to improve the communication performance between sender and receiver, the multiple antennas are used at both transmitter and receiver end. MIMO multiplex the signals from the multiple transmitting antennas as it is suitable for OFDM because time symbols can be processed independently after OFDM waveform is correctly designed for the channel. This aspects of OFDM reduces the complexity while transmission and makes processing simple. The signal transmitted by m antennas and signal received by n antennas and the processing of the received signal may produce significant performance improvement such as range, quality of received signal and spectrum efficiency. Hence MIMO is more efficient when many multiple path signals are received. The gain in spectrum efficiency is directly related to the minimum number of antennas in the link. The MIMO enables significant increase in the data throughput and link range with additional bandwidth or transmit power. It achieves this by higher spectral efficiency more bits per second per hertz of bandwidth) and link reliability or diversity (reduced fading). Because of these properties MIMO has become current theme of wireless research.
(C) Smart antenna enhancements.
The main purpose of the radio communication depends on the advancements of the antennas which refer to smart or intelligent antennas. In early 90s, in order to meet growing data rate needs of the data communication, many transmission techniques were proposed such as spatial multiplexing which increases the bandwidth conservation and power efficiency. Spatial multiplexing provides the multiple deployment of antennas at the transmitting and receiving end and then independent streams of data can be transmitted as requested by the user can be transmitted simultaneously from the all transmitting antennas. Thus increasing the throughput into multiple folds with minimum number of the transmitting and receiving antennas.
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SMART ANTENNA PRINCIPLES (fig.-1.6)
There are two types of smart antennas which are switched beam smart antennas and adaptive array smart antennas. Switched beam systems have several available fixed beam patterns which help in making decisions as to which beam to access at any given point of time based on the requirements of the system. While adaptive arrays allow the antenna to steer the beam to any direction of interest while simultaneously nulling interfering signals. The reliability in transmitting high speed data in the fading channel can be improved by using more antennas at the transmitter or at the receiver. This is called transmit or receive diversity. Both transmit/receive diversity and transmit spatial multiplexing are categorized into the space-time coding techniques, which does not necessarily require the channel knowledge at the time of transmitting the signals. The other category is closed-loop multiple antenna technologies which use the channel knowledge at the transmitter.
(D) SDR (Software-Defined Radio) A basic SDR produces a radio that is capable of receiving and transmitting a different form of radio protocol (sometimes referred to as a waveform) as per the needs just by running different software. A SDR will allow to increase network capacity at specific time (e.g. during a sports event) and the operator can reconfigure its network by adding several modems at a given Base Transceiver Station (BTS). SDR will allow reconfigure network structure as per the needs. At the present SDR implementation is done by the infrastructure which develops multi-band, multi-standard base stations and terminals. SDR can be a powerful aid for manufacturer by providing multi-standard, multi-band equipment with reduced development effort and costs through simultaneous multi-channel processing. Software radios have significant utility for the military and cell phone services, both of which must serve a wide variety of
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changing radio protocols in real time. In the long term, software-defined radio is expected by its proponents to become the dominant technology in radio communications.
An Ideal Software Radio Receiver (fig.-1.7)
4G Technology Features :
(A)Incomparable Speed The majority of internet users choose a particular ISP over another because of the speed it offers. Even though I’ve used some slow and frustrating internet connections before I’ve also used a lot of super fast internet connections and I’m a great fan of the 3G technology. With all I’ve read so far the 4G mobile internet technology will be at least 10 times faster than the 3G mobile internet technology and that alone is enough speed than any individual will need.
(B) Advanced Security One thing about most forms of broadband internet technology despite their great speed is their security weakness. A lot of them have one or two features that make them highly vulnerable and even though the 4G internet technology is not perfect when it comes to security it has been designed in a way that makes it cover the weakness of other technologies. If you’re an internet user concerned a lot about security, with 4G, you really have no need to worry.
(C) Reliability and Effectiveness Irrespective of the Weather Condition The final thing I love the most about the 4G mobile internet technology is how reliable it is and also the fact that it isn’t affected by the weather. It can be really frustrating to be enjoying your broadband internet connection only to start experiencing problems due to harsh weather conditions. The 4G
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technology addresses all these and it won’t in any way be affected by the weather.
(D) Transfer Rate One of the things that changes from each generation of computers to the next is the speed at which they can transfer and process data. For instance, a third generation computer and computer network could transfer data up to 2 megabits per second. Fourth generation computers improved on that speed, with the ability to transfer data at up to 100 megabits per second. This higher bandwidth sets these two generations apart from previous ones, which could barely transfer data fast enough for streaming video.
(E) Wireless Technology3G and 4G computers and computer networks are some of the first to offer truly wireless capabilities. Wireless Internet works off of radio signals, the same kind used by cell phones. 3G computers have the ability to use and receive these wireless signals and thus you can make calls over a 3G computer or you can use wireless Internet. 4G computers and their networks take this further, adding power to the amount of data that can be transferred and the additional reception that 4G systems can provide.
4G MOBILE COMMUNICATIONSYSTEMSInternational Mobile Telecommunications’ - 2000(IMT-2000) and the Universal
Mobile Telecommunications System (UMTS) will be among the first 3G mobile
communication systems to offer wireless wideband multimedia services using
the Internet protocol. Two important technological changes will facilitate this
advancement. The first change is a shift from last-generation radio-access
technologies such as the global system for mobile (GSM) communication,
CDMA One (an IS-95 code division multiple access standard), and personal
digital cellular (PDC) toward more sophisticated systems with higher data-
transfer rates such as the enhanced data. fourth-generation mobile
communication systems will combine standardized streaming with arrange
unique services to provide high-quality content that meets the specific needs of
the rapidly growing mobile market. GSM environment (EDGE), wideband
CDMA (WCDMA), and cdma2000.As Figure 1 illustrates, the second important
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technology shift is from a vertically integrated to a horizontally layered service
environment. A horizontally layered4G service network seamlessly integrates
Internet protocol transport into a mobile service environment with a variety of
access networks, opening up many new opportunities for IP-based mobile
applications. For example, mobile terminals will be able to access existing
Internet content through protocols and markup languages such as WAP and
WML that are optimized for wireless application scenarios. 4Gmobile
communications will have transmission rates up to 20 Mbps_ higher than of 3G.
The technology is expected to be available by the year 2010. 4G is being
developed with the following objectives: 1. Speeds up to 50 times higher than of
3G. However, the actual available bandwidth of 4G is expected to be about 10
Mbps.2. Three-dimensional virtual reality_imagine personal video avatars and
realistic holograms, and the ability to feel as if you are present at an event even
if you are not. People, places, and products will be able to interact as the cyber
and real world’s merge.
APPLICATIONS OF 4G
The widespread implementation of mobile streaming services faces two major
challenges: access network and terminal heterogeneity, and content protection.
HeterogeneityIn the future, we will have access to a variety of mobile terminals with a wide
range of display sizes and capabilities. In addition, different radio-access
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networks will make multiple maximum-access link speeds available. Because of
the physical characteristics of cellular radio networks, the quality and, thus, the
data rate of an ongoing connection will also vary, contributing to the
heterogeneity problem. One way to address heterogeneity is to use appropriately
designed capability exchange mechanisms that enable the terminal and media
server to negotiate mobile terminal and mobile network capabilities and user
preferences. This approach lets the server send multimedia data adapted to the
user’s mobile terminal and the network. For example, a user accessing a specific
service via a WCDMA network could get the content delivered at a higher
bitrate than someone using a general packet radio service or GSM network.
Similarly, when a person using a mobile
Multimedia terminal with a built-in low quality speaker plugs in a high-fidelity
headphone; a dynamic capability exchange takes place, upgrading the
transmission to a high-quality audio stream for the remainder of the session. A
related problem is how to efficiently deliver streamed multimedia content over
various radio-access networks with different transmission conditions. This is
achievable
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The shift from a vertically integrated to a horizontally layered mobile service environment.
4Gnetwork seamlessly integrate Internet protocol transport with a variety of access networks
(fig.-1.8)
Virtual Presence: This means that the 4G provides user services at all times, even if the user is off-site.
Virtual navigation: 4G provides users with virtual navigation through which a user can access a database of a street, building, etc.
Tele-Medicine and Education: 4G will support remote health monitoring of patient. For people who are interested in lifelong education, 4G provides a good opportunity.
Other applications:
Voice, low-to-medium resolution images, moderate data rates. High quality audio, images with good quality on small screens (handset,
PDA, laptop PC). This can be achieved with WiMax, cable, satellite and DSL in supporting roles.
Wide coverage with HDTV quality images, hundreds of Mbps data rates. Broadcast HDTV, digital cable, satellite and next generations of WiMax/WiBro support this level of quality.
Local distribution of HDTV quality images, hundreds of Mbps data rates. UWB, 60 GHz systems, and other developing technologies can address this application area.
ADVANTAGES OF 4G:-1. Support for interactive multimedia services like teleconferencing and
wireless Internet.
2. Wider bandwidths and higher bitrates.
3. Global mobility and service portability.
4. Scalability of mobile network.
5. Entirely Packet-Switched networks.
6. Digital network elements.
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7. Higher band widths to provide multimedia services at lower cost (up to
100 Mbps).
8. Tight network security
LIMITATIONS:-1. Although the concept of 4G communications shows much promise,
there are still limitations that must be addressed. A major concern is
interoperability between the signaling techniques that are planned for
use in 4G (3XRTT and WCDMA).
2. Cost is another factor that could hamper the progress of 4G
technology. The equipment required to implement the next-generation
network are still very expensive.
3. A Key challenge facing deployment of 4G technologies is how to
make the network architectures compatible with each other. This was
one of the unmet goals of 3G.
4. AS regards the operating area, rural areas and many buildings in
metropolitan areas are not being served well by existing wireless
networks.
What is needed to Build 4G Networks of Future?
To achieve a 4G standard, a new approach is needed to avoid the divisiveness
we've seen in the 3G realm. One promising underlying technology to
accomplish this is multicarrier modulation (MCM), a derivative of frequency-
division multiplexing. Forms of multicarrier systems are currently used in
digital subscriber line (DSL) modems, and digital audio/video broadcast
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(DAB/DVB). MCM is a baseband process that uses parallel equal bandwidth
sub channels to transmit information. Normally implemented with Fast Fourier
transform (FFT) techniques, MCM's advantages include better performance in
the inter symbol interference (ISI) environment, and avoidance of single-
frequency interferers. However, MCM increases the peak-to-average ratio
(PAVR) of the signal, and to overcome ISI a cyclic extension or guard band
must be added to the data.
Cyclic extension works as follows: If N is the original length of a
block, and the channel's response is of length M, the cyclically extended symbol
has a new length of N + M - 1. The image presented by this sequence, to the
convolution with the channel, looks as if it was convolved with a periodic
sequence consisting of a repetition of the original block of N. Therefore, the
new symbol of length N + M - 1 sampling periods has no ISI. The cost is an
increase in energy and encoded bits added to the data. At the MCM receiver,
only N samples are processed, and M - 1 samples are discarded, resulting in a
loss in signal-to-noise ratio (SNR) as shown in Equation 1.
SNR loss=10 log ((N+M-1)/N) db-------- (1)
Two different types of MCM are likely candidates for 4G as listed in Table 1.
These include multicarrier code division multiple access (MC-CDMA) and
orthogonal frequency division multiplexing (OFDM) using time division
multiple access (TDMA). MC-CDMA is actually OFDM with a CDMA
overlay. Similar to single-carrier CDMA systems, the users are multiplexed
with orthogonal codes to distinguish users in MC-CDMA. However, in MC-
CDMA, each user can be allocated several codes, where the data is spread in
time or frequency. Either way, multiple users access the system simultaneously.
In OFDM with TDMA, the users are allocated time intervals to transmit and
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receive data. As with 3G systems, 4G systems have to deal with issues of
multiple access interference and timing.
CONCLUSION:System designers and services providers are looking forward to a true wireless
broadband cellular system, or 4G. To achieve the goals of 4G, technology will
need to improve significantly in order to handle the intensive algorithms in the
baseband processing and the wide bandwidth of a high PAVR signal. Novel
techniques will also have to be employed to help the system achieve the desired
capacity and throughput. High-performance signal processing will have to be
used for the antenna systems, power amplifier, and detection of the signal. A
number of spectrum allocation decisions, spectrum standardization decisions,
spectrum availability decisions, technology innovations, component
development, signal processing and switching enhancements and inter-vendor
cooperation have to take place before the vision of 4G will materialize. We
think that 3G experiences - good or bad, technological or business - will be
useful in guiding the industry in this effort. To sketch out a world where mobile
devices and services are ubiquitous and the promise of future fourth generation
(4G) mobile networks enables things only dreamed of, we believe that 4G will
probably become an IP-based network today.
The future may be bright, but it's in the hands of the customer, not the service provider and certainly not the network provider. 4G represents a significant evolution over the 3G standards, most notably in the removal of IP address limitations, increased data transfer rates and smooth handovers of clients over heterogeneous networks, but fully compliant technology is still in development and probably will be for some time. The advanced capabilities of LTE networks are quickly utilizing the speeds promised by 4G. Just in time for the development of 5G.
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GLOBAL MARKET OF 4G (fig.-1.9)
Reference1. http://www.seminarprojects.com/Thread-4g-mobile-communication-system-a-
seminar-report#ixzz1ZzgENyWK
2. www.flarion.com
3. http://www.net work magazine.com4.www.ist-wsi.org
4. www.nttdocomo.com
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