Technology EDGE (an Enhanced Data rate for Global Evolution is the improved transfer rates for GSM-standard evolution) as it is easy to guess from its name plays at once two roles: first, provides higher capacity for transmission and reception of the data, and secondly, is for one more step on path from GSM to UMTS. The First step is implantation GPRS, is already made. Not far off and the second step is the implantation where EDGE has already started in the world.

For the first time EDGE has been presented ETSI (the European institute of standardization of telecommunication) in the beginning of 1997 as evolution of existing standard GSM. EDGE uses the same pass-band and structure of time slots, as GSM. Thus the operator can continue to use already available ranges of frequencies on 200 kgc, structure of channels and frequency schedules, thus offering the abonents a number of services of the third generation.

Moreover, used in EDGE the package format completely is identical to a similar package in TDMA or GSM. It includes test sequence from 26 characters at the package centre, two tail sequences from three characters from each end of the package, two sequences with the data on 58 characters and check sequence from 8.25 characters.

Technology EDGE can take root in two different ways: as GPRS extension, in this case it is necessary to name EGPRS (enhanced GPRS) or as CSD (ECSD extension. Considering that GPRS it is extended much more widely, than HSCSD, we will stop on consideration EGPRS.

EDGE is not the new standard of cellular communication.

However, EDGE means additional physical level which can be used for increase in capacity of tools GPRS or HSCSD. Thus, tools are given in the same way, as before. Theoretically, tools GPRS is capable to provide conducting to 160 Kbit/with (at physical level, in practice supporting GPRS Class 10 or 4+1/3+2 devices provide only till 38-42 Kbit/with and if congestion of a network of cellular communication allows), and EGPRS — to 384-473,6 Kbit/with. For this purpose usage of the new modulation circuit, new methods of coding of channels and an error correction are necessary.

EDGE, as a matter of fact, is “deckhouse” (more truly, setup if to consider that physical level is below the others) to GPRS and cannot separately exist from GPRS. EDGE as already it has been told above, means usage of other modulation and code circuits, saving compatibility with voice communication CSD-service.

Thus, from the point of view of the client terminal, implantation of EDGE should not vary anything. However, the infrastructure of the base server will undergo some changes, though and not such the serious. Besides increase in capacity for data transfer, implantation of EDGE increases capacity of a network of cellular communication: it is possible to “pack” into the same time SLOT now bigger quantity of users, accordingly, it is possible to hope not to receive the message “a network it is occupied” in the inopportune moments.

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For those who regularly uses a mobile communication or whom novelties in this area interest, any more you will not surprise with a short abbreviation “3G” which carries in itself the huge maintenance of the third generation of a mobile communication. To understand, how there was a third generation, it is necessary to know its short history.

The mobile communication first generation (1G) has arisen in the seventies. All first systems of cellular communication were analogue. They intended only for a voice transfer. Standards AMPS, NMT, TACS – the most known representatives of 1G. These standards were continuously upgraded, enriched by new possibilities and, thus, are to this day.

The second generation (2G) provided the abonent transmission and reception of the voice, the given and fax messages. Now, systems of the second generation still develop with permanently increasing transfer rates, by means of technologies of type HSCSD and GPRS. Systems of the second generation include GSM, DAMPS (IS-136), cdma One (IS-95) and PDC. DAMPS/PDC have structurally been imposed on existing systems of a first generation and serviced in a parallel way with them. GSM/IS-95, on the other hand, is grounded on completely new concept, and have gained the greatest distribution all over the world.

Transition to technologies of the third generation (Third Generation, 3G) allows operators to fall forward the data in networks and to offer abonents new services – high-speed access to the Internet, a transportable television etc.

Though there are many various interpretations of that represents 3G, the unique definition accepted universally, the definition published by the International Institute of Telecommunication (ITU) is. ITU, working with the industrial organizations worldwide, defines and confirms technical requirements and standards, and also rules of usage of a spectrum for systems 3G within the limits of program IMT-2000 (International Mobile Telecommunications-2000).

IMT-2000 is the guidelines developed by the International Institute of Telecommunication (ITU), usages of a frequency spectrum concerning questions and technical features for all set of standards of 3rd generation. Guidelines describe paths of evolution of 2nd generation existing in the world in standards of 3rd generation. ITU says, that IMT-2000 (3G)network, besides other properties, provided the improved capacity of system and efficiency of usage of a spectrum for systems 2G and supported tools of data transfer with speeds – a minimum 144 Kbit/with, at usage in a transportable mode (not in premises), and a maximum 2 Mbita/with, in not transportable conditions (in premises).

Being grounded on these requirements, in 1999 ITU has approved five radio interfaces for standards IMT-2000, as a part of guidelines ITU-R M.1457. CDMA2000 is one of five mentioned standards. It also is known under the name IMT-CDMA Multi Carrier in classification ITU.

Being grounded on these requirements, in 1999 ITU has approved five radio interfaces for standards IMT-2000, as a part of guidelines ITU-R M.1457. CDMA2000 is one of five mentioned standards.

CDMA2000 3G presents almost realizable solution for any existing on the market PCS operator. CDMA2000 has been developed in such a manner that any carrier, without dependence from the interface, frequency or backbone network standards, can benefit by its spectral efficiency.

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What is GPRS?

GPRS (General Packet Radio Service — a package radio communication of the common using) – a deckhouse over technology of mobile communication GSM, carrying out a packet transmission of the data, allowing to work in an Internet network, using a usual mobile phone. Standardization of this technology has started in 1993 in European Telecommunication Standards Institute (ETSI – the European institute of standardization of telecommunication). By means of GPRS, users can work with the e-mail, with usual Web-servers (instead of with special WAP-versions) etc.

Before development of technology GPRS the abonent paid all time of connection irrespective of, whether it used the installed data channel. The main advantage of GPRS-networks consists that the user pays only size of the transferred/received information, instead of finding time in a network. Differently, network resources are involved only during direct data transfer from phone. During pauses (for example, review of received e-mail) network resources are given in the instruction of other abonents.

Standard GSM with technology GPRS is intermediate between the second and third generations of link, therefore quite often is named as the generation second and a half (2,5G). It is named so also because GPRS marks itself half of path of GSM/GPRS-networks to compatibility with UMTS.

In GPRS the greatest possible transfer rate makes 171,2 Kbit/with is almost in 12 times faster data transfer operations in usual networks GSM (9,6 Kbit/c). However at present speed is not so high – usually 30-40 Kbit/with. Now practically all cellular operators offer the abonents GPRS service.

Structure:

Data-transport service GPRS is raised over existing network GSM. At structural level system GPRS can be divided on two parts: a subsystem of base servers (BSS) and backbone GPRS (GPRS Core Network).

In BSS all base servers and controllers which support a packet transmission of the data enter. For this purpose BSC (Base Station Controller) it is supplemented with the block of handle of packages — PCU (Packet Controller Unit), and BTS (Base Transceiver Station) — coder CCU (Channel Codec Unit).

Backbone basic element is the service site of support GPRS — SGSN (Serving GPRS Support Node). He is engaged in processing of the package information and conversion of data frames GSM to the formats used by TCP/IP protocols.

Gateway servers with external networks (the Internet, intranet, X.25) name GGSN (Gateway GPRS Support Node). Information interchange between SGSN and GGSN occurs on the basis of IP-reports.

Also into structure GPRS Core enter DNS (Domain Name System) and Charging Gateway (the gateway server for link with tariffing system).

Operation principle

At usage GPRS the information is gathered in packages and transferred through vocal channels not used at present, such technology assumes more an effective utilization of resources of network GSM. Thus the priority of transmission — the vocal traffic or data transfer — is selected by a communication statement. Possibility of usage several channels provides at once enough high speeds of data transfer, the theoretical maximum at all occupied TDMA time slots makes 171,2 Kbit/c. There are the various classes GPRS differing with a transfer rate and possibility of combination of data transfer with simultaneous vocal call.

Modern digital technologies have absorbed the world and our minds. Can you just imagine our life without all those computers, phones and automated machines? We have become so obsessed by our cell phones that if we leave our house without it we get stress. Cell phone has become our inseparable part which requires its own accessories. Those who are looking for Motorola Droid X Accessories, are welcomed to this cell phone accessories site. This site can offer a lot of accessories, including HTC Evo 4G Accessories.

Don’t get upsent if you haven’t found the wanted one, keep in mind that our world is the world of online technologies. Use Google and other search engines, go to forums and social networks, subscribe to RSS on the blogs – all this will assist you to find what you require on the best terms available on the market.

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