GSM - Wikipedia. The GSM logo is used to identify compatible devices and equipment. The dots symbolize three clients in the home network and one roaming client.[1]GSM (Global System for Mobile Communications, originally Groupe Spécial Mobile) is a standard developed by the European Telecommunications Standards Institute (ETSI) to describe the protocols for second- generation digital cellular networks used by mobile devices such as tablets, first deployed in Finland in December 1. As of 2. 01. 4[update], it has become the global standard for mobile communications – with over 9. G networks developed as a replacement for first generation (1. G) analog cellular networks, and the GSM standard originally described as a digital, circuit- switched network optimized for full duplex voice telephony. This expanded over time to include data communications, first by circuit- switched transport, then by packet data transport via GPRS (General Packet Radio Services) and EDGE (Enhanced Data rates for GSM Evolution, or EGPRS). The purpose of this webpage is to provide information (a majority are secret or are hard to find) on the iPhone, iPad, and iPod touch. It will mainly concentrate on. Subsequently, the 3. GPP developed third- generation (3. ![]() Steps to activate Reliance Jio sim. If you don’t know how to get free Jio sim, please refer to this article first. All you will need is Aadhar card & barcode.G) UMTS standards, followed by fourth- generation (4. G) LTE Advanced standards, which do not form part of the ETSI GSM standard."GSM" is a trademark owned by the GSM Association. It may also refer to the (initially) most common voice codec used, Full Rate. History[edit]In 1. European standard for digital cellular voice telecommunications when the European Conference of Postal and Telecommunications Administrations (CEPT) set up the Groupe Spécial Mobile committee and later provided a permanent technical- support group based in Paris. Five years later, in 1. European countries signed a memorandum of understanding in Copenhagen to develop and deploy a common cellular telephone system across Europe, and EU rules were passed to make GSM a mandatory standard.[4] The decision to develop a continental standard eventually resulted in a unified, open, standard- based network which was larger than that in the United States.[5][6][7][8]In February 1. Europe produced the very first agreed GSM Technical Specification. Ministers from the four big EU countries cemented their political support for GSM with the Bonn Declaration on Global Information Networks in May and the GSM Mo. U was tabled for signature in September. The Mo. U drew in mobile operators from across Europe to pledge to invest in new GSM networks to an ambitious common date. In this short 3. 8- week period, the whole of Europe (countries and industries) had been brought behind GSM in a rare unity and speed guided by four public officials: Armin Silberhorn (Germany), Stephen Temple (UK), Philippe Dupuis (France), and Renzo Failli (Italy).[9] In 1. Groupe Spécial Mobile committee was transferred from CEPT to the European Telecommunications Standards Institute (ETSI).[6][7][7][8]In parallel, France and Germany signed a joint development agreement in 1.
Italy and the UK in 1. In 1. 98. 6, the European Commission proposed reserving the 9. MHz spectrum band for GSM. The former Finnish prime minister Harri Holkeri made the world's first GSM call on July 1, 1. Kaarina Suonio (mayor of the city of Tampere) using a network built by Telenokia and Siemens and operated by Radiolinja.[1. In the following year, 1. SMS or "text message") message, and Vodafone UK and Telecom Finland signed the first international roaming agreement. Work began in 1. 99. GSM standard to the 1. MHz frequency band and the first 1. MHz network became operational in the UK by 1. DCS 1. 80. 0. Also that year, Telecom Australia became the first network operator to deploy a GSM network outside Europe and the first practical hand- held GSM mobile phone became available. In 1. 99. 5, fax, data and SMS messaging services were launched commercially, the first 1. MHz GSM network became operational in the United States and GSM subscribers worldwide exceeded 1. In the same year, the GSM Association formed. Pre- paid GSM SIM cards were launched in 1. GSM subscribers passed 1. In 2. 00. 0, the first commercial GPRS services were launched and the first GPRS- compatible handsets became available for sale. In 2. 00. 1, the first UMTS (W- CDMA) network was launched, a 3. G technology that is not part of GSM. Worldwide GSM subscribers exceeded 5. In 2. 00. 2, the first Multimedia Messaging Service (MMS) were introduced and the first GSM network in the 8. MHz frequency band became operational. EDGE services first became operational in a network in 2. GSM subscribers exceeded 1 billion in 2. By 2. 00. 5, GSM networks accounted for more than 7. In 2. 00. 5, the first HSDPA- capable network also became operational. The first HSUPA network launched in 2. High- Speed Packet Access (HSPA) and its uplink and downlink versions are 3. G technologies, not part of GSM.) Worldwide GSM subscribers exceeded three billion in 2. The GSM Association estimated in 2. GSM standard served 8. GSM the most ubiquitous of the many standards for cellular networks.[1. GSM is a second- generation (2. G) standard employing time- division multiple- Access (TDMA) spectrum- sharing, issued by the European Telecommunications Standards Institute (ETSI). The GSM standard does not include the 3. G Universal Mobile Telecommunications System (UMTS) code division multiple access (CDMA) technology nor the 4. G LTE orthogonal frequency- division multiple access (OFDMA) technology standards issued by the 3. GPP.[1. 2]GSM, for the first time, set a common standard for Europe for wireless networks. It was also adopted by many countries outside Europe. This allowed subscribers to use other GSM networks that have roaming agreements with each other. The common standard reduced research and development costs, since hardware and software could be sold with only minor adaptations for the local market.[1. Telstra in Australia shut down its 2. G GSM network on December 1, 2. GSM network.[1. 4] The second mobile provider to shut down its GSM network (on January 1, 2. AT& T Mobility from the United States.[1. Optus in Australia completed the shut down its 2. G GSM network on August 1, 2. Optus GSM network covering Western Australia and the Northern Territory had earlier in the year been shut down in April 2. Singapore will phase out 2. G services by April 2. Technical details[edit]. The structure of a GSM network. Network structure[edit]The network is structured into a number of discrete sections: Base station subsystem[edit]GSM is a cellular network, which means that cell phones connect to it by searching for cells in the immediate vicinity. There are five different cell sizes in a GSM network—macro, micro, pico, femto, and umbrella cells. The coverage area of each cell varies according to the implementation environment. Macro cells can be regarded as cells where the base stationantenna is installed on a mast or a building above average rooftop level. Micro cells are cells whose antenna height is under average rooftop level; they are typically used in urban areas. Picocells are small cells whose coverage diameter is a few dozen meters; they are mainly used indoors. Femtocells are cells designed for use in residential or small business environments and connect to the service provider’s network via a broadband internet connection. Umbrella cells are used to cover shadowed regions of smaller cells and fill in gaps in coverage between those cells. Cell horizontal radius varies depending on antenna height, antenna gain, and propagation conditions from a couple of hundred meters to several tens of kilometres. The longest distance the GSM specification supports in practical use is 3. There are also several implementations of the concept of an extended cell,[1. Indoor coverage is also supported by GSM and may be achieved by using an indoor picocell base station, or an indoor repeater with distributed indoor antennas fed through power splitters, to deliver the radio signals from an antenna outdoors to the separate indoor distributed antenna system. These are typically deployed when significant call capacity is needed indoors, like in shopping centers or airports. However, this is not a prerequisite, since indoor coverage is also provided by in- building penetration of the radio signals from any nearby cell. GSM carrier frequencies[edit]GSM networks operate in a number of different carrier frequency ranges (separated into GSM frequency ranges for 2. G and UMTS frequency bands for 3. G), with most 2. G GSM networks operating in the 9. MHz or 1. 80. 0 MHz bands. Where these bands were already allocated, the 8.
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