4G History and Current Status

                       History of 4G and pre-4G technologies

       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.

• In 2002, the strategic vision for 4G—which ITU designated as IMT-Advanced—was laid out.
• In 2005, OFDMA transmission technology is chosen as candidate for the HSOPA downlink, later renamed 3GPP Long Term Evolution (LTE) air interface E-UTRA.
• In November 2005, KT demonstrated mobile WiMAX service in Busan, South Korea.
• In April 2006, KT started the world's first commercial mobile WiMAX service in Seoul, South Korea.
• In mid-2006, Sprint announced that it would invest about US$5 billion in a WiMAX technology buildout over the next few years ($5.69 billion in real terms). Since that time Sprint has faced many setbacks that have resulted in steep quarterly losses. On 7 May 2008, Sprint, Imagine, Google, Intel, Comcast, Bright House, and Time Warner announced a pooling of an average of 120 MHz of spectrum; Sprint merged its Xohm WiMAX division with Clearwire to form a company which will take the name "Clear".
• In February 2007, the Japanese company NTT DoCoMo tested a 4G communication system prototype with 4×4 MIMO 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 12×12 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 (FCC) spectrum auction 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.
• In January 2008, EU commissioner Viviane Reding 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 November 2008, ITU-R 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 announced the first WiMAX-enabled mobile phone, the Max 4G
• In 15 December 2008, San Miguel Corporation, the largest food and beverage conglomeratein southeast Asia, has signed a memorandum of understanding with Qatar Telecom QSC (Qtel) 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 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 and Oslo by the Swedish-Finnish network operator TeliaSonera and its Norwegian brandname NetCom (Norway). TeliaSonera branded the network "4G". The modem devices on offer were manufactured by Samsung (dongle GT-B3710), and the network infrastructure created by Huawei (in Oslo) and Ericsson (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 throughput of 42.8 Mbit/s downlink and 5.3 Mbit/s uplink in Stockholm.
• On 25 February 2010, Estonia's EMT opened LTE "4G" network working in test regime.
• On 4 June 2010, Sprint released the first WiMAX smartphone in the US, the HTC Evo 4G.
• In July 2010, Uzbekistan's MTS deployed LTE in Tashkent.
• On 25 August 2010, Latvia's LMT opened LTE "4G" network working in test regime 50% of territory.
• On November 4, 2010, the Samsung Galaxy Craft offered by MetroPCS is the first commercially available LTE smartphone
• On 6 December 2010, at the ITU World Radiocommunication Seminar 2010, the ITU stated that LTE, WiMax and similar "evolved 3G technologies" could be considered "4G".
• On 12 December 2010, VivaCell-MTS launches in Armenia a 4G/LTE commercial test network with a live demo conducted in Yerevan.
• On 28 April 2011, Lithuania's Omnitel opened a LTE "4G" network working in the 5 largest cities.
• In September 2011, all three Saudi telecom companies STC, Mobily and Zain announced that they will offer 4G LTE for USB modem dongles, with further development for phones by 2013.
• In 2011, Argentina's Claro launched a 4G HSPA+ network in the country.
• In 2011, Thailand's Truemove-H launched a 4G HSPA+ network with nation-wide availability.
• On March 17, 2011, the HTC Thunderbolt offered by Verizon in the U.S. was the second LTE smartphone to be sold commercially.
• On 31 January 2012, Thailand's AIS and its subsidiaries DPC under cooperation with CAT Telecom for 1800 MHz frequency band and TOT for 2300 MHz frequency band launched the first field trial LTE in Thailand with authorization from NBTC.
• In February 2012, Ericsson demonstrated mobile-TV over LTE, utilizing the new eMBMS service (enhanced Multimedia Broadcast Multicast Service).
• On 10 April 2012, Bharti Airtel launched 4G LTE in Kolkata, first in India.
• On 20 May 2012, Azerbaijan's biggest mobile operator Azercell launched 4G LTE.
• On 10 October 2012, Vodacom (Vodafone South Africa) became the first operator in South Africa to launch a commercial LTE service.
• In December 2012, Telcel launches in Mexico the 4G LTE network in 9 major cities
• In Kazakhstan, 4G LTE was launched on December 26, 2012 in the entire territory in the frequency bands 1865-1885/1760 - 1780 MHz for the urban population and in 794-799/835-840 MHz for those sparsely populated

 4G in INDIA:

Bharti Airtel launched India's first 4G service, using TD-LTE technology, in Kolkata on April 10, 2012.Fourteen months prior to the official launch in Kolkata, a group consisting of China Mobile, Bharti Airtel and SoftBank Mobile came together, called Global TD-LTE Initiative (GTI) in Barcelona, Spain and they signed the commitment towards TD-LTE standards for the Asian region. It must be noted that Airtel's 4G network does not support mainstream 4G phones such as Apple iPhone 5, Samsung Galaxy S III, Nokia Lumia 920 and others.

• Airtel 4G services are available in Kolkata, Bangalore, Pune and Chandigarh region (The Tricity or Chandigarh region consists of a major city Chandigarh, Mohali and Panchkula.
• RIL is launching 4G services through its subsidiary, Jio Infocomm. RIL 4G services are currently available only in Jamnagar, where it is testing the new TD-LTE technology. RIL 4G rollout is planned to start in Delhi, Mumbai and Kolkata and expand to cover 700 cities, including 100 high-priority markets.

India uses the TD LTE frequency #40 (2.3 GHz), Apple iPhone 5s supports the TD LTE 40 band but its yet to be launched in India.

 Advancement:

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, 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, IEEE 802.21). These access technologies can be Wi-Fi, UMTS, EDGE, or any other future access technology. Included in this concept is also smart-radio (also known as cognitive radio) technology to efficiently manage spectrum use and transmission power as well as the use of mesh routing protocols to create a pervasive network.