4G

4G

Overview
In telecommunication
Telecommunication
Telecommunication is the transmission of information over significant distances to communicate. In earlier times, telecommunications involved the use of visual signals, such as beacons, smoke signals, semaphore telegraphs, signal flags, and optical heliographs, or audio messages via coded...

s, 4G is the fourth generation of cellular
Cellular
Cellular may refer to:*Cellular automaton, a model in discrete mathematics*Cellular , a 2004 movie*Cellular frequencies, assigned to networks operating in cellular RF bands*Cellular manufacturing...

 wireless
Wireless
Wireless telecommunications is the transfer of information between two or more points that are not physically connected. Distances can be short, such as a few meters for television remote control, or as far as thousands or even millions of kilometers for deep-space radio communications...

 standards. It is a successor to the 3G
3G
3G or 3rd generation mobile telecommunications is a generation of standards for mobile phones and mobile telecommunication services fulfilling the International Mobile Telecommunications-2000 specifications by the International Telecommunication Union...

 and 2G
2G
2G is short for second-generation wireless telephone technology. Second generation 2G cellular telecom networks were commercially launched on the GSM standard in Finland by Radiolinja in 1991...

 families of standards. In 2009, the ITU-R
ITU-R
The ITU Radiocommunication Sector is one of the three sectors of the International Telecommunication Union and is responsible for radio communication....

 organization specified the IMT-Advanced (International Mobile Telecommunications Advanced) requirements for 4G standards, setting peak speed requirements for 4G service 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
Internet Protocol
The Internet Protocol is the principal communications protocol used for relaying datagrams across an internetwork using the Internet Protocol Suite...

 based mobile broadband
Mobile Broadband
Mobile broadband is the marketing term for wireless Internet access through a portable modem, mobile phone or other mobile device.-Description:...

 solution to laptop computer wireless modem
Wireless modem
A wireless modem is a type of modulator-demodulator which connects to a wireless network instead of using telephone or cable television lines...

s, smartphones, and other mobile devices.
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In telecommunication
Telecommunication
Telecommunication is the transmission of information over significant distances to communicate. In earlier times, telecommunications involved the use of visual signals, such as beacons, smoke signals, semaphore telegraphs, signal flags, and optical heliographs, or audio messages via coded...

s, 4G is the fourth generation of cellular
Cellular
Cellular may refer to:*Cellular automaton, a model in discrete mathematics*Cellular , a 2004 movie*Cellular frequencies, assigned to networks operating in cellular RF bands*Cellular manufacturing...

 wireless
Wireless
Wireless telecommunications is the transfer of information between two or more points that are not physically connected. Distances can be short, such as a few meters for television remote control, or as far as thousands or even millions of kilometers for deep-space radio communications...

 standards. It is a successor to the 3G
3G
3G or 3rd generation mobile telecommunications is a generation of standards for mobile phones and mobile telecommunication services fulfilling the International Mobile Telecommunications-2000 specifications by the International Telecommunication Union...

 and 2G
2G
2G is short for second-generation wireless telephone technology. Second generation 2G cellular telecom networks were commercially launched on the GSM standard in Finland by Radiolinja in 1991...

 families of standards. In 2009, the ITU-R
ITU-R
The ITU Radiocommunication Sector is one of the three sectors of the International Telecommunication Union and is responsible for radio communication....

 organization specified the IMT-Advanced (International Mobile Telecommunications Advanced) requirements for 4G standards, setting peak speed requirements for 4G service 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
Internet Protocol
The Internet Protocol is the principal communications protocol used for relaying datagrams across an internetwork using the Internet Protocol Suite...

 based mobile broadband
Mobile Broadband
Mobile broadband is the marketing term for wireless Internet access through a portable modem, mobile phone or other mobile device.-Description:...

 solution to laptop computer wireless modem
Wireless modem
A wireless modem is a type of modulator-demodulator which connects to a wireless network instead of using telephone or cable television lines...

s, smartphones, and other mobile devices. Facilities such as ultra-broadband
Ultra Mobile Broadband
UMB was the brand name for a project within 3GPP2 to improve the CDMA2000 mobile phone standard for next generation applications and requirements...

 Internet access, IP telephony, gaming services, and streamed multimedia may be provided to users.

IMT-Advanced compliant versions of LTE and WiMAX are under development and called "LTE Advanced
LTE Advanced
LTE Advanced is a preliminary mobile communication standard, formally submitted as a candidate 4G system to ITU-T in late 2009, was approved into ITU, International Telecommunications Union, IMT-Advanced and expected to be finalized by 3GPP in early 2011...

" and "WirelessMAN-Advanced" respectively. ITU has decided that LTE Advanced and WirelessMAN-Advanced should be accorded the official designation of IMT-Advanced. On December 6, 2010, ITU recognized that current versions of LTE, WiMax and other evolved 3G technologies that do not fulfill "IMT-Advanced" requirements could nevertheless be considered "4G", provided they represent forerunners to IMT-Advanced and "a substantial level of improvement in performance and capabilities with respect to the initial third generation systems now deployed."

As seen below, in all suggestions for 4G, the CDMA spread spectrum
Spread spectrum
Spread-spectrum techniques are methods by which a signal generated in a particular bandwidth is deliberately spread in the frequency domain, resulting in a signal with a wider bandwidth...

 radio technology used in 3G systems and IS-95
IS-95
Interim Standard 95 is the first CDMA-based digital cellular standard by Qualcomm. The brand name for IS-95 is cdmaOne. IS-95 is also known as TIA-EIA-95....

 is abandoned and replaced by OFDMA
OFDMA
Orthogonal Frequency-Division Multiple Access is a multi-user version of the popular Orthogonal frequency-division multiplexing digital modulation scheme. Multiple access is achieved in OFDMA by assigning subsets of subcarriers to individual users as shown in the illustration below...

 and other frequency-domain equalization
Single-carrier FDMA
Single-carrier FDMA is a frequency-division multiple access scheme. Like other multiple access schemes , it deals with the assignment of multiple users to a shared communication resource...

 schemes. This is combined with MIMO
MIMO
In radio, multiple-input and multiple-output, or MIMO , is the use of multiple antennas at both the transmitter and receiver to improve communication performance. It is one of several forms of smart antenna technology...

 (Multiple In Multiple Out), e.g., multiple antennas, dynamic channel allocation and channel-dependent scheduling.

Background


The nomenclature of the generations generally refers to a change in the fundamental nature of the service, non-backwards compatible transmission technology, higher spectral bandwidth and new frequency bands. New generations have appeared about every ten years since the first move from 1981 analog (1G) to digital (2G) transmission in 1992. This was followed, in 2001, by 3G multi-media support, spread spectrum
Spread spectrum
Spread-spectrum techniques are methods by which a signal generated in a particular bandwidth is deliberately spread in the frequency domain, resulting in a signal with a wider bandwidth...

 transmission and at least 200 kbit/s, in 2011 expected to be followed by 4G, which refers to all-IP
Internet Protocol
The Internet Protocol is the principal communications protocol used for relaying datagrams across an internetwork using the Internet Protocol Suite...

 packet-switched
Packet switching
Packet switching is a digital networking communications method that groups all transmitted data – regardless of content, type, or structure – into suitably sized blocks, called packets. Packet switching features delivery of variable-bit-rate data streams over a shared network...

 networks, mobile ultra-broadband (gigabit speed) access and multi-carrier transmission.

The fastest 3G based standard in the WCDMA family is the HSPA+ standard, which was commercially available in 2009 and offers 28 Mbit/s downstreams without MIMO
MIMO
In radio, multiple-input and multiple-output, or MIMO , is the use of multiple antennas at both the transmitter and receiver to improve communication performance. It is one of several forms of smart antenna technology...

, i.e. only with one antenna (it would offer 56 Mbit/s with 2x2 MIMO), and 22 Mbit/s upstreams. The fastest 3G based standard in the CDMA2000
CDMA2000
CDMA2000 is a family of 3G mobile technology standards, which use CDMA channel access, to send voice, data, and signaling data between mobile phones and cell sites. The set of standards includes: CDMA2000 1X, CDMA2000 EV-DO Rev. 0, CDMA2000 EV-DO Rev. A, and CDMA2000 EV-DO Rev. B...

 family is the EV-DO Rev. B, which was available in 2010 and offers 15.67 Mbit/s downstreams.

Requirements


In mid 1990s, the ITU-R
ITU-R
The ITU Radiocommunication Sector is one of the three sectors of the International Telecommunication Union and is responsible for radio communication....

 organization specified the IMT-2000 specifications for what standards that should be considered 3G
3G
3G or 3rd generation mobile telecommunications is a generation of standards for mobile phones and mobile telecommunication services fulfilling the International Mobile Telecommunications-2000 specifications by the International Telecommunication Union...

 systems. However, the cell phone market brands only some of the IMT-2000 standards as 3G (e.g. WCDMA and CDMA2000), not all (3GPP EDGE, DECT and mobile-WiMAX
WiMAX
WiMAX is a communication technology for wirelessly delivering high-speed Internet service to large geographical areas. The 2005 WiMAX revision provided bit rates up to 40 Mbit/s with the 2011 update up to 1 Gbit/s for fixed stations...

 all fulfil the IMT-2000 requirements and are formally accepted as 3G standards, but are typically not branded as 3G). In 2008, ITU-R specified the IMT-Advanced (International Mobile Telecommunications Advanced) requirements for 4G systems.

This article uses 4G to refer to IMT-Advanced (International Mobile Telecommunications Advanced), as defined by ITU-R
ITU-R
The ITU Radiocommunication Sector is one of the three sectors of the International Telecommunication Union and is responsible for radio communication....

. An IMT-Advanced cellular system
Mobile phone
A mobile phone is a device which can make and receive telephone calls over a radio link whilst moving around a wide geographic area. It does so by connecting to a cellular network provided by a mobile network operator...

 must fulfill the following requirements:
  • Based on an all-IP packet switched network.
  • 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.
  • Dynamically share and use the network resources to support more simultaneous users per cell.
  • Scalable channel bandwidth 5–20 MHz, optionally up to 40 MHz.
  • Peak link spectral efficiency of 15 bit/s/Hz in the downlink, and 6.75 bit/s/Hz in the uplink (meaning that 1 Gbit/s in the downlink should be possible over less than 67 MHz bandwidth).
  • System spectral efficiency of up to 3 bit/s/Hz/cell in the downlink and 2.25 bit/s/Hz/cell for indoor usage.
  • Smooth handovers across heterogeneous networks.
  • Ability to offer high quality of service for next generation multimedia support.


In September 2009, the technology proposals were submitted to the International Telecommunication Union (ITU) as 4G candidates. Basically all proposals are based on two technologies:
  • LTE Advanced
    LTE Advanced
    LTE Advanced is a preliminary mobile communication standard, formally submitted as a candidate 4G system to ITU-T in late 2009, was approved into ITU, International Telecommunications Union, IMT-Advanced and expected to be finalized by 3GPP in early 2011...

     standardized by the 3GPP
    3GPP
    The 3rd Generation Partnership Project is a collaboration between groups of telecommunications associations, known as the Organizational Partners...

  • 802.16m standardized by the IEEE (i.e. WiMAX)


Present implementations of WiMAX and LTE are largely considered a stopgap solution that will offer a considerable boost while WiMAX 2 (based on the 802.16m spec) and LTE Advanced are finalized. Both technologies aim to reach the objectives traced by the ITU, but are still far from being implemented.

The first set of 3GPP requirements on LTE Advanced was approved in June 2008. LTE Advanced will be standardized in 2010 as part of the Release 10 of the 3GPP specification. LTE Advanced will be fully built on the existing LTE specification Release 10 and not be defined as a new specification series. A summary of the technologies that have been studied as the basis for LTE Advanced is included in a technical report.

Current LTE and WiMAX implementations are considered pre-4G, as they do not fully comply with the planned requirements of 1 Gbit/s for stationary reception and 100 Mbit/s for mobile.

Confusion has been caused by some mobile carriers who have launched products advertised as 4G but which are actually current technologies, commonly referred to as '3.9G', which do not follow the ITU-R defined principles for 4G standards. A common argument for branding 3.9G systems as new-generation is that they use different frequency bands to 3G technologies; that they are based on a new radio-interface paradigm; and that the standards are not backwards compatible with 3G, whilst some of the standards are expected to be forwards compatible with "real" 4G technologies.

While the ITU has adopted recommendations for technologies that would be used for future global communications, they do not actually perform the standardization or development work themselves, instead relying on the work of other standards bodies such as IEEE, The WiMAX Forum and 3GPP. Recently, ITU-R Working Party 5D approved two industry-developed technologies (LTE Advanced and WirelessMAN-Advanced) for inclusion in the ITU’s International Mobile Telecommunications Advanced (IMT-Advanced program), which is focused on global communication systems that would be available several years from now.

4G and near-4G systems


The wireless telecommunications industry as a whole has early assumed the term 4G as a shorthand way to describe those advanced cellular technologies that, among other things, are based on or employ wide channel OFDMA and SC-FDE technologies, MIMO
MIMO
In radio, multiple-input and multiple-output, or MIMO , is the use of multiple antennas at both the transmitter and receiver to improve communication performance. It is one of several forms of smart antenna technology...

 transmission and an all-IP based architecture. Mobile-WiMAX, first release LTE, IEEE 802.20 as well as Flash-OFDM meets these early assumptions, and have been considered as 4G candidate systems, but do not yet meet the more recent ITU-R IMT-Advanced requirements.

LTE Advanced

See also: 3GPP Long Term Evolution (LTE) below


LTE Advanced
LTE Advanced
LTE Advanced is a preliminary mobile communication standard, formally submitted as a candidate 4G system to ITU-T in late 2009, was approved into ITU, International Telecommunications Union, IMT-Advanced and expected to be finalized by 3GPP in early 2011...

 (Long-term-evolution Advanced) is a candidate for IMT-Advanced standard, formally submitted by the 3GPP
3GPP
The 3rd Generation Partnership Project is a collaboration between groups of telecommunications associations, known as the Organizational Partners...

 organization to ITU-T in the fall 2009, and expected to be released in 2012. The target of 3GPP LTE Advanced is to reach and surpass the ITU requirements. LTE Advanced is essentially an enhancement to LTE. It is not a new technology but rather an improvement on the existing LTE network. This upgrade path makes it more cost effective for vendors to offer LTE and then upgrade to LTE Advanced which is similar to the upgrade from WCDMA to HSPA. LTE and LTE Advanced will also make use of additional spectrum and multiplexing to allow it to achieve higher data speeds. Coordinated Multi-point Transmission will also allow more system capacity to help handle the enhanced data speeds. Release 10 of LTE is expected to achieve the LTE Advanced speeds. Release 8 currently supports up to 300 Mbit/s download speeds which is still short of the IMT-Advanced standards.
Data speeds of LTE Advanced
LTE Advanced
Peak Download 1 Gbit/s
Peak Upload 500 Mbit/s

IEEE 802.16m or WirelessMAN-Advanced


The IEEE 802.16m or WirelessMAN-Advanced evolution of 802.16e is under development, with the objective to fulfill the IMT-Advanced criteria of 1 Gbit/s for stationary reception and 100 Mbit/s for mobile reception.

3GPP Long Term Evolution (LTE)

See also: LTE Advanced above

The pre-4G technology 3GPP Long Term Evolution
3GPP Long Term Evolution
3GPP Long Term Evolution, usually referred to as LTE, is a standard for wireless communication of high-speed data for mobile phones and data terminals. It is based on the GSM/EDGE and UMTS/HSPA network technologies, increasing the capacity and speed using new modulation techniques...

 (LTE) is often branded "4G", but the first LTE release does not fully comply with the IMT-Advanced requirements. LTE has a theoretical net bit rate capacity of up to 100 Mbit/s in the downlink and 50 Mbit/s in the uplink if a 20 MHz channel is used — and more if multiple-input multiple-output (MIMO), i.e. antenna arrays, are used.

The physical radio interface was at an early stage named High Speed OFDM Packet Access (HSOPA), now named Evolved UMTS Terrestrial Radio Access (E-UTRA).
The first LTE
3GPP Long Term Evolution
3GPP Long Term Evolution, usually referred to as LTE, is a standard for wireless communication of high-speed data for mobile phones and data terminals. It is based on the GSM/EDGE and UMTS/HSPA network technologies, increasing the capacity and speed using new modulation techniques...

 USB dongles do not support any other radio interface.

The world's first publicly available LTE service was opened in the two Scandinavian capitals Stockholm
Stockholm
Stockholm is the capital and the largest city of Sweden and constitutes the most populated urban area in Scandinavia. Stockholm is the most populous city in Sweden, with a population of 851,155 in the municipality , 1.37 million in the urban area , and around 2.1 million in the metropolitan area...

 (Ericsson
Ericsson
Ericsson , one of Sweden's largest companies, is a provider of telecommunication and data communication systems, and related services, covering a range of technologies, including especially mobile networks...

 and Nokia Siemens Networks
Nokia Siemens Networks
Nokia Siemens Networks is a global data networking and telecommunications equipment company headquartered in Espoo, Finland. It is a joint venture between Nokia of Finland and Siemens of Germany...

 systems) and Oslo
Oslo
Oslo is a municipality, as well as the capital and most populous city in Norway. As a municipality , it was established on 1 January 1838. Founded around 1048 by King Harald III of Norway, the city was largely destroyed by fire in 1624. The city was moved under the reign of Denmark–Norway's King...

 (a Huawei
Huawei
Huawei is a Chinese multinational networking and telecommunications equipment and services company headquartered in Shenzhen, Guangdong, China...

 system) on 14 December 2009, and branded 4G. The user terminals were manufactured by Samsung. Currently, the two publicly available LTE services in the United States are provided by MetroPCS
MetroPCS
MetroPCS Communications, Inc. , formerly known as General Wireless, Inc., is an American mobile phone service provider. It operates the fifth largest mobile telecommunications network in the US, with 8.9 million subscribers as of May 2011...

, and Verizon Wireless
Verizon Wireless
Cellco Partnership, doing business as Verizon Wireless, is one of the largest mobile network operators in the United States. The network has 107.7 million subscribers as of 2011, making it the largest wireless service provider in America....

. AT&T
AT&T
AT&T Inc. is an American multinational telecommunications corporation headquartered in Whitacre Tower, Dallas, Texas, United States. It is the largest provider of mobile telephony and fixed telephony in the United States, and is also a provider of broadband and subscription television services...

 also has an LTE service in planned for deployment between mid-2011 and end of 2013, Sprint Nextel
Sprint Nextel
Sprint Nextel Corporation is an American telecommunications company based in Overland Park, Kansas. The company owns and operates Sprint, the third largest wireless telecommunications network in the United States, with 53.4 million customers, behind Verizon Wireless and AT&T Mobility...

 has stated it's considering switching from WiMax
WiMAX
WiMAX is a communication technology for wirelessly delivering high-speed Internet service to large geographical areas. The 2005 WiMAX revision provided bit rates up to 40 Mbit/s with the 2011 update up to 1 Gbit/s for fixed stations...

 to LTE in the near future.

In South Korea, SK Telecom and LG U+ have enabled access to LTE service since 1 July 2011 for data devices, slated to go nationwide by 2012.
Data speeds of LTE
LTE
Peak Download 100 Mbit/s
Peak Upload 50 Mbit/s

Mobile WiMAX (IEEE 802.16e)


The Mobile WiMAX (IEEE 802.16e-2005) mobile wireless broadband access (MWBA) standard (also known as WiBro
WiBro
WiBro is a wireless broadband Internet technology developed by the South Korean telecoms industry. WiBro is the South Korean service name for IEEE 802.16e international standard...

 in South Korea) is sometimes branded 4G, and offers peak data rates of 128 Mbit/s downlink and 56 Mbit/s uplink over 20 MHz wide channels .

In June 2006, the world's first commercial mobile WiMAX service was opened by KT in Seoul
Seoul
Seoul , officially the Seoul Special City, is the capital and largest metropolis of South Korea. A megacity with a population of over 10 million, it is the largest city proper in the OECD developed world...

, South Korea
South Korea
The Republic of Korea , , is a sovereign state in East Asia, located on the southern portion of the Korean Peninsula. It is neighbored by the People's Republic of China to the west, Japan to the east, North Korea to the north, and the East China Sea and Republic of China to the south...

.

Sprint Nextel
Sprint Nextel
Sprint Nextel Corporation is an American telecommunications company based in Overland Park, Kansas. The company owns and operates Sprint, the third largest wireless telecommunications network in the United States, with 53.4 million customers, behind Verizon Wireless and AT&T Mobility...

 has begun using Mobile WiMAX, as of September 29, 2008 branded as a "4G" network even though the current version does not fulfil the IMT Advanced requirements on 4G systems.

In Russia, Belarus and Nicaragua WiMax broadband internet access is offered by a Russian company Scartel, and is also branded 4G, Yota
Yota
Yota is the trademark of a Russian multinational telecommunications services provider . Yota currently operates in Russia, Belarus and Nicaragua and will launch in Peru very soon...

.
Data speeds of WiMAX
WiMAX
Peak Download 128 Mbit/s
Peak Upload 64 Mbit/s

UMB (formerly EV-DO Rev. C)


UMB (Ultra Mobile Broadband
Ultra Mobile Broadband
UMB was the brand name for a project within 3GPP2 to improve the CDMA2000 mobile phone standard for next generation applications and requirements...

) was the brand name for a discontinued 4G project within the 3GPP2 standardization group to improve the CDMA2000
CDMA2000
CDMA2000 is a family of 3G mobile technology standards, which use CDMA channel access, to send voice, data, and signaling data between mobile phones and cell sites. The set of standards includes: CDMA2000 1X, CDMA2000 EV-DO Rev. 0, CDMA2000 EV-DO Rev. A, and CDMA2000 EV-DO Rev. B...

 mobile phone standard for next generation applications and requirements. In November 2008, Qualcomm
Qualcomm
Qualcomm is an American global telecommunication corporation that designs, manufactures and markets digital wireless telecommunications products and services based on its code division multiple access technology and other technologies. Headquartered in San Diego, CA, USA...

, UMB's lead sponsor, announced it was ending development of the technology, favouring LTE instead. The objective was to achieve data speeds over 275 Mbit/s downstream and over 75 Mbit/s upstream.

Flash-OFDM


At an early stage the Flash-OFDM system was expected to be further developed into a 4G standard.

iBurst and MBWA (IEEE 802.20) systems


The iBurst
IBurst
iBurst is a wireless broadband technology originally developed by ArrayComm. It optimizes the use of its bandwidth with the help of smart antennas...

 system ( or HC-SDMA, High Capacity Spatial Division Multiple Access) was at an early stage considered as a 4G predecessor. It was later further developed into the Mobile Broadband Wireless Access (MBWA) system, also known as IEEE 802.20.

Data rate comparison


The following table shows a comparison of 4G candidate systems as well as other competing technologies.

Objectives assumed in the literature


4G is being developed to accommodate the quality of service
Quality of service
The quality of service refers to several related aspects of telephony and computer networks that allow the transport of traffic with special requirements...

 (QoS) and rate requirements set by further development of existing 3G applications like mobile broadband
Mobile Broadband
Mobile broadband is the marketing term for wireless Internet access through a portable modem, mobile phone or other mobile device.-Description:...

 access, Multimedia Messaging Service
Multimedia Messaging Service
Multimedia Messaging Service, or MMS, is a standard way to send messages that include multimedia content to and from mobile phones. It extends the core SMS capability that allowed exchange of text messages only up to 160 characters in length.The most popular use is to send photographs from...

 (MMS), video chat
Videoconferencing
Videoconferencing is the conduct of a videoconference by a set of telecommunication technologies which allow two or more locations to interact via two-way video and audio transmissions simultaneously...

, mobile TV
Mobile TV
Mobile television usually means television watched on a small handheld device. It may be a pay TV service broadcast on mobile phone networks or received free-to-air via terrestrial television stations from either regular broadcast or a special mobile TV transmission format...

, but also new services like HDTV
High-definition television
High-definition television is video that has resolution substantially higher than that of traditional television systems . HDTV has one or two million pixels per frame, roughly five times that of SD...

. 4G may allow roaming with wireless local area networks, and may interact with digital video broadcasting systems.

In the literature, the assumed or expected 4G requirements have changed during the years before IMT-Advanced was specified by the ITU-R. These are examples of objectives stated in various sources:
  • A nominal data rate of 100 Mbit/s while the client physically moves at high speeds relative to the station, and 1 Gbit/s while client and station are in relatively fixed positions as defined by the ITU-R
    ITU-R
    The ITU Radiocommunication Sector is one of the three sectors of the International Telecommunication Union and is responsible for radio communication....

  • A data rate of at least 100 Mbit/s between any two points in the world
  • Smooth handoff across heterogeneous networks
  • Seamless connectivity and global roaming
    Roaming
    In wireless telecommunications, roaming is a general term referring to the extension of connectivity service in a location that is different from the home location where the service was registered. Roaming ensures that the wireless device is kept connected to the network, without losing the...

     across multiple networks
  • High quality of service for next generation multimedia support (real time audio, high speed data, HDTV video content, mobile TV, etc.)
  • Interoperability with existing wireless standards
  • An all IP, packet switched network
  • IP-based femtocell
    Femtocell
    In telecommunications, a femtocell is a small cellular base station, typically designed for use in a home or small business. It connects to the service provider’s network via broadband ; current designs typically support 2 to 4 active mobile phones in a residential setting, and 8 to 16 active...

    s (home nodes connected to fixed Internet broadband infrastructure)

Principal technologies

  • Physical layer transmission techniques are as follows:
    • MIMO
      MIMO
      In radio, multiple-input and multiple-output, or MIMO , is the use of multiple antennas at both the transmitter and receiver to improve communication performance. It is one of several forms of smart antenna technology...

      : To attain ultra high spectral efficiency by means of spatial processing including multi-antenna and multi-user MIMO
    • Frequency-domain-equalization, for example multi-carrier modulation (OFDM) in the downlink or single-carrier frequency-domain-equalization (SC-FDE) in the uplink: To exploit the frequency selective channel property without complex equalization
    • Frequency-domain statistical multiplexing, for example (OFDMA
      OFDMA
      Orthogonal Frequency-Division Multiple Access is a multi-user version of the popular Orthogonal frequency-division multiplexing digital modulation scheme. Multiple access is achieved in OFDMA by assigning subsets of subcarriers to individual users as shown in the illustration below...

      ) or (single-carrier FDMA) (SC-FDMA, a.k.a. linearly precoded OFDMA, LP-OFDMA) in the uplink: Variable bit rate by assigning different sub-channels to different users based on the channel conditions
    • Turbo principle
      Turbo code
      In information theory, turbo codes are a class of high-performance forward error correction codes developed in 1993, which were the first practical codes to closely approach the channel capacity, a theoretical maximum for the code rate at which reliable communication is still possible given a...

       error-correcting codes: To minimize the required SNR
      Signal-to-noise ratio
      Signal-to-noise ratio is a measure used in science and engineering that compares the level of a desired signal to the level of background noise. It is defined as the ratio of signal power to the noise power. A ratio higher than 1:1 indicates more signal than noise...

       at the reception side
  • Channel-dependent scheduling: To utilize the time-varying channel
  • Link adaptation
    Link adaptation
    Link adaptation, or adaptive coding and modulation , is a term used in wireless communications to denote the matching of the modulation, coding and other signal and protocol parameters to the conditions on the radio link Link adaptation, or adaptive coding and modulation (ACM), is a term used in...

    : Adaptive modulation and error-correcting codes
  • Relaying, including fixed relay networks (FRNs), and the cooperative relaying concept, known as multi-mode protocol

4G features assumed in early literature


The 4G system was originally envisioned by the Defense Advanced Research Projects Agency (DARPA). The DARPA selected the distributed architecture and end-to-end Internet protocol (IP), and believed at an early stage in peer-to-peer networking in which every mobile device would be both a transceiver and a router for other devices in the network, eliminating the spoke-and-hub weakness of 2G and 3G cellular systems. Since the 2.5G GPRS system, cellular systems have provided dual infrastructures: packet switched nodes for data services, and circuit switched nodes for voice calls. In 4G systems, the circuit-switched infrastructure is abandoned and only a packet-switched network is provided, while 2.5G and 3G systems require both packet-switched and circuit-switched network nodes, i.e. two infrastructures in parallel. This means that in 4G, traditional voice calls are replaced by IP telephony.

Cellular systems such as 4G allow seamless mobility; thus a file transfer is not interrupted in case a terminal moves from one cell (one base station coverage area) to another, but handover
Handover
In cellular telecommunications, the term handover or handoff refers to the process of transferring an ongoing call or data session from one channel connected to the core network to another...

 is carried out. The terminal also keeps the same IP address while moving, meaning that a mobile server is reachable as long as it is within the coverage area of any server. In 4G systems this mobility is provided by the mobile IP
Mobile IP
Mobile IP is an Internet Engineering Task Force standard communications protocol that is designed to allow mobile device users to move from one network to another while maintaining a permanent IP address. Mobile IP for IPv4 is described in IETF RFC 5944, and extensions are defined in IETF RFC 4721...

 protocol, part of IP version 6, while in earlier cellular generations it was provided only by physical-layer and datalink-layer protocols. In addition to seamless mobility, 4G provides flexible interoperability of the various kinds of existing wireless networks, such as satellite, cellular wireless, WLAN, PAN and systems for accessing fixed wireless networks.

While maintaining seamless mobility, 4G will offer very high data rates with expectations of 100 Mbit/s wireless service. The increased bandwidth and higher data transmission rates will allow 4G users the ability to utilize high-definition video and the videoconferencing features of mobile devices attached to a 4G network. The 4G wireless system is expected to provide a comprehensive IP solution where multimedia applications and services can be delivered to the user on an 'anytime, anywhere' basis with a satisfactory high data rate, premium quality and high security.

4G is described as MAGIC: mobile multimedia, anytime anywhere, global mobility support, integrated wireless solution, and customized personal service.
Some key features (primarily from users' points of view) of 4G mobile networks are:
  • High usability: anytime, anywhere, and with any technology
  • Support for multimedia services at low transmission cost
  • Personalization
  • Integrated services

Multiplexing and Access schemes



As the wireless standards evolved, the access techniques used also exhibited increase in efficiency, capacity and scalability. The first generation wireless standards used plain TDMA
Time division multiple access
Time division multiple access is a channel access method for shared medium networks. It allows several users to share the same frequency channel by dividing the signal into different time slots. The users transmit in rapid succession, one after the other, each using its own time slot. This...

 and FDMA. In the wireless channels, TDMA proved to be less efficient in handling the high data rate channels as it requires large guard periods to alleviate the multipath impact. Similarly, FDMA consumed more bandwidth for guard to avoid inter carrier interference. So in second generation systems, one set of standard used the combination of FDMA and TDMA and the other set introduced an access scheme called CDMA. Usage of CDMA increased the system capacity, but as a theoretical drawback placed a soft limit on it rather than the hard limit (i.e. a CDMA network setup does not inherently reject new clients when it approaches its limits, resulting in a denial of service to all clients when the network overloads; though this outcome is avoided in practical implementations by admission control of circuit switched or fixed bitrate communication services). Data rate is also increased as this access scheme (providing the network is not reaching its capacity) is efficient enough to handle the multipath channel. This enabled the third generation systems, such as IS-2000, UMTS, HSXPA
High Speed Packet Access
High Speed Packet Access is an amalgamation of two mobile telephony protocols, High Speed Downlink Packet Access and High Speed Uplink Packet Access , that extends and improves the performance of existing WCDMA protocols...

, 1xEV-DO, TD-CDMA
TD-CDMA
TD-CDMA, an acronym for Time-division - CDMA, is a channel access method based on using spread spectrum across multiple time slots. It is shown that a mixture of TDMA and CDMA provides better quality of service for multimedia communications in terms of data throughput and voice/video...

 and TD-SCDMA
TD-SCDMA
Time Division Synchronous Code Division Multiple Access or UTRA/UMTS-TDD 1.28 Mcps Low Chip Rate , is an air interface found in UMTS mobile telecommunications networks in China as an alternative to W-CDMA. Together with TD-CDMA, it is also known as UMTS-TDD or IMT 2000 Time-Division .The term...

, to use CDMA as the access scheme. However, the issue with CDMA is that it suffers from poor spectral flexibility and computationally intensive time-domain equalization (high number of multiplications per second) for wideband channels.

Recently, new access schemes like Orthogonal FDMA
OFDMA
Orthogonal Frequency-Division Multiple Access is a multi-user version of the popular Orthogonal frequency-division multiplexing digital modulation scheme. Multiple access is achieved in OFDMA by assigning subsets of subcarriers to individual users as shown in the illustration below...

 (OFDMA), Single Carrier FDMA (SC-FDMA), Interleaved FDMA and Multi-carrier CDMA
Multi-carrier code division multiple access
Multi-Carrier Code Division Multiple Access is a multiple access scheme used in OFDM-based telecommunication systems, allowing the system to support multiple users at the same time.MC-CDMA spreads each user symbol in the frequency domain...

 (MC-CDMA) are gaining more importance for the next generation systems. These are based on efficient FFT algorithms and frequency domain equalization, resulting in a lower number of multiplications per second. They also make it possible to control the bandwidth and form the spectrum in a flexible way. However, they require advanced dynamic channel allocation and traffic adaptive scheduling.

WiMax
WiMAX
WiMAX is a communication technology for wirelessly delivering high-speed Internet service to large geographical areas. The 2005 WiMAX revision provided bit rates up to 40 Mbit/s with the 2011 update up to 1 Gbit/s for fixed stations...

 is using OFDMA in the downlink and in the uplink. For the next generation UMTS
3GPP Long Term Evolution
3GPP Long Term Evolution, usually referred to as LTE, is a standard for wireless communication of high-speed data for mobile phones and data terminals. It is based on the GSM/EDGE and UMTS/HSPA network technologies, increasing the capacity and speed using new modulation techniques...

, OFDMA is used for the downlink. By contrast, IFDMA is being considered for the uplink since OFDMA contributes more to the PAPR
Crest factor
The crest factor or peak-to-average ratio or peak-to-average power ratio is a measurement of a waveform, calculated from the peak amplitude of the waveform divided by the RMS value of the waveform.C =...

 related issues and results in nonlinear operation of amplifiers. IFDMA provides less power fluctuation and thus avoids amplifier issues. Similarly, MC-CDMA is in the proposal for the IEEE 802.20 standard. These access schemes offer the same efficiencies as older technologies like CDMA. Apart from this, scalability and higher data rates can be achieved.

The other important advantage of the above mentioned access techniques is that they require less complexity for equalization at the receiver. This is an added advantage especially in the MIMO
MIMO
In radio, multiple-input and multiple-output, or MIMO , is the use of multiple antennas at both the transmitter and receiver to improve communication performance. It is one of several forms of smart antenna technology...

 environments since the spatial multiplexing
Spatial multiplexing
Spatial multiplexing is a transmission technique in MIMO wireless communication to transmit independent and separately encoded data signals, so-called streams, from each of the multiple transmit antennas...

 transmission of MIMO systems inherently requires high complexity equalization at the receiver.

In addition to improvements in these multiplexing systems, improved modulation
Modulation
In electronics and telecommunications, modulation is the process of varying one or more properties of a high-frequency periodic waveform, called the carrier signal, with a modulating signal which typically contains information to be transmitted...

 techniques are being used. Whereas earlier standards largely used Phase-shift keying
Phase-shift keying
Phase-shift keying is a digital modulation scheme that conveys data by changing, or modulating, the phase of a reference signal ....

, more efficient systems such as 64QAM are being proposed for use with the 3GPP Long Term Evolution
3GPP Long Term Evolution
3GPP Long Term Evolution, usually referred to as LTE, is a standard for wireless communication of high-speed data for mobile phones and data terminals. It is based on the GSM/EDGE and UMTS/HSPA network technologies, increasing the capacity and speed using new modulation techniques...

 standards.

IPv6 support



Unlike 3G, which is based on two parallel infrastructures consisting of circuit switched and packet switched network nodes respectively, 4G will be based on packet switching only. This will require low-latency
Lag
Lag is a common word meaning to fail to keep up or to fall behind. In real-time applications, the term is used when the application fails to respond in a timely fashion to inputs...

 data transmission.

By the time that 4G was deployed, the process of IPv4 address exhaustion was expected to be in its final stages. Therefore, in the context of 4G, IPv6
IPv6
Internet Protocol version 6 is a version of the Internet Protocol . It is designed to succeed the Internet Protocol version 4...

 support is essential in order to support a large number of wireless-enabled devices. By increasing the number of IP address
IP address
An Internet Protocol address is a numerical label assigned to each device participating in a computer network that uses the Internet Protocol for communication. An IP address serves two principal functions: host or network interface identification and location addressing...

es, IPv6 removes the need for network address translation
Network address translation
In computer networking, network address translation is the process of modifying IP address information in IP packet headers while in transit across a traffic routing device....

 (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
IPv4
Internet Protocol version 4 is the fourth revision in the development of the Internet Protocol and the first version of the protocol to be widely deployed. Together with IPv6, it is at the core of standards-based internetworking methods of the Internet...

 networks.

, Verizon has posted specifications that require any 4G devices on its network to support IPv6.

Advanced antenna systems


The performance of radio communications depends on an antenna system, termed smart
Smart antenna
Smart antennas are antenna arrays with smart signal processing algorithms used to identify spatial signal signature such as the direction of arrival of the signal, and use it to calculate beamforming vectors, to track and locate the antenna beam on the mobile/target...

 or intelligent antenna. Recently, multiple antenna technologies are emerging to achieve the goal of 4G systems such as high rate, high reliability, and long range communications. In the early 1990s, to cater for the growing data rate needs of data communication, many transmission schemes were proposed. One technology, spatial multiplexing
Spatial multiplexing
Spatial multiplexing is a transmission technique in MIMO wireless communication to transmit independent and separately encoded data signals, so-called streams, from each of the multiple transmit antennas...

, gained importance for its bandwidth conservation and power efficiency. Spatial multiplexing involves deploying multiple antennas at the transmitter and at the receiver. Independent streams can then be transmitted simultaneously from all the antennas. This technology, called MIMO
MIMO
In radio, multiple-input and multiple-output, or MIMO , is the use of multiple antennas at both the transmitter and receiver to improve communication performance. It is one of several forms of smart antenna technology...

 (as a branch of intelligent antenna), multiplies the base data rate by (the smaller of) the number of transmit antennas or the number of receive antennas. Apart from this, 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 transmitter. The other category is closed-loop multiple antenna technologies, which require channel knowledge at the transmitter.

Software-defined radio (SDR)


SDR
Software-defined radio
A software-defined radio system, or SDR, is a radio communication system where components that have been typically implemented in hardware are instead implemented by means of software on a personal computer or embedded computing devices...

 is one form of open wireless architecture (OWA). Since 4G is a collection of wireless standards, the final form of a 4G device will constitute various standards. This can be efficiently realized using SDR technology, which is categorized to the area of the radio convergence.

History of 4G and pre-4G technologies


As of August 2011, there are no 4G networks that fulfil the International Telecommunication Union's criteria of being able to achieve 1Gbit/s while stationary.

However in December 2010, the ITU recognized that current versions of LTE, WiMax and other evolved 3G technologies that do not fulfill "IMT-Advanced" requirements could nevertheless be considered "4G", provided they represent forerunners to IMT-Advanced and "a substantial level of improvement in performance and capabilities with respect to the initial third generation systems now deployed."
  • In 2002, the strategic vision for 4G—which ITU
    Itu
    Itu is an old and historic municipality in the state of São Paulo in Brazil. The population in 2009 was 157,384 and the area is 641.68 km². The elevation is 583 m. This place name comes from the Tupi language, meaning big waterfall. Itu is linked with the highway numbered the SP-75 and are flowed...

     designated as IMT-Advanced—was laid out.
  • In 2005, OFDMA
    OFDMA
    Orthogonal Frequency-Division Multiple Access is a multi-user version of the popular Orthogonal frequency-division multiplexing digital modulation scheme. Multiple access is achieved in OFDMA by assigning subsets of subcarriers to individual users as shown in the illustration below...

     transmission technology is chosen as candidate for the HSOPA
    HSOPA
    e-UTRAN or eUTRAN is the air interface of 3GPP's Long Term Evolution upgrade path for mobile networks. It is the abbreviation for evolved UMTS Terrestrial Radio Access Network, also referred to as the 3GPP work item on the Long Term Evolution also known as the Evolved Universal Terrestrial Radio...

     downlink, later renamed 3GPP Long Term Evolution (LTE) air interface E-UTRA
    E-UTRA
    e-UTRAN or eUTRAN is the air interface of 3GPP's Long Term Evolution upgrade path for mobile networks. It is the abbreviation for evolved UMTS Terrestrial Radio Access Network, also referred to as the 3GPP work item on the Long Term Evolution also known as the Evolved Universal Terrestrial Radio...

    .
  • In November 2005, KT demonstrated mobile WiMAX service in Busan, South Korea.
  • In June 2006, KT started the world's first commercial mobile WiMAX service in Seoul, South Korea.
  • In mid-2006, Sprint Nextel
    Sprint Nextel
    Sprint Nextel Corporation is an American telecommunications company based in Overland Park, Kansas. The company owns and operates Sprint, the third largest wireless telecommunications network in the United States, with 53.4 million customers, behind Verizon Wireless and AT&T Mobility...

     announced that it would invest about US$5 billion in a WiMAX
    WiMAX
    WiMAX is a communication technology for wirelessly delivering high-speed Internet service to large geographical areas. The 2005 WiMAX revision provided bit rates up to 40 Mbit/s with the 2011 update up to 1 Gbit/s for fixed stations...

     technology buildout over the next few years ($ in real terms). Since that time Sprint has faced many setbacks, that have resulted in steep quarterly losses. On May 7, 2008, Sprint
    Sprint Nextel
    Sprint Nextel Corporation is an American telecommunications company based in Overland Park, Kansas. The company owns and operates Sprint, the third largest wireless telecommunications network in the United States, with 53.4 million customers, behind Verizon Wireless and AT&T Mobility...

    , Imagine
    Imagine Communications
    Imagine Communications is an Irish internet service provider and telecommunications operator, who provide WiMAX, wireless broadband and resell Eircom telecommunications wholesale packages...

    , Google
    Google
    Google Inc. is an American multinational public corporation invested in Internet search, cloud computing, and advertising technologies. Google hosts and develops a number of Internet-based services and products, and generates profit primarily from advertising through its AdWords program...

    , Intel, Comcast
    Comcast
    Comcast Corporation is the largest cable operator, home Internet service provider, and fourth largest home telephone service provider in the United States, providing cable television, broadband Internet, and telephone service to both residential and commercial customers in 39 states and the...

    , Bright House
    Bright House Networks
    Bright House Networks is a cable television company, the seventh largest cable operator and the sixth largest traditional multiple system operator in the United States owned by Advance/Newhouse, headquartered in Syracuse, New York...

    , and Time Warner
    Time Warner
    Time Warner is one of the world's largest media companies, headquartered in the Time Warner Center in New York City. Formerly two separate companies, Warner Communications, Inc...

     announced a pooling of an average of 120 MHz of spectrum; Sprint merged its Xohm
    Xohm
    XOHM was the brand name Sprint Nextel Corporation was using to promote its WiMAX services, currently labelled by Sprint Nextel simply as 4G. Sprint was the first service provider in the United States, with its partner Clearwire, to announce the building of a mobile WiMAX network...

     WiMAX division with Clearwire
    Clearwire
    Clearwire Corporation is a wireless internet service provider serving markets in the United States, Belgium, and Spain...

     to form a company which will take the name "Clear".
  • In February 2007, the Japanese company NTT DoCoMo
    NTT DoCoMo
    is the predominant mobile phone operator in Japan. The name is officially an abbreviation of the phrase, "do communications over the mobile network", and is also from a compound word dokomo, meaning "everywhere" in Japanese. Docomo provides phone, video phone , i-mode , and mail services...

     tested a 4G communication system prototype with 4x4 MIMO
    MIMO
    In radio, multiple-input and multiple-output, or MIMO , is the use of multiple antennas at both the transmitter and receiver to improve communication performance. It is one of several forms of smart antenna technology...

     called VSF-OFCDM at 100 Mbit/s while moving, and 1 Gbit/s while stationary. NTT DoCoMo completed a trial in which they reached a maximum packet transmission rate of approximately 5 Gbit/s in the downlink with 12x12 MIMO using a 100 MHz frequency bandwidth while moving at 10 km/h, and is planning on releasing the first commercial network in 2010.
  • In September 2007, NTT Docomo demonstrated e-UTRA data rates of 200 Mbit/s with power consumption below 100 mW during the test.
  • In January 2008, a U.S. Federal Communications Commission
    Federal Communications Commission
    The Federal Communications Commission is an independent agency of the United States government, created, Congressional statute , and with the majority of its commissioners appointed by the current President. The FCC works towards six goals in the areas of broadband, competition, the spectrum, the...

     (FCC) spectrum auction
    Spectrum auction
    A spectrum auction is a process whereby a government uses an auction system to sell the rights to transmit signals over specific bands of the electromagnetic spectrum and to assign scarce spectrum resources. Depending on the specific auction format used, a spectrum auction can last from a single...

     for the 700 MHz former analog TV frequencies began. As a result, the biggest share of the spectrum went to Verizon Wireless and the next biggest to AT&T. Both of these companies have stated their intention of supporting LTE
    3GPP Long Term Evolution
    3GPP Long Term Evolution, usually referred to as LTE, is a standard for wireless communication of high-speed data for mobile phones and data terminals. It is based on the GSM/EDGE and UMTS/HSPA network technologies, increasing the capacity and speed using new modulation techniques...

    .
  • In January 2008, EU commissioner Viviane Reding
    Viviane Reding
    Viviane Reding is a Luxembourgian politician, currently serving as European Commissioner for Justice, Fundamental Rights and Citizenship. Before starting a professional career as a journalist for the leading newspaper in Luxembourg, the Luxemburger Wort, she obtained a doctorate in human sciences...

     suggested re-allocation of 500–800 MHz spectrum for wireless communication, including WiMAX.
  • On 15 February 2008 - Skyworks Solutions released a front-end module for e-UTRAN.
  • In 2008, ITU-R
    ITU-R
    The ITU Radiocommunication Sector is one of the three sectors of the International Telecommunication Union and is responsible for radio communication....

     established the detailed performance requirements of IMT-Advanced, by issuing a Circular Letter calling for candidate Radio Access Technologies (RATs) for IMT-Advanced.
  • In April 2008, just after receiving the circular letter, the 3GPP organized a workshop on IMT-Advanced where it was decided that LTE Advanced, an evolution of current LTE standard, will meet or even exceed IMT-Advanced requirements following the ITU-R agenda.
  • In April 2008, LG and Nortel demonstrated e-UTRA data rates of 50 Mbit/s while travelling at 110 km/h.
  • On 12 November 2008, HTC
    High Tech Computer
    HTC Corporation , formerly High Tech Computer Corporation, is a Taiwanese manufacturer of smartphones. The company initially made smartphones based mostly on Microsoft's Windows Mobile operating system software, but in 2009 it began to shift its core focus away from Windows Mobile devices to...

     announced the first WiMAX-enabled mobile phone, the Max 4G
  • In December 2008, San Miguel Corporation
    San Miguel Corporation
    Established in 1890 as a brewery, San Miguel Corporation is Southeast Asia's largest publicly listed food, beverage and packaging company with over 17,000 employees in over 100 major facilities throughout the Asia-Pacific....

    , Asia's largest food and beverage conglomerate, has signed a memorandum of understanding with Qatar Telecom QSC (Qtel
    Qtel
    Qtel used to be the exclusive telecommunications provider in Qatar and is one of the largest public companies in Qatar with about 2000 employees. It was successfully launched on the Doha Securities Market in 1998 and listed on the London Stock Exchange in 1999, the Bahrain Stock Exchange in 2001...

    ) to build wireless broadband and mobile communications projects in the Philippines. The joint-venture formed wi-tribe Philippines, which offers 4G in the country. Around the same time Globe Telecom
    Globe Telecom
    Globe Telecom , commonly known as Globe, is a telecommunications company in the Philippines. Globe provides mobile, fixed line, and broadband Internet services.- History :In 1928, Congress passed Act No...

     rolled out the first WiMAX service in the Philippines.
  • On 3 March 2009, Lithuania's LRTC announcing the first operational "4G" mobile WiMAX network in Baltic states.
  • In December 2009, Sprint began advertising "4G" service in selected cities in the United States, despite average download speeds of only 3–6 Mbit/s with peak speeds of 10 Mbit/s (not available in all markets).
  • On 14 December 2009, the first commercial LTE deployment was in the Scandinavian capitals Stockholm
    Stockholm
    Stockholm is the capital and the largest city of Sweden and constitutes the most populated urban area in Scandinavia. Stockholm is the most populous city in Sweden, with a population of 851,155 in the municipality , 1.37 million in the urban area , and around 2.1 million in the metropolitan area...

     and Oslo
    Oslo
    Oslo is a municipality, as well as the capital and most populous city in Norway. As a municipality , it was established on 1 January 1838. Founded around 1048 by King Harald III of Norway, the city was largely destroyed by fire in 1624. The city was moved under the reign of Denmark–Norway's King...

     by the Swedish-Finnish network operator TeliaSonera
    TeliaSonera
    TeliaSonera AB is the dominant telephone company and mobile network operator in Sweden and Finland. The company has operations in other countries in Northern, Eastern Europe, Central Asia and Spain, with a total of 150 million mobile customers...

     and its Norwegian brandname NetCom (Norway)
    NetCom (Norway)
    NetCom is a Norwegian mobile phone operator. Founded in 1993, it is the second largest mobile phone operator in Norway. The company has about 1.2 million subscribers, and the company headquarters are located in Nydalen in Oslo. It is owned by the Swedish and Finnish company TeliaSonera...

    . TeliaSonera branded the network "4G". The modem devices on offer were manufactured by Samsung
    Samsung
    The Samsung Group is a South Korean multinational conglomerate corporation headquartered in Samsung Town, Seoul, South Korea...

     (dongle GT-B3710), and the network infrastructure created by Huawei
    Huawei
    Huawei is a Chinese multinational networking and telecommunications equipment and services company headquartered in Shenzhen, Guangdong, China...

     (in Oslo) and Ericsson
    Ericsson
    Ericsson , one of Sweden's largest companies, is a provider of telecommunication and data communication systems, and related services, covering a range of technologies, including especially mobile networks...

     (in Stockholm). TeliaSonera plans to roll out nationwide LTE across Sweden, Norway and Finland. TeliaSonera used spectral bandwidth of 10 MHz, and single-in-single-out, which should provide physical layer net bitrates of up to 50 Mbit/s downlink and 25 Mbit/s in the uplink. Introductory tests showed a TCP
    Transmission Control Protocol
    The Transmission Control Protocol is one of the core protocols of the Internet Protocol Suite. TCP is one of the two original components of the suite, complementing the Internet Protocol , and therefore the entire suite is commonly referred to as TCP/IP...

     throughput
    Throughput
    In communication networks, such as Ethernet or packet radio, throughput or network throughput is the average rate of successful message delivery over a communication channel. This data may be delivered over a physical or logical link, or pass through a certain network node...

     of 42.8 Mbit/s downlink and 5.3 Mbit/s uplink in Stockholm.
  • On 25 February 2010, Estonia's EMT
    EMT (mobile operator)
    AS EMT is Estonia's and one of the largest Baltic's mobile operator. Founded on 28 April 1991 as an Estonian Swedish-Finnish joint company.Headquarter in Tallinn. Traded on NASDAQ OMX stock exchanges.- External links :* * *...

     opened LTE "4G" network working in test regime.
  • On 4 June 2010, Sprint Nextel
    Sprint Nextel
    Sprint Nextel Corporation is an American telecommunications company based in Overland Park, Kansas. The company owns and operates Sprint, the third largest wireless telecommunications network in the United States, with 53.4 million customers, behind Verizon Wireless and AT&T Mobility...

     released the first WiMAX smartphone in the US, the HTC Evo 4G
    HTC Evo 4G
    The HTC Evo 4G is a smartphone developed by HTC Corporation and marketed as Sprint's flagship Android smartphone, running on its WiMAX network...

    .
  • In July 2010, Uzbekistan
    Uzbekistan
    Uzbekistan , officially the Republic of Uzbekistan is a doubly landlocked country in Central Asia and one of the six independent Turkic states. It shares borders with Kazakhstan to the west and to the north, Kyrgyzstan and Tajikistan to the east, and Afghanistan and Turkmenistan to the south....

    's MTS
    Mobile TeleSystems
    MTS is the largest mobile operator in Russia and CIS with over 102,4 million subscribers as of 31 December 2009.Having started in the Moscow license zone in 1994, МТS in 1997 received licenses for further areas and began expansion, later entering other countries of the CIS...

     deployed LTE in Tashkent
    Tashkent
    Tashkent is the capital of Uzbekistan and of the Tashkent Province. The officially registered population of the city in 2008 was about 2.2 million. Unofficial sources estimate the actual population may be as much as 4.45 million.-Early Islamic History:...

    .
  • On 25 August 2010, Latvia
    Latvia
    Latvia , officially the Republic of Latvia , is a country in the Baltic region of Northern Europe. It is bordered to the north by Estonia , to the south by Lithuania , to the east by the Russian Federation , to the southeast by Belarus and shares maritime borders to the west with Sweden...

    's LMT
    Latvian Mobile Telephone
    Latvian Mobile Telephone is a mobile GSM/UMTS operator in Latvia.- History :LMT has operated on the mobile market since 1992 and is the first mobile network operator in the country. The service was established as an operator of the NMT system. Within a couple of years of starting, the company has...

     opened LTE "4G" network working in test regime 50% of territory.
  • On 6 December 2010, at the ITU World Radiocommunication Seminar 2010, the ITU
    Itu
    Itu is an old and historic municipality in the state of São Paulo in Brazil. The population in 2009 was 157,384 and the area is 641.68 km². The elevation is 583 m. This place name comes from the Tupi language, meaning big waterfall. Itu is linked with the highway numbered the SP-75 and are flowed...

     stated that LTE
    3GPP Long Term Evolution
    3GPP Long Term Evolution, usually referred to as LTE, is a standard for wireless communication of high-speed data for mobile phones and data terminals. It is based on the GSM/EDGE and UMTS/HSPA network technologies, increasing the capacity and speed using new modulation techniques...

    , WiMax
    WiMAX
    WiMAX is a communication technology for wirelessly delivering high-speed Internet service to large geographical areas. The 2005 WiMAX revision provided bit rates up to 40 Mbit/s with the 2011 update up to 1 Gbit/s for fixed stations...

     and similar "evolved 3G technologies" could be considered "4G".
  • On 12 December 2010, VivaCell-MTS launches in Armenia
    Armenia
    Armenia , officially the Republic of Armenia , is a landlocked mountainous country in the Caucasus region of Eurasia...

     4G/LTE commercial test network with a live demo conducted in Yerevan
    Yerevan
    Yerevan is the capital and largest city of Armenia and one of the world's oldest continuously-inhabited cities. Situated along the Hrazdan River, Yerevan is the administrative, cultural, and industrial center of the country...

    .
  • On 28 April 2011, Lithuania
    Lithuania
    Lithuania , officially the Republic of Lithuania is a country in Northern Europe, the biggest of the three Baltic states. It is situated along the southeastern shore of the Baltic Sea, whereby to the west lie Sweden and Denmark...

    's Omnitel
    Omnitel
    Omnitel is one of the largest telecommunication companies in the Baltics, member of TeliaSonera group. It provides services of carrying and packaging of voice, images, data, information, transactions and entertainment....

     opened LTE "4G" network working in 5 biggest cities.
  • In September 2011, All three Saudi telecom giants STC
    Saudi Telecom Company
    Saudi Telecom Group, STC is a Saudi Arabia-based telecommunications company that offers landline, mobile and Internet services.-Background:...

    , Mobily
    Mobily
    Mobily is the trade name of Saudi Arabia's second Telecommunications company, Etihad-Etisalat consortium . The company, as the winning bidder for Saudi Arabia's second GSM licence, provides mobile telecom services nationwide, breaking Saudi Telecom's monopoly in the wireless business...

     and Zain
    Zain
    -People:*as a given name in general , orwith a first name of Zain*Zain Abbas , a Pakistan-born cricketer*Zain Amat , a Singaporean trapshooter*Zain Awan , an India-born Arab TV journalist...

     announced that they will offer 4G LTE for high speed USB sticks for mobile computers, with further development for telephones by 2013.
  • In 2011, Argentina
    Argentina
    Argentina , officially the Argentine Republic , is the second largest country in South America by land area, after Brazil. It is constituted as a federation of 23 provinces and an autonomous city, Buenos Aires...

    ´s Claro
    Claro
    Claro or CLARO may refer to:* Claro, Switzerland, in the canton of Ticino* Claro Americas, a mobile and fixed voice and data comunications company*:Claro Argentina, Paraguay and Uruguay*:Claro El Salvador*:Claro Guatemala*:Claro Jamaica...

     launch 4G HSPA+ network in the country.

Deployment plans


In May 2005, Digiweb
Digiweb
Digiweb is a telecommunications company in Ireland, supplying business and consumer broadband and web hosting.Digiweb is 100% Irish owned and run, and is headquartered in Dundalk, County Louth with its technical, installation and sales offices in Dublin....

, an Irish fixed and wireless broadband company, announced that they had received a mobile communications license from the Irish Telecoms regulator, ComReg. This service will be issued the mobile code 088 in Ireland and will be used for the provision of 4G Mobile communications. Digiweb launched a mobile broadband network using FLASH-OFDM technology at 872 MHz.

On September 20, 2007, Verizon Wireless
Verizon Wireless
Cellco Partnership, doing business as Verizon Wireless, is one of the largest mobile network operators in the United States. The network has 107.7 million subscribers as of 2011, making it the largest wireless service provider in America....

 announced plans for a joint effort with the Vodafone Group to transition its networks to the 4G standard LTE. On December 9, 2008, Verizon Wireless announced their intentions to build and begin to roll out an LTE network by the end of 2009. Since then, Verizon Wireless has said that they will start their rollout by the end of 2010.

On July 7, 2008, South Korea
South Korea
The Republic of Korea , , is a sovereign state in East Asia, located on the southern portion of the Korean Peninsula. It is neighbored by the People's Republic of China to the west, Japan to the east, North Korea to the north, and the East China Sea and Republic of China to the south...

 announced plans to spend 60 billion won
South Korean won
The won is the currency of South Korea. A single won is divided into 100 jeon, the monetary subunit. The jeon is no longer used for everyday transactions, and appears only in foreign exchange rates...

, or US$58,000,000, on developing 4G and even 5G technologies, with the goal of having the highest mobile phone market share by 2012, and the hope of an international standard.

Telus
TELUS
Telus is a national telecommunications company in Canada that provides a wide range of telecommunications products and services including internet access, voice, entertainment, video, and satellite television. The company is based in Burnaby, British Columbia, part of Greater Vancouver...

 and Bell Canada
Bell Canada
Bell Canada is a major Canadian telecommunications company. Including its subsidiaries such as Bell Aliant, Northwestel, Télébec, and NorthernTel, it is the incumbent local exchange carrier for telephone and DSL Internet services in most of Canada east of Manitoba and in the northern territories,...

, the major Canadian cdmaOne and EV-DO carriers, have announced that they will be cooperating towards building a fourth generation (4G) LTE wireless broadband network in Canada. As a transitional measure, they are implementing 3G UMTS that went live in November 2009.

Sprint Nextel
Sprint Nextel
Sprint Nextel Corporation is an American telecommunications company based in Overland Park, Kansas. The company owns and operates Sprint, the third largest wireless telecommunications network in the United States, with 53.4 million customers, behind Verizon Wireless and AT&T Mobility...

 offers a 3G/4G connection plan, currently available in select cities in the United States. It delivers rates up to 10 Mbit/s. Sprint has announced that they will launch a LTE network in early 2012.

In the United Kingdom
United Kingdom
The United Kingdom of Great Britain and Northern IrelandIn the United Kingdom and Dependencies, other languages have been officially recognised as legitimate autochthonous languages under the European Charter for Regional or Minority Languages...

, Telefónica O2 is to use Slough
Slough
Slough is a borough and unitary authority within the ceremonial county of Royal Berkshire, England. The town straddles the A4 Bath Road and the Great Western Main Line, west of central London...

 as a guinea pig in testing the 4G network and has called upon Huawei
Huawei
Huawei is a Chinese multinational networking and telecommunications equipment and services company headquartered in Shenzhen, Guangdong, China...

 to install LTE technology in six masts across the town to allow people to talk to each other via HD video conferencing and play PlayStation games while on the move.

Verizon Wireless
Verizon Wireless
Cellco Partnership, doing business as Verizon Wireless, is one of the largest mobile network operators in the United States. The network has 107.7 million subscribers as of 2011, making it the largest wireless service provider in America....

 has announced that it plans to augment its CDMA2000-based EV-DO 3G network in the United States with LTE, and is supposed to complete a rollout of 175 cities by the end of 2011, two thirds of the US population by mid-2012, and cover the existing 3G network by the end of 2013. AT&T, along with Verizon Wireless, has chosen to migrate toward LTE from 2G/GSM and 3G/HSPA by 2011.

Sprint Nextel
Sprint Nextel
Sprint Nextel Corporation is an American telecommunications company based in Overland Park, Kansas. The company owns and operates Sprint, the third largest wireless telecommunications network in the United States, with 53.4 million customers, behind Verizon Wireless and AT&T Mobility...

 has deployed WiMAX technology which it has labeled 4G as of October 2008. It is currently deploying to additional markets and is the first US carrier to offer a WiMAX phone.

The U.S. FCC is exploring the possibility of deployment and operation of a nationwide 4G public safety network which would allow first responders to seamlessly communicate between agencies and across geographies, regardless of devices. In June 2010 the FCC released a comprehensive white paper which indicates that the 10 MHz of dedicated spectrum currently allocated from the 1700 MHz spectrum for public safety will provide adequate capacity and performance necessary for normal communications as well as serious emergency situations.

TeliaSonera
TeliaSonera
TeliaSonera AB is the dominant telephone company and mobile network operator in Sweden and Finland. The company has operations in other countries in Northern, Eastern Europe, Central Asia and Spain, with a total of 150 million mobile customers...

 started deploying LTE (branded "4G") in Stockholm and Oslo November 2009 (as seen above), and in several Swedish, Norwegian, and Finnish cities during 2010. In June 2010, Swedish television companies used 4G to broadcast live television from the Swedish Crown Princess' Royal Wedding
Wedding of Victoria, Crown Princess of Sweden, and Daniel Westling
The royal wedding between Victoria, Crown Princess of Sweden, and Daniel Westling took place on 2010 in Stockholm Cathedral. It has been described as "Europe's biggest royal wedding since the Prince of Wales married Lady Diana Spencer in 1981." Westling's style and title after the marriage is now...

.

Safaricom, a telecommunication company in East& Central Africa, began its setup of a 4G network in October 2010 after the now retired& Kenya Tourist Board Chairman, Michael Joseph, regarded their 3G network as a white elephant i.e. it failed to perform to expectations. Huawei was given the contract the network is set to go fully commercial by the end of Q1 of 2011

Telstra
Telstra
Telstra Corporation Limited is an Australian telecommunications and media company, building and operating telecommunications networks and marketing voice, mobile, internet access and pay television products and services....

 announced on 15 February 2011, that it intends to upgrade its current Next G network to 4G with Long Term Evolution (LTE) technology in the central business districts of all Australian capital cities and selected regional centers by the end of 2011.

Sri Lanka Telecom Mobitel and Dialog Axiata announced that first time in South Asia Sri Lanka have successfully tested and demonstrated 4G technology on 6th of May 2011(Sri Lanka Telecom Mobitel) and 7th of May 2011(Dialog Axiata) and began the setup of their 4G Networks in Sri Lanka.

On May 2011, Brazil
Brazil
Brazil , officially the Federative Republic of Brazil , is the largest country in South America. It is the world's fifth largest country, both by geographical area and by population with over 192 million people...

's Communication Ministry announced that the 12 host cities for the 2014 FIFA World Cup
2014 FIFA World Cup
The 2014 FIFA World Cup will be the 20th FIFA World Cup, an international association football tournament that will take place in Brazil from 12 June to 13 July 2014....

 to be held there will be the first to have their networks upgraded to 4G. Mobitel was able to reach 96mbps of speed while Dialog Axiata reached 128mbps on their demonstration.

In mid September 2011, Mobily of Saudi Arabia
Saudi Arabia
The Kingdom of Saudi Arabia , commonly known in British English as Saudi Arabia and in Arabic as as-Sa‘ūdiyyah , is the largest state in Western Asia by land area, constituting the bulk of the Arabian Peninsula, and the second-largest in the Arab World...

, announced their 4G LTE networks to be ready after months of testing and evaluations.

On September 2011, UAE's Etisalat
Etisalat
Emirates Telecommunications Corporation, branded trade name Etisalat is a UAE based telecommunications services provider, currently operating in 18 countries across Asia, the Middle East and Africa...

 announced commercial launch of 4G LTE services covering over 70% of country's urban areas.

India
India
India , officially the Republic of India , is a country in South Asia. It is the seventh-largest country by geographical area, the second-most populous country with over 1.2 billion people, and the most populous democracy in the world...

 is expected to see launch of 4G services using TD-LTE
Time-Division Long-Term Evolution
Time-Division Long-Term Evolution , also referred to as Long-Term Evolution Time-Division Duplex , is China's home-grown 4-G mobile-telecommunications technology and standard co-developed, since late 2007, by Datang Telecom, China Mobile, Huawei, ZTE, Nokia Siemens Networks, Alcatel Shanghai Bell,...

 technology in January 2012. The services will be launched by Augere
Augere
Augere is a wireless broadband business founded in 2007. It is headed by the former CEO of Orange, Sanjiv Ahuja. It has a mission to provide 'broadband for all' and is working to bring available, affordable and accessible broadband internet services to under-served communities worldwideAugere has...

, a UK based company, in Madhya Pradesh
Madhya Pradesh
Madhya Pradesh , often called the Heart of India, is a state in central India. Its capital is Bhopal and Indore is the largest city....

 and Chhattisgarh
Chhattisgarh
Chhattisgarh is a state in Central India, formed when the 16 Chhattisgarhi-speaking South-Eastern districts of Madhya Pradesh gained separate statehood on 1 November 2000....

 under the Zoosh brand name.

Beyond 4G research



A major issue in 4G systems is to make the high bit rates available in a larger portion of the cell, especially to users in an exposed position in between several base stations. In current research, this issue is addressed by macro-diversity techniques, also known as group cooperative relay
Cooperative diversity
Cooperative diversity is a cooperative multiple antenna technique for improving or maximising total network channel capacities for any given set of bandwidths which exploits user diversity by decoding the combined signal of the relayed signal and the direct signal in wireless multihop networks...

, and also by Beam-Division Multiple Access (BDMA).

Pervasive networks are an amorphous and at present entirely hypothetical concept where the user can be simultaneously connected to several wireless access technologies and can seamlessly move between them (See vertical handoff
Vertical handoff
Vertical handover or vertical handoff refers to a network node changing the type of connectivity it uses to access a supporting infrastructure, usually to support node mobility. For example, a suitably equipped laptop might be able to use both a high speed wireless LAN and a cellular technology for...

, IEEE 802.21
IEEE 802.21
802.21 is an IEEE standard published in 2008. The standard supports algorithms enabling seamless handover between networks of the same type as well as handover between different network types also called Media independent handover or vertical handover...

). These access technologies can be Wi-Fi
Wi-Fi
Wi-Fi or Wifi, is a mechanism for wirelessly connecting electronic devices. A device enabled with Wi-Fi, such as a personal computer, video game console, smartphone, or digital audio player, can connect to the Internet via a wireless network access point. An access point has a range of about 20...

, UMTS
Universal Mobile Telecommunications System
Universal Mobile Telecommunications System is a third generation mobile cellular technology for networks based on the GSM standard. Developed by the 3GPP , UMTS is a component of the International Telecommunications Union IMT-2000 standard set and compares with the CDMA2000 standard set for...

, EDGE
Enhanced Data Rates for GSM Evolution
Enhanced Data rates for GSM Evolution is a digital mobile phone technology that allows improved data transmission rates as a backward-compatible extension of GSM...

, or any other future access technology. Included in this concept is also smart-radio (also known as cognitive radio
Cognitive radio
A cognitive radio is a kind of two-way radio that automatically changes its transmission or reception parameters, in a way where the entire wireless communication network -- of which it is a node -- communicates efficiently, while avoiding interference with licensed or licensed exempt users...

) technology to efficiently manage spectrum use and transmission power as well as the use of mesh routing
Mesh networking
Mesh networking is a type of networking where each node must not only capture and disseminate its own data, but also serve as a relay for other nodes, that is, it must collaborate to propagate the data in the network....

 protocols to create a pervasive network.

External links