In
telecommunications
Telecommunication, often used in its plural form or abbreviated as telecom, is the transmission of information over a distance using electronic means, typically through cables, radio waves, or other communication technologies. These means of ...
, long-term evolution (LTE) is a
standard for
wireless broadband communication for
cellular mobile devices and data terminals. It is considered to be a "transitional"
4G technology,
and is therefore also referred to as 3.95G as a step above
3G.
LTE is based on the
2G GSM
The Global System for Mobile Communications (GSM) is a family of standards to describe the protocols for second-generation (2G) digital cellular networks, as used by mobile devices such as mobile phones and Mobile broadband modem, mobile broadba ...
/
EDGE and 3G
UMTS
The Universal Mobile Telecommunications System (UMTS) is a 3G mobile cellular system for networks based on the GSM standard. UMTS uses Wideband Code Division Multiple Access, wideband code-division multiple access (W-CDMA) radio access technolog ...
/
HSPA standards. It improves on those standards' capacity and speed by using a different radio interface and core network improvements. LTE is the upgrade path for carriers with both GSM/UMTS networks and
CDMA2000
CDMA2000 (also known as C2K or IMT Multi‑Carrier (IMT‑MC)) is a family of 3G mobile technology standards for sending voice, data, and signaling data between mobile phones and cell sites. It is developed by 3GPP2 as a backwards-compatib ...
networks. LTE has been succeeded by
LTE Advanced, which is officially defined as a "true" 4G technology
and also named "LTE+".
Terminology
The standard is developed by the
3GPP (3rd Generation Partnership Project) and is specified in its Release 8 document series, with minor enhancements described in Release 9. LTE is also called 3.95G and has been marketed as 4G LTE and Advanced 4G; but the original version did not meet the technical criteria of a
4G wireless service, as specified in the 3GPP Release 8 and 9 document series for
LTE Advanced. The requirements were set forth by the
ITU-R organisation in the
IMT Advanced specification; but, because of market pressure and the significant advances that
WiMAX,
Evolved High Speed Packet Access, and LTE bring to the original 3G technologies, ITU-R later decided that LTE and the aforementioned technologies can be called 4G technologies. The LTE Advanced standard formally satisfies the ITU-R requirements for being considered IMT-Advanced. To differentiate LTE Advanced and
WiMAX-Advanced from current 4G technologies, ITU has defined the latter as "True 4G".
Overview

LTE stands for Long-Term Evolution and is a registered trademark owned by
ETSI
The European Telecommunications Standards Institute (ETSI) is an independent, not-for-profit, standardization organization operating in the field of Information and communications technology, information and communications. ETSI supports the de ...
(European Telecommunications Standards Institute) for the wireless
data communication
Data communication, including data transmission and data reception, is the transfer of data, transmitted and received over a point-to-point or point-to-multipoint communication channel. Examples of such channels are copper wires, optic ...
s technology and development of the GSM/UMTS standards. However, other nations and companies do play an active role in the LTE project. The goal of LTE was to increase the capacity and speed of wireless data networks using new
DSP (digital signal processing) techniques and modulations that were developed around the turn of the millennium. A further goal was the redesign and simplification of the
network architecture to an
IP-based system with significantly reduced transfer
latency compared with the
3G architecture. The LTE wireless interface is incompatible with
2G and 3G networks so it must be operated on a separate
radio spectrum
The radio spectrum is the part of the electromagnetic spectrum with frequencies from 3 Hz to 3,000 GHz (3 THz). Electromagnetic waves in this frequency range, called radio waves, are widely used in modern technology, particula ...
.
The idea of LTE was first proposed in 1998, with the use of the
COFDM
In telecommunications, orthogonal frequency-division multiplexing (OFDM) is a type of digital transmission used in digital modulation for encoding digital (binary) data on multiple Carrier wave, carrier frequencies. OFDM has developed into a popul ...
radio access technique to replace the
CDMA and studying its Terrestrial use in the L band at 1428 MHz (TE)
In 2004 by Japan's
NTT Docomo, with studies on the standard officially commenced in 2005.
In May 2007, the LTE/
SAE Trial Initiative (LSTI) alliance was founded as a global collaboration between vendors and operators with the goal of verifying and promoting the new standard in order to ensure the global introduction of the technology as quickly as possible.
The LTE standard was finalized in December 2008, and the first publicly available LTE service was launched by
TeliaSonera in
Oslo
Oslo ( or ; ) is the capital and most populous city of Norway. It constitutes both a county and a municipality. The municipality of Oslo had a population of in 2022, while the city's greater urban area had a population of 1,064,235 in 2022 ...
and
Stockholm
Stockholm (; ) is the Capital city, capital and List of urban areas in Sweden by population, most populous city of Sweden, as well as the List of urban areas in the Nordic countries, largest urban area in the Nordic countries. Approximately ...
on December 14, 2009, as a data connection with a USB modem. The LTE services were launched by major North American carriers as well, with the Samsung SCH-r900 being the world's first LTE Mobile phone starting on September 21, 2010, and Samsung Galaxy Indulge being the world's first LTE smartphone starting on February 10, 2011, both offered by
MetroPCS, and the
HTC ThunderBolt offered by Verizon starting on March 17 being the second LTE smartphone to be sold commercially. In Canada,
Rogers Wireless was the first to launch LTE network on July 7, 2011, offering the Sierra Wireless AirCard 313U USB mobile broadband modem, known as the "LTE Rocket stick" then followed closely by mobile devices from both HTC and Samsung. Initially, CDMA operators planned to upgrade to rival standards called
UMB and
WiMAX, but major CDMA operators (such as
Verizon
Verizon Communications Inc. ( ), is an American telecommunications company headquartered in New York City. It is the world's second-largest telecommunications company by revenue and its mobile network is the largest wireless carrier in the ...
,
Sprint and
MetroPCS in the United States,
Bell
A bell /ˈbɛl/ () is a directly struck idiophone percussion instrument. Most bells have the shape of a hollow cup that when struck vibrates in a single strong strike tone, with its sides forming an efficient resonator. The strike may be m ...
and
Telus in Canada,
au by KDDI in Japan,
SK Telecom in South Korea and
China Telecom/
China Unicom in China) have announced instead they intend to migrate to LTE. The next version of LTE is
LTE Advanced, which was standardized in March 2011.
Services commenced in 2013. Additional evolution known as
LTE Advanced Pro have been approved in year 2015.
The LTE specification provides downlink peak rates of 300 Mbit/s, uplink peak rates of 75 Mbit/s and
QoS provisions permitting a transfer
latency of less than 5
ms in the
radio access network. LTE has the ability to manage fast-moving mobiles and supports multi-cast and broadcast streams. LTE supports scalable carrier
bandwidths, from 1.4
MHz
The hertz (symbol: Hz) is the unit of frequency in the International System of Units (SI), often described as being equivalent to one event (or cycle) per second. The hertz is an SI derived unit whose formal expression in terms of SI base u ...
to 20 MHz and supports both
frequency division duplexing (FDD) and
time-division duplexing (TDD). The IP-based network architecture, called the
Evolved Packet Core (EPC) designed to replace the
GPRS Core Network, supports seamless
handovers for both voice and data to cell towers with older network technology such as
GSM
The Global System for Mobile Communications (GSM) is a family of standards to describe the protocols for second-generation (2G) digital cellular networks, as used by mobile devices such as mobile phones and Mobile broadband modem, mobile broadba ...
,
UMTS
The Universal Mobile Telecommunications System (UMTS) is a 3G mobile cellular system for networks based on the GSM standard. UMTS uses Wideband Code Division Multiple Access, wideband code-division multiple access (W-CDMA) radio access technolog ...
and
CDMA2000
CDMA2000 (also known as C2K or IMT Multi‑Carrier (IMT‑MC)) is a family of 3G mobile technology standards for sending voice, data, and signaling data between mobile phones and cell sites. It is developed by 3GPP2 as a backwards-compatib ...
.
The simpler architecture results in lower operating costs (for example, each
E-UTRA cell will support up to four times the data and voice capacity supported by HSPA
).
Because
LTE frequencies and bands differ from country to country, only multi-band phones can use LTE in all countries where it is supported.
History
3GPP standard development timeline

* In 2004,
NTT Docomo of
Japan
Japan is an island country in East Asia. Located in the Pacific Ocean off the northeast coast of the Asia, Asian mainland, it is bordered on the west by the Sea of Japan and extends from the Sea of Okhotsk in the north to the East China Sea ...
proposes LTE as the international standard.
* In September 2006, Siemens Networks (today
Nokia Networks) showed in collaboration with Nomor Research the first live emulation of an LTE network to the media and investors. As live applications, two users streaming an
HDTV
High-definition television (HDTV) describes a television or video system which provides a substantially higher image resolution than the previous generation of technologies. The term has been used since at least 1933; in more recent times, it ref ...
video in the downlink and playing an interactive game in the uplink have been demonstrated.
* In February 2007,
Ericsson
(), commonly known as Ericsson (), is a Swedish multinational networking and telecommunications company headquartered in Stockholm, Sweden. Ericsson has been a major contributor to the development of the telecommunications industry and is one ...
demonstrated for the first time in the world, LTE with bit rates up to 144 Mbit/s
* In September 2007,
NTT Docomo demonstrated LTE data rates of 200 Mbit/s with power level below 100 mW during the test.
* In November 2007,
Infineon
Infineon Semiconductor solutions is the largest microcontroller manufacturer in the world, as well as Germany's largest semiconductor manufacturer. It is also the leading automotive semiconductor manufacturer globally. Infineon had roughly 58,0 ...
presented the world's first RF transceiver named SMARTi LTE supporting LTE functionality in a single-chip RF silicon processed in CMOS
* In early 2008, LTE test equipment began shipping from several vendors and, at the
Mobile World Congress
MWC Barcelona (formerly but still commonly referred to as Mobile World Congress) is an annual trade show dedicated to the mobile communications industry.
The event is held in L'Hospitalet de Llobregat, Spain, at the Fira de Barcelona Gran ...
2008 in
Barcelona
Barcelona ( ; ; ) is a city on the northeastern coast of Spain. It is the capital and largest city of the autonomous community of Catalonia, as well as the second-most populous municipality of Spain. With a population of 1.6 million within c ...
,
Ericsson
(), commonly known as Ericsson (), is a Swedish multinational networking and telecommunications company headquartered in Stockholm, Sweden. Ericsson has been a major contributor to the development of the telecommunications industry and is one ...
demonstrated the world's first end-to-end mobile call enabled by LTE on a small handheld device.
Motorola
Motorola, Inc. () was an American multinational telecommunications company based in Schaumburg, Illinois. It was founded by brothers Paul and Joseph Galvin in 1928 and had been named Motorola since 1947. Many of Motorola's products had been ...
demonstrated an LTE RAN standard compliant
eNodeB and LTE
chipset
In a computer system, a chipset is a set of electronic components on one or more integrated circuits that manages the data flow between the processor, memory and peripherals. The chipset is usually found on the motherboard of computers. Chips ...
at the same event.
* RAN stands for Radio Access Network.
* At the February 2008
Mobile World Congress
MWC Barcelona (formerly but still commonly referred to as Mobile World Congress) is an annual trade show dedicated to the mobile communications industry.
The event is held in L'Hospitalet de Llobregat, Spain, at the Fira de Barcelona Gran ...
:
**
Motorola
Motorola, Inc. () was an American multinational telecommunications company based in Schaumburg, Illinois. It was founded by brothers Paul and Joseph Galvin in 1928 and had been named Motorola since 1947. Many of Motorola's products had been ...
demonstrated how LTE can accelerate the delivery of personal media experience with HD video demo streaming, HD video blogging, Online gaming, and VoIP over LTE running a RAN standard-compliant LTE network & LTE chipset.
**
Ericsson
(), commonly known as Ericsson (), is a Swedish multinational networking and telecommunications company headquartered in Stockholm, Sweden. Ericsson has been a major contributor to the development of the telecommunications industry and is one ...
EMP (later
ST-Ericsson) demonstrated the world's first end-to-end LTE call on handheld
Ericsson demonstrated LTE FDD and TDD mode on the same base station platform.
**
Freescale Semiconductor demonstrated streaming HD video with peak data rates of 96 Mbit/s downlink and 86 Mbit/s uplink.
**
NXP Semiconductors
NXP Semiconductors N.V. is a Dutch semiconductor manufacturing and design company with headquarters in Eindhoven, Netherlands. It is the third largest European semiconductor company by market capitalization as of 2024. The company employs approx ...
(later part of
ST-Ericsson) demonstrated a multi-mode LTE modem as the basis for a
software-defined radio system for use in cellphones.
**
picoChip and Mimoon demonstrated a base station reference design. This runs on a common hardware platform (multi-mode /
software-defined radio) with their WiMAX architecture.
* In April 2008, Motorola demonstrated the first EV-DO to LTE hand-off handing over a streaming video from LTE to a commercial EV-DO network and back to LTE.
* In April 2008,
LG Electronics
LG Electronics Inc. () is a South Korean Multinational corporation, multinational major appliance and consumer electronics corporation headquartered in Yeouido-dong, Seoul, South Korea. LG Electronics is a part of LG, LG Corporation, the fourth ...
and
Nortel demonstrated LTE data rates of 50 Mbit/s while travelling at 110 km/h (68 mph).
* In November 2008,
Motorola
Motorola, Inc. () was an American multinational telecommunications company based in Schaumburg, Illinois. It was founded by brothers Paul and Joseph Galvin in 1928 and had been named Motorola since 1947. Many of Motorola's products had been ...
demonstrated industry first over-the-air LTE session in 700 MHz spectrum.
* Researchers at
Nokia Siemens Networks and
Heinrich Hertz Institut have demonstrated LTE with 100 Mbit/s Uplink transfer speeds.
* At the February 2009
Mobile World Congress
MWC Barcelona (formerly but still commonly referred to as Mobile World Congress) is an annual trade show dedicated to the mobile communications industry.
The event is held in L'Hospitalet de Llobregat, Spain, at the Fira de Barcelona Gran ...
:
**
Infineon
Infineon Semiconductor solutions is the largest microcontroller manufacturer in the world, as well as Germany's largest semiconductor manufacturer. It is also the leading automotive semiconductor manufacturer globally. Infineon had roughly 58,0 ...
demonstrated a single-chip 65 nm
CMOS RF transceiver providing 2G/3G/LTE functionality
** Launch of ng Connect program, a multi-industry consortium founded by
Alcatel-Lucent
Alcatel-Lucent S.A. () was a multinational telecommunications equipment company, headquartered in Boulogne-Billancourt, Paris, France. The company focused on Fixed line telephone, fixed, Mobile phone, mobile and telecommunications convergence, ...
to identify and develop wireless broadband applications.
**
Motorola
Motorola, Inc. () was an American multinational telecommunications company based in Schaumburg, Illinois. It was founded by brothers Paul and Joseph Galvin in 1928 and had been named Motorola since 1947. Many of Motorola's products had been ...
provided LTE drive tour on the streets of Barcelona to demonstrate LTE system performance in a real-life metropolitan RF environment
* In July 2009, Nujira demonstrated efficiencies of more than 60% for an 880 MHz LTE Power Amplifier
* In August 2009,
Nortel and
LG Electronics
LG Electronics Inc. () is a South Korean Multinational corporation, multinational major appliance and consumer electronics corporation headquartered in Yeouido-dong, Seoul, South Korea. LG Electronics is a part of LG, LG Corporation, the fourth ...
demonstrated the first successful handoff between CDMA and LTE networks in a standards-compliant manner
* In August 2009,
Alcatel-Lucent
Alcatel-Lucent S.A. () was a multinational telecommunications equipment company, headquartered in Boulogne-Billancourt, Paris, France. The company focused on Fixed line telephone, fixed, Mobile phone, mobile and telecommunications convergence, ...
receives FCC certification for LTE base stations for the 700 MHz spectrum band.
* In September 2009,
Nokia Siemens Networks demonstrated the world's first LTE call on standards-compliant commercial software.
* In October 2009,
Ericsson
(), commonly known as Ericsson (), is a Swedish multinational networking and telecommunications company headquartered in Stockholm, Sweden. Ericsson has been a major contributor to the development of the telecommunications industry and is one ...
and
Samsung
Samsung Group (; stylised as SΛMSUNG) is a South Korean Multinational corporation, multinational manufacturing Conglomerate (company), conglomerate headquartered in the Samsung Town office complex in Seoul. The group consists of numerous a ...
demonstrated interoperability between the first ever commercial LTE device and the live network in Stockholm, Sweden.
* In October 2009,
Alcatel-Lucent
Alcatel-Lucent S.A. () was a multinational telecommunications equipment company, headquartered in Boulogne-Billancourt, Paris, France. The company focused on Fixed line telephone, fixed, Mobile phone, mobile and telecommunications convergence, ...
's Bell Labs, Deutsche
Telekom Innovation Laboratories, the Fraunhofer Heinrich-Hertz Institut, and antenna supplier Kathrein conducted live field tests of a technology called Coordinated Multipoint Transmission (CoMP) aimed at increasing the data transmission speeds of LTE and 3G networks.
* In November 2009,
Alcatel-Lucent
Alcatel-Lucent S.A. () was a multinational telecommunications equipment company, headquartered in Boulogne-Billancourt, Paris, France. The company focused on Fixed line telephone, fixed, Mobile phone, mobile and telecommunications convergence, ...
completed first live LTE call using 800 MHz spectrum band set aside as part of the European
Digital Dividend (EDD).
* In November 2009,
Nokia Siemens Networks and
LG completed first end-to-end interoperability testing of LTE.
* On December 14, 2009, the first commercial LTE deployment was in the Scandinavian capitals
Stockholm
Stockholm (; ) is the Capital city, capital and List of urban areas in Sweden by population, most populous city of Sweden, as well as the List of urban areas in the Nordic countries, largest urban area in the Nordic countries. Approximately ...
and
Oslo
Oslo ( or ; ) is the capital and most populous city of Norway. It constitutes both a county and a municipality. The municipality of Oslo had a population of in 2022, while the city's greater urban area had a population of 1,064,235 in 2022 ...
by the Swedish-Finnish network operator
TeliaSonera and its Norwegian brandname
NetCom (Norway). TeliaSonera incorrectly branded the network "4G". The modem devices on offer were manufactured by
Samsung
Samsung Group (; stylised as SΛMSUNG) is a South Korean Multinational corporation, multinational manufacturing Conglomerate (company), conglomerate headquartered in the Samsung Town office complex in Seoul. The group consists of numerous a ...
(dongle GT-B3710), and the network infrastructure with
SingleRAN technology created by
Huawei
Huawei Technologies Co., Ltd. ("Huawei" sometimes stylized as "HUAWEI"; ; zh, c=华为, p= ) is a Chinese multinational corporationtechnology company in Longgang, Shenzhen, Longgang, Shenzhen, Guangdong. Its main product lines include teleco ...
(in Oslo) and
Ericsson
(), commonly known as Ericsson (), is a Swedish multinational networking and telecommunications company headquartered in Stockholm, Sweden. Ericsson has been a major contributor to the development of the telecommunications industry and is one ...
(in Stockholm). TeliaSonera plans to roll out nationwide LTE across Sweden, Norway and Finland. TeliaSonera used spectral bandwidth of 10 MHz (out of the maximum 20 MHz), and
Single-Input and Single-Output transmission. The deployment should have provided a physical layer
net bit rates of up to 50 Mbit/s downlink and 25 Mbit/s in the uplink. Introductory tests showed a
TCP goodput of 42.8 Mbit/s downlink and 5.3 Mbit/s uplink in Stockholm.
* In December 2009,
ST-Ericsson and
Ericsson
(), commonly known as Ericsson (), is a Swedish multinational networking and telecommunications company headquartered in Stockholm, Sweden. Ericsson has been a major contributor to the development of the telecommunications industry and is one ...
first to achieve LTE and HSPA mobility with a multimode device.
* In January 2010,
Alcatel-Lucent
Alcatel-Lucent S.A. () was a multinational telecommunications equipment company, headquartered in Boulogne-Billancourt, Paris, France. The company focused on Fixed line telephone, fixed, Mobile phone, mobile and telecommunications convergence, ...
and
LG complete a live handoff of an end-to-end data call between LTE and CDMA networks.
* In February 2010,
Nokia Siemens Networks and
Movistar tested the LTE in
Mobile World Congress
MWC Barcelona (formerly but still commonly referred to as Mobile World Congress) is an annual trade show dedicated to the mobile communications industry.
The event is held in L'Hospitalet de Llobregat, Spain, at the Fira de Barcelona Gran ...
2010 in Barcelona, Spain, with both indoor and outdoor demonstrations.
* In May 2010,
Mobile TeleSystems (MTS) and
Huawei
Huawei Technologies Co., Ltd. ("Huawei" sometimes stylized as "HUAWEI"; ; zh, c=华为, p= ) is a Chinese multinational corporationtechnology company in Longgang, Shenzhen, Longgang, Shenzhen, Guangdong. Its main product lines include teleco ...
showed an indoor LTE network at "Sviaz-Expocomm 2010" in Moscow, Russia. MTS expects to start a trial LTE service in Moscow by the beginning of 2011. Earlier, MTS has received a license to build an LTE network in Uzbekistan and intends to commence a test LTE network in Ukraine in partnership with
Alcatel-Lucent
Alcatel-Lucent S.A. () was a multinational telecommunications equipment company, headquartered in Boulogne-Billancourt, Paris, France. The company focused on Fixed line telephone, fixed, Mobile phone, mobile and telecommunications convergence, ...
.
* At the Shanghai
Expo 2010 in May 2010,
Motorola
Motorola, Inc. () was an American multinational telecommunications company based in Schaumburg, Illinois. It was founded by brothers Paul and Joseph Galvin in 1928 and had been named Motorola since 1947. Many of Motorola's products had been ...
demonstrated a live LTE in conjunction with
China Mobile
China Mobile is the trade name of both China Mobile Limited and its ultimate controlling shareholder, China Mobile Communications Group Co., Ltd., a Chinese State-owned enterprises of China, state-owned telecommunicationsStrait deals ''The Econ ...
. This included video streams and a drive test system using TD-LTE.
* As of 12/10/2010,
DirecTV
DirecTV, LLC is an American Multichannel television in the United States, multichannel video programming distributor based in El Segundo, California. Originally launched on June 17, 1994, its primary service is a digital Satellite television, s ...
has teamed up with Verizon Wireless for a test of high-speed LTE wireless technology in a few homes in Pennsylvania, designed to deliver an integrated Internet and TV bundle. Verizon Wireless said it launched LTE wireless services (for data, no voice) in 38 markets where more than 110 million Americans live on Sunday, Dec. 5.
* On May 6, 2011,
Sri Lanka Telecom Mobitel demonstrated
4G LTE for the first time in South Asia, achieving a data rate of 96 Mbit/s in Sri Lanka.
Carrier adoption timeline
Most carriers supporting GSM or HSUPA networks can be expected to upgrade their networks to LTE at some stage. A complete list of commercial contracts can be found at:
* August 2009: selected six countries to field-test LTE in the succeeding months: Spain, the United Kingdom, Germany and the Czech Republic in Europe, and Brazil and Argentina in Latin America.
* On November 24, 2009:
Telecom Italia announced the first outdoor pre-commercial experimentation in the world, deployed in
Torino
Turin ( , ; ; , then ) is a city and an important business and cultural centre in northern Italy. It is the capital city of Piedmont and of the Metropolitan City of Turin, and was the first Italian capital from 1861 to 1865. The city is main ...
and totally integrated into the 2G/3G network currently in service.
* On December 14, 2009, the world's first publicly available LTE service was opened by
TeliaSonera in the two Scandinavian capitals
Stockholm
Stockholm (; ) is the Capital city, capital and List of urban areas in Sweden by population, most populous city of Sweden, as well as the List of urban areas in the Nordic countries, largest urban area in the Nordic countries. Approximately ...
and
Oslo
Oslo ( or ; ) is the capital and most populous city of Norway. It constitutes both a county and a municipality. The municipality of Oslo had a population of in 2022, while the city's greater urban area had a population of 1,064,235 in 2022 ...
.
* On May 28, 2010, Russian operator Scartel announced the launch of an LTE network in
Kazan
Kazan; , IPA: Help:IPA/Tatar, ɑzanis the largest city and capital city, capital of Tatarstan, Russia. The city lies at the confluence of the Volga and the Kazanka (river), Kazanka Rivers, covering an area of , with a population of over 1. ...
by the end of 2010.
* On October 6, 2010, Canadian provider
Rogers Communications Inc announced that Ottawa, Canada's national capital, would be the site of LTE trials. Rogers said it will expand on this testing and move to a comprehensive technical trial of LTE on both low- and high-band frequencies across the Ottawa area.
* On May 6, 2011, Sri Lanka Telecom Mobitel successfully demonstrated 4G LTE for the first time in South Asia, achieving a data rate of 96 Mbit/s in Sri Lanka.
* On May 7, 2011, Sri Lankan Mobile Operator
Dialog Axiata PLC switched on the first pilot 4G LTE Network in South Asia with vendor partner
Huawei
Huawei Technologies Co., Ltd. ("Huawei" sometimes stylized as "HUAWEI"; ; zh, c=华为, p= ) is a Chinese multinational corporationtechnology company in Longgang, Shenzhen, Longgang, Shenzhen, Guangdong. Its main product lines include teleco ...
and demonstrated a download data speed up to 127 Mbit/s.
* On February 9, 2012,
Telus Mobility launched their LTE service initial in metropolitan areas include Vancouver, Calgary, Edmonton, Toronto and the Greater Toronto Area, Kitchener, Waterloo, Hamilton, Guelph, Belleville, Ottawa, Montreal, Québec City, Halifax and
Yellowknife
Yellowknife is the capital, largest community, and the only city in the Northwest Territories, Canada. It is on the northern shore of Great Slave Lake, about south of the Arctic Circle, on the west side of Yellowknife Bay near the outlet of t ...
.
*
Telus Mobility has announced that it will adopt LTE as its 4G wireless standard.
*
Cox Communications has its first tower for wireless LTE network build-out. Wireless services launched in late 2009.
* In March 2019, the
Global Mobile Suppliers Association reported that there were now 717 operators with commercially launched LTE networks (broadband fixed wireless access and or mobile).
The following is a list of the top 10 countries/territories by 4G LTE coverage as measured by OpenSignal.com in February/March 2019.
For the complete list of all the countries/territories, see
list of countries by 4G LTE penetration.
LTE-TDD and LTE-FDD
Long-Term Evolution Time-Division Duplex (LTE-TDD), also referred to as TDD LTE, is a
4G telecommunications technology and standard co-developed by an international coalition of companies, including
China Mobile
China Mobile is the trade name of both China Mobile Limited and its ultimate controlling shareholder, China Mobile Communications Group Co., Ltd., a Chinese State-owned enterprises of China, state-owned telecommunicationsStrait deals ''The Econ ...
,
Datang Telecom,
Huawei
Huawei Technologies Co., Ltd. ("Huawei" sometimes stylized as "HUAWEI"; ; zh, c=华为, p= ) is a Chinese multinational corporationtechnology company in Longgang, Shenzhen, Longgang, Shenzhen, Guangdong. Its main product lines include teleco ...
,
ZTE,
Nokia Solutions and Networks,
Qualcomm
Qualcomm Incorporated () is an American multinational corporation headquartered in San Diego, California, and Delaware General Corporation Law, incorporated in Delaware. It creates semiconductors, software and services related to wireless techn ...
,
Samsung
Samsung Group (; stylised as SΛMSUNG) is a South Korean Multinational corporation, multinational manufacturing Conglomerate (company), conglomerate headquartered in the Samsung Town office complex in Seoul. The group consists of numerous a ...
, and
ST-Ericsson. It is one of the two mobile data transmission technologies of the Long-Term Evolution (LTE) technology standard, the other being Long-Term Evolution Frequency-Division Duplex (LTE-FDD). While some companies refer to LTE-TDD as "TD-LTE" for familiarity with
TD-SCDMA, there is no reference to that abbreviation anywhere in the 3GPP specifications.
There are two major differences between LTE-TDD and LTE-FDD: how data is uploaded and downloaded, and what frequency spectra the networks are deployed in. While LTE-FDD uses paired frequencies to upload and download data,
LTE-TDD uses a single frequency, alternating between uploading and downloading data through time.
The ratio between uploads and downloads on a LTE-TDD network can be changed dynamically, depending on whether more data needs to be sent or received.
LTE-TDD and LTE-FDD also operate on different frequency bands,
with LTE-TDD working better at higher frequencies, and LTE-FDD working better at lower frequencies.
Frequencies used for LTE-TDD range from 1850 MHz to 3800 MHz, with several different bands being used.
The LTE-TDD spectrum is generally cheaper to access, and has less traffic.
[ Further, the bands for LTE-TDD overlap with those used for WiMAX, which can easily be upgraded to support LTE-TDD.][
Despite the differences in how the two types of LTE handle data transmission, LTE-TDD and LTE-FDD share 90 percent of their core technology, making it possible for the same chipsets and networks to use both versions of LTE.] A number of companies produce dual-mode chips or mobile devices, including Samsung
Samsung Group (; stylised as SΛMSUNG) is a South Korean Multinational corporation, multinational manufacturing Conglomerate (company), conglomerate headquartered in the Samsung Town office complex in Seoul. The group consists of numerous a ...
and Qualcomm
Qualcomm Incorporated () is an American multinational corporation headquartered in San Diego, California, and Delaware General Corporation Law, incorporated in Delaware. It creates semiconductors, software and services related to wireless techn ...
, while operators CMHK and Hi3G Access have developed dual-mode networks in Hong Kong and Sweden, respectively.
History of LTE-TDD
The creation of LTE-TDD involved a coalition of international companies that worked to develop and test the technology. China Mobile
China Mobile is the trade name of both China Mobile Limited and its ultimate controlling shareholder, China Mobile Communications Group Co., Ltd., a Chinese State-owned enterprises of China, state-owned telecommunicationsStrait deals ''The Econ ...
was an early proponent of LTE-TDD, along with other companies like Datang Telecom[ and ]Huawei
Huawei Technologies Co., Ltd. ("Huawei" sometimes stylized as "HUAWEI"; ; zh, c=华为, p= ) is a Chinese multinational corporationtechnology company in Longgang, Shenzhen, Longgang, Shenzhen, Guangdong. Its main product lines include teleco ...
, which worked to deploy LTE-TDD networks, and later developed technology allowing LTE-TDD equipment to operate in white spaces—frequency spectra between broadcast TV stations. Intel
Intel Corporation is an American multinational corporation and technology company headquartered in Santa Clara, California, and Delaware General Corporation Law, incorporated in Delaware. Intel designs, manufactures, and sells computer compo ...
also participated in the development, setting up a LTE-TDD interoperability lab with Huawei in China, as well as ST-Ericsson,[ Nokia,][ and Nokia Siemens (now Nokia Solutions and Networks),] which developed LTE-TDD base stations that increased capacity by 80 percent and coverage by 40 percent. Qualcomm
Qualcomm Incorporated () is an American multinational corporation headquartered in San Diego, California, and Delaware General Corporation Law, incorporated in Delaware. It creates semiconductors, software and services related to wireless techn ...
also participated, developing the world's first multi-mode chip, combining both LTE-TDD and LTE-FDD, along with HSPA and EV-DO.[ Accelleran, a Belgian company, has also worked to build small cells for LTE-TDD networks.]
Trials of LTE-TDD technology began as early as 2010, with Reliance Industries and Ericsson India conducting field tests of LTE-TDD in India
India, officially the Republic of India, is a country in South Asia. It is the List of countries and dependencies by area, seventh-largest country by area; the List of countries by population (United Nations), most populous country since ...
, achieving 80 megabit-per second download speeds and 20 megabit-per-second upload speeds. By 2011, China Mobile began trials of the technology in six cities.
Although initially seen as a technology utilized by only a few countries, including China and India, by 2011 international interest in LTE-TDD had expanded, especially in Asia, in part due to LTE-TDD's lower cost of deployment compared to LTE-FDD. By the middle of that year, 26 networks around the world were conducting trials of the technology.[ The Global LTve (GTI) was also started in 2011, with founding partners China Mobile, Bharti Airtel, SoftBank Mobile, ]Vodafone
Vodafone Group Public Limited Company () is a British Multinational company, multinational telecommunications company. Its registered office and global headquarters are in Newbury, Berkshire, England. It predominantly operates Service (economic ...
, Clearwire, Aero2 and E-Plus. In September 2011, Huawei announced it would partner with Polish mobile provider Aero2 to develop a combined LTE-TDD and LTE-FDD network in Poland, and by April 2012, ZTE Corporation had worked to deploy trial or commercial LTE-TDD networks for 33 operators in 19 countries.[ In late 2012, Qualcomm worked extensively to deploy a commercial LTE-TDD network in India, and partnered with Bharti Airtel and Huawei to develop the first multi-mode LTE-TDD smartphone for India.][
In ]Japan
Japan is an island country in East Asia. Located in the Pacific Ocean off the northeast coast of the Asia, Asian mainland, it is bordered on the west by the Sea of Japan and extends from the Sea of Okhotsk in the north to the East China Sea ...
, SoftBank Mobile launched LTE-TDD services in February 2012 under the name Advanced eXtended Global Platform (AXGP), and marketed as SoftBank 4G ( ja). The AXGP band was previously used for Willcom's PHS service, and after PHS was discontinued in 2010 the PHS band was re-purposed for AXGP service.
In the U.S., Clearwire planned to implement LTE-TDD, with chip-maker Qualcomm agreeing to support Clearwire's frequencies on its multi-mode LTE chipsets. With Sprint's acquisition of Clearwire in 2013, the carrier began using these frequencies for LTE service on networks built by Samsung
Samsung Group (; stylised as SΛMSUNG) is a South Korean Multinational corporation, multinational manufacturing Conglomerate (company), conglomerate headquartered in the Samsung Town office complex in Seoul. The group consists of numerous a ...
, Alcatel-Lucent
Alcatel-Lucent S.A. () was a multinational telecommunications equipment company, headquartered in Boulogne-Billancourt, Paris, France. The company focused on Fixed line telephone, fixed, Mobile phone, mobile and telecommunications convergence, ...
, and Nokia
Nokia Corporation is a Finnish multinational corporation, multinational telecommunications industry, telecommunications, technology company, information technology, and consumer electronics corporation, originally established as a pulp mill in 1 ...
.
As of March 2013, 156 commercial 4G LTE networks existed, including 142 LTE-FDD networks and 14 LTE-TDD networks.[
As of November 2013, the South Korean government planned to allow a fourth wireless carrier in 2014, which would provide LTE-TDD services,][ and in December 2013, LTE-TDD licenses were granted to China's three mobile operators, allowing commercial deployment of 4G LTE services.]
In January 2014, Nokia Solutions and Networks indicated that it had completed a series of tests of voice over LTE (
VoLTE) calls on China Mobile's TD-LTE network. The next month, Nokia Solutions and Networks and Sprint announced that they had demonstrated throughput speeds of 2.6 gigabits per second using a LTE-TDD network, surpassing the previous record of 1.6 gigabits per second.
Features
Much of the LTE standard addresses the upgrading of 3G UMTS to what will eventually be 4G mobile communications technology. A large amount of the work is aimed at simplifying the architecture of the system, as it transitions from the existing UMTS circuit + packet switching
In telecommunications, packet switching is a method of grouping Data (computing), data into short messages in fixed format, i.e. ''network packet, packets,'' that are transmitted over a digital Telecommunications network, network. Packets consi ...
combined network to an all-IP flat architecture system. E-UTRA is the air interface of LTE. Its main features are:
* Peak download rates up to 299.6 Mbit/s and upload rates up to 75.4 Mbit/s depending on the user equipment category (with 4×4 antennas using 20 MHz of spectrum). Five different terminal classes have been defined from a voice-centric class up to a high-end terminal that supports the peak data rates. All terminals will be able to process 20 MHz bandwidth.
* Low data transfer latencies (sub-5 ms latency for small IP packets in optimal conditions), lower latencies for handover and connection setup time than with previous radio access technologies.
* Improved support for mobility exemplified by support for terminals moving at up to or depending on the frequency
* Orthogonal frequency-division multiple access for the downlink, Single-carrier FDMA for the uplink to conserve power.
* Support for both FDD and TDD communication systems as well as half-duplex FDD with the same radio access technology.
* Support for all frequency bands currently used by IMT systems by ITU-R.
* Increased spectrum flexibility: 1.4 MHz, 3 MHz, 5 MHz, 10 MHz, 15 MHz and 20 MHz wide cells are standardized. ( W-CDMA has no option for other than 5 MHz slices, leading to some problems rolling out in countries where 5 MHz is a commonly allocated width of the spectrum so would frequently already be in use with legacy standards such as 2G GSM and cdmaOne.)
* Support for cell sizes from tens of metres radius (femto
A metric prefix is a unit prefix that precedes a basic unit of measure to indicate a multiple (mathematics), multiple or submultiple of the unit. All metric prefixes used today are decimal, decadic. Each prefix has a unique symbol that is prepen ...
and picocells) up to radius macrocell
A macrocell or macrosite is a cell in a mobile phone network that provides radio coverage served by a high power cell site (tower, antenna or mast). Generally, macrocells provide coverage larger than microcell. The antennas for macrocells are m ...
s. In the lower frequency bands to be used in rural areas, is the optimal cell size, having reasonable performance, and up to 100 km cell sizes supported with acceptable performance. In the city and urban areas, higher frequency bands (such as 2.6 GHz in the EU) are used to support high-speed mobile broadband. In this case, cell sizes may be or even less.
* Support of at least 200 active data clients (connected users) in every 5 MHz cell.
* Simplified architecture: The network side of E-UTRAN is composed only of eNode Bs.
* Support for inter-operation and co-existence with legacy standards (e.g., GSM
The Global System for Mobile Communications (GSM) is a family of standards to describe the protocols for second-generation (2G) digital cellular networks, as used by mobile devices such as mobile phones and Mobile broadband modem, mobile broadba ...
/ EDGE, UMTS
The Universal Mobile Telecommunications System (UMTS) is a 3G mobile cellular system for networks based on the GSM standard. UMTS uses Wideband Code Division Multiple Access, wideband code-division multiple access (W-CDMA) radio access technolog ...
and CDMA2000
CDMA2000 (also known as C2K or IMT Multi‑Carrier (IMT‑MC)) is a family of 3G mobile technology standards for sending voice, data, and signaling data between mobile phones and cell sites. It is developed by 3GPP2 as a backwards-compatib ...
). Users can start a call or transfer of data in an area using an LTE standard, and, should coverage be unavailable, continue the operation without any action on their part using GSM/ GPRS or W-CDMA-based UMTS or even 3GPP2 networks such as cdmaOne or CDMA2000.
* Uplink and downlink Carrier aggregation.
* Packet-switched radio interface.
* Support for MBSFN ( multicast-broadcast single-frequency network). This feature can deliver services such as Mobile TV using the LTE infrastructure and is a competitor for DVB-H-based TV broadcast only LTE compatible devices receives LTE signal.
Voice calls
The LTE standard supports only packet switching
In telecommunications, packet switching is a method of grouping Data (computing), data into short messages in fixed format, i.e. ''network packet, packets,'' that are transmitted over a digital Telecommunications network, network. Packets consi ...
with its all-IP network. Voice calls in GSM, UMTS, and CDMA2000 are circuit switched, so with the adoption of LTE, carriers will have to re-engineer their voice call network. Four different approaches sprang up:
; Voice over LTE (VoLTE):
; Circuit-switched fallback (CSFB): In this approach, LTE just provides data services, and when a voice call is to be initiated or received, it will fall back to the circuit-switched domain. When using this solution, operators just need to upgrade the MSC instead of deploying the IMS, and therefore, can provide services quickly. However, the disadvantage is a longer call setup delay.
; Simultaneous voice and LTE (SVLTE): In this approach, the handset works simultaneously in the LTE and circuit-switched modes, with the LTE mode providing data services and the circuit-switched mode providing the voice service. This is a solution solely based on the handset, which does not have special requirements on the network and does not require the deployment of IMS either. The disadvantage of this solution is that the phone can become expensive with high power consumption.
; Single Radio Voice Call Continuity (SRVCC):
One additional approach that is not initiated by operators is the usage of over-the-top content (OTT) services, using applications like Skype
Skype () was a proprietary telecommunications application operated by Skype Technologies, a division of Microsoft, best known for IP-based videotelephony, videoconferencing and voice calls. It also had instant messaging, file transfer, ...
and Google Talk to provide LTE voice service.
Most major backers of LTE preferred and promoted VoLTE from the beginning. The lack of software support in initial LTE devices, as well as core network devices, however, led to a number of carriers promoting VoLGA
The Volga (, ) is the longest river in Europe and the longest endorheic basin river in the world. Situated in Russia, it flows through Central Russia to Southern Russia and into the Caspian Sea. The Volga has a length of , and a catchment ...
(Voice over LTE Generic Access) as an interim solution. The idea was to use the same principles as GAN (Generic Access Network, also known as UMA or Unlicensed Mobile Access), which defines the protocols through which a mobile handset can perform voice calls over a customer's private Internet connection, usually over wireless LAN. VoLGA however never gained much support, because VoLTE ( IMS) promises much more flexible services, albeit at the cost of having to upgrade the entire voice call infrastructure. VoLTE may require Single Radio Voice Call Continuity (SRVCC) to be able to smoothly perform a handover to a 2G or 3G network in case of poor LTE signal quality.
While the industry has standardized on VoLTE, early LTE deployments required carriers to introduce circuit-switched fallback as a stopgap measure. When placing or receiving a voice call on a non-VoLTE-enabled network or device, LTE handsets will fall back to old 2G or 3G networks for the duration of the call.
Enhanced voice quality
To ensure compatibility, 3GPP demands at least AMR-NB codec (narrow band), but the recommended speech codec for VoLTE is Adaptive Multi-Rate Wideband, also known as HD Voice. This codec is mandated in 3GPP networks that support 16 kHz sampling.
Fraunhofer IIS has proposed and demonstrated "Full-HD Voice", an implementation of the AAC-ELD (Advanced Audio CodingEnhanced Low Delay) codec for LTE handsets. Where previous cell phone voice codecs only supported frequencies up to 3.5 kHz and upcoming wideband audio services branded as ''HD Voice'' up to 7 kHz, Full-HD Voice supports the entire bandwidth range from 20 Hz to 20 kHz. For end-to-end Full-HD Voice calls to succeed, however, both the caller's and recipient's handsets, as well as networks, have to support the feature.
Frequency bands
The LTE standard covers a range of many different bands, each of which is designated by both a frequency and a band number:
* North America 600, 700, 850, 1700, 1900, 2300, 2500, 2600, 3500, 5000 MHz (bands 2, 4, 5, 7, 12, 13, 14, 17, 25, 26, 28, 29, 30, 38, 40, 41, 42, 43, 46, 48, 66, 71)
* Central America, South America and the Caribbean 600, 700, 800, 850, 900, 1700, 1800, 1900, 2100, 2300, 2500, 2600, 3500, 5000 MHz (bands 1, 2, 3, 4, 5, 7, 8, 12, 13, 14, 17, 20, 25, 26, 28, 29, 38, 40, 41, 42, 43, 46, 48, 66, 71)
* Europe 450, 700, 800, 900, 1500, 1800, 2100, 2300, 2600, 3500, 3700 MHz (bands 1, 3, 7, 8, 20, 22, 28, 31, 32, 38, 40, 42, 43)
* Asia 450, 700, 800, 850, 900, 1500, 1800, 1900, 2100, 2300, 2500, 2600, 3500 MHz (bands 1, 3, 5, 7, 8, 11, 18, 19, 20, 21, 26, 28, 31, 38, 39, 40, 41, 42)
* Africa 700, 800, 850, 900, 1800, 2100, 2300, 2500, 2600 MHz (bands 1, 3, 5, 7, 8, 20, 28, 40, 41)
* Oceania (incl. Australia and New Zealand) 700, 850, 900, 1800, 2100, 2300, 2600 MHz (bands 1, 3, 5, 7, 8, 28, 40)
As a result, phones from one country may not work in other countries. Users will need a multi-band capable phone for roaming internationally.
Patents
According to the European Telecommunications Standards Institute's (ETSI) intellectual property
Intellectual property (IP) is a category of property that includes intangible creations of the human intellect. There are many types of intellectual property, and some countries recognize more than others. The best-known types are patents, co ...
rights (IPR) database, about 50 companies have declared, as of March 2012, holding essential patents covering the LTE standard. The ETSI has made no investigation on the correctness of the declarations however, so that "any analysis of essential LTE patents should take into account more than ETSI declarations." Independent studies have found that about 3.3 to 5 percent of all revenues from handset manufacturers are spent on standard-essential patents. This is less than the combined published rates, due to reduced-rate licensing agreements, such as cross-licensing.
See also
* 4G-LTE filter
* Comparison of wireless data standards
* E-UTRAthe radio access network used in LTE
* HSPA+
HSPA may refer to:
* High Speed Packet Access, a mobile broadband technology
* Hawaiian Sugar Planters' Association
Education
* High School Proficiency Assessment
* Humphrey School of Public Affairs, an American public policy school
* Hunte ...
an enhancement of the 3GPP HSPA standard
* Flat IPflat IP architectures in mobile networks
* LTE-A
* LTE-A Pro
* LTE-U
* NarrowBand IoT
Narrowband Internet of things (NB-IoT) is a low-power wide-area network (LPWAN) radio technology standard developed by 3GPP for cellular network devices and services. The specification was frozen in 3GPP Release 13 ( LTE Advanced Pro), in June ...
(NB-IoT)
* Simulation of LTE Networks
* QoS Class Identifier (QCI) the mechanism used in LTE networks to allocate proper Quality of Service to bearer traffic
* System Architecture Evolutionthe re-architecturing of core networks in LTE
* VoLTE
* WiMAXa competitor to LTE
* 5G NR
5G NR (5G New Radio) is a radio access technology (RAT) developed by the 3rd Generation Partnership Project (3GPP) for the 5G (fifth generation) mobile network. It was designed to be the global standard for the air interface of 5G networks. It is ...
the successor to LTE
References
Further reading
* Agilent Technologies,
LTE and the Evolution to 4G Wireless: Design and Measurement Challenges
'', John Wiley & Sons, 2009
* Beaver, Paul,
What is TD-LTE?
, RF&Microwave Designline, September 2011.
* E. Dahlman, H. Ekström, A. Furuskär, Y. Jading, J. Karlsson, M. Lundevall, and S. Parkvall, "The 3G Long-Term EvolutionRadio Interface Concepts and Performance Evaluation", IEEE Vehicular Technology Conference (VTC) 2006 Spring, Melbourne, Australia, May 2006
* Erik Dahlman, Stefan Parkvall, Johan Sköld, Per Beming, ''3G EvolutionHSPA and LTE for Mobile Broadband'', 2nd edition, Academic Press, 2008,
* Erik Dahlman, Stefan Parkvall, Johan Sköld, ''4GLTE/LTE-Advanced for Mobile Broadband'', Academic Press, 2011,
* Sajal K. Das, John Wiley & Sons (April 2010):
Mobile Handset Design
', .
* Sajal K. Das, John Wiley & Sons (April 2016):
Mobile Terminal Receiver Design: LTE and LTE-Advanced
', .
* H. Ekström, A. Furuskär, J. Karlsson, M. Meyer, S. Parkvall, J. Torsner, and M. Wahlqvist, "Technical Solutions for the 3G Long-Term Evolution", ''IEEE Commun. Mag.'', vol. 44, no. 3, March 2006, pp. 38–45
* Mustafa Ergen, ''Mobile Broadband: Including WiMAX and LTE'', Springer, NY, 2009
* K. Fazel and S. Kaiser, ''Multi-Carrier and Spread Spectrum Systems: From OFDM and MC-CDMA to LTE and WiMAX'', 2nd Edition, John Wiley & Sons, 2008,
* Dan Forsberg, Günther Horn, Wolf-Dietrich Moeller, Valtteri Niemi, ''LTE Security'', Second Edition, John Wiley & Sons Ltd, Chichester 2013,
* Borko Furht, Syed A. Ahson, ''Long Term Evolution: 3GPP LTE Radio and Cellular Technology'', CRC Press, 2009,
* Chris Johnson,
LTE in BULLETS
', CreateSpace, 2010,
* F. Khan, ''LTE for 4G Mobile BroadbandAir Interface Technologies and Performance'', Cambridge University Press, 2009
* Guowang Miao, Jens Zander, Ki Won Sung, and Ben Slimane, ''Fundamentals of Mobile Data Networks'', Cambridge University Press, 2016,
* Stefania Sesia, Issam Toufik, and Matthew Baker, ''LTEThe UMTS Long Term Evolution: From Theory to Practice'', Second Edition including Release 10 for LTE-Advanced, John Wiley & Sons, 2011,
* Gautam Siwach, Amir Esmailpour, "LTE Security Potential Vulnerability and Algorithm Enhancements", IEEE Canadian Conference on Electrical and Computer Engineering (IEEE CCECE), Toronto, Canada, May 2014
* SeungJune Yi, SungDuck Chun, YoungDae lee, SungJun Park, SungHoon Jung, ''Radio Protocols for LTE and LTE-Advanced'', Wiley, 2012,
* Y. Zhou, Z. Lei and S. H. Wong
Evaluation of Mobility Performance in 3GPP Heterogeneous Networks
2014 IEEE 79th Vehicular Technology Conference (VTC Spring), Seoul, 2014, pp. 1–5.
External links
LTE homepage
from the 3GPP website
LTE Frequently Asked Questions
LTE-3GPP.info: online LTE messages decoder fully supporting Rel.14
{{Authority control
Wireless networking standards
Japanese inventions
Mobile telecommunications
Mobile telecommunications standards
Telecommunications