What is not a cellular standard. WCDMA or GSM standard: What is the difference between them? History of the Communications RF: Frequency

Generations of mobile telephony

Generation			2.5G.		3.5G.
Getting started	1970	1980	1985	1990	until 2000.	since 2000.
Implementation	1984	1991	1999	2002	2006-2007	2008-2010
Services	analog standard, synchronous data transmission at a speed of up to 9.6 kbps	digital Standard, Support Short Community (SMS)	large capacity, packet data transmission	even greater capacity, high speeds	an increase in the speed of third-generating networks	large capacity IP-oriented Network, support multimet, speed to hundreds Mbit / S.
Channel width	1,9 Kbit / S.	14,4 Kbit / S.	384 Kbit / S.	2 Mbit / S.	3-14 Mbps	1 Gbit / s
Standarti	AMPS, TACS, Nmt.	TDMA, CDMA, CDMA One, GSM, PDC, Damps.	GPRS, EDGE, 1XRTT	WCDMA, CDMA 2000, UMTS	HSDPA.	single Standard
Net			PSTN,	packet data network	packet data network	the Internet

AMPS / D-AMPS / N-AMPS

AMPS standard mobile communication system ( Advanced Mobile PHONE SERVICE) was first commissioned in the USA in 1979. The system operates in the range of 825-890 MHz and has 666 duplex channels with a bandwidth of each channel of 30 kHz. The power of the base station transmitter is 45 watts, a car mobile station - 12 W, a portable apparatus - 1 W. The standard uses a number of original technical solutionsaimed at ensuring high-quality communication at the minimum cost of equipment.

Based on this standard, two modifications were developed in the future: Analog N-AMPS (Narrowband Advanced Mobile Phone Service) and digital D-AMPS (Digital Advanced Mobile Phone Service). Both of these options were created, first of all, to accommodate in the highlighted frequency frequency frequencies of a larger number of conversational channels. In N-AMPS, this is achieved by using narrower channel frequency bands, and in D-APS uses the temporary separation of the channels. In the Cellular communication system, the AMPS is used base stations with antennas that have a width of 120 ° diagram, which are installed in cell corners. Basic stations are connected to switching centers using wired lines for which speech signals and service information are transmitted. The length of the control message transmitted to the subscriber is 463 bits.

D-AMPS standard has disadvantages: a small coverage area of \u200b\u200bone base station, an increased power of the base station transmitter, poor support among equipment manufacturers, because The standard is already out of use. Of the advantages worth noting the relative cheapness of the network organization, quite high quality and confidentiality of conversations, in the zone of confident reception - automatic switching to analog mode for better voice transmission.

TACS (Total Access Control System) - almost full AMPS analog - got the most distribution. In 1985, the first TACS network was deployed in England. After that, during a couple of years, TACS network covered the territory of Spain, Austria, Ireland and Italy. In 1987, the first modification of the standard - ETACS (Extended TACS) appeared, which possessed a little greater capacity (640 against 600 channels). However, despite improvements, networks based on ETACS outside of England practically did not spread. The second modification of the standard - JTACS or NTACS (Japan or Narrowband Tacs) was intended solely for Japan. The differences between NTACS from TACS, one can say, were standard: due to the larger range of the selected frequencies and the smaller communication channel, the system has increased the total number of channels - in fact NTACS was an analogue of NAMPS. Networks based on TACS were very survivors - only in the late 90s Japan turned the JTACS network; In the homeland of the standard and in other European countries, this event occurred a little earlier.

NMT (Nordic Mobile Telephone) - Cellular Mobile Radio System common use first generation. This is one of the oldest standards of cellular communication in the world, it was developed in 1978 and commissioned in 1981. The standard was developed for locality with a large territory and a small population density, so it should not be better approached for Russia.

NMT standard is analog, it follows it chief flaw - Bad noise immunity, in large cities there are a significant level of interference on the frequency range of about 450 MHz. However, it is worth removing from the city - the quality of communication is greatly improved and sometimes exceeds the quality of wired telephone networks. The main advantage is a large radius of the base station. Quite a decent connection is observed in 70 km from the base station. By comparison, the GSM-900 phone, for example, cannot work at a distance of more than 35 km from the base station.

The frequency range in which NMT: 453-457,5 MHz works - for communication from the phone to the base station, 463-467.5 MHz - for communication from the base station to the phone. The step of the channels of the channels is 25 kHz (12.5 kHz when using interliving), the maximum capacity of one base station is 180 (359 - during interliming) subscribers. Power of transmitters of subscriber devices 0.1-6.5 W.

NMT is a federal standard, so you can easily go on a trip to the country with the NMT phone. As for international roaming - here the situation is worse, all over the world NMT network is slowly collapsed in favor of new, more modern standards.

TDMA (Time Division Multiple Access) - multiple access with temporary separation. The TDMA standard is actively used by modern digital mobile communication systems. In contrast to the partial separation systems, all TDMA subscribers work in the same frequency range, but each has temporary access restrictions. Each subscriber is distinguished by the time interval (frame), during which it is allowed to "broadcast". After one subscriber completes broadcasting, the resolution is interrupted by another, then the third, etc. After all subscribers are serviced, the process begins first. From the point of view of the subscriber, its activity is pulsing. The more subscribers, the less that each of them is given the opportunity to transfer their data, respectively, it will be able to transfer less data. If you limit the needs (possibilities) of the subscriber known value, you can estimate the number of users who will actually be able to serve the system with this method of separation of the medium. Temporary separation, as a rule, is superimposed on the frequency separation and broadcasting is carried out in the highlighted frequency band.

Among the three combined cellular standards, TDMA ranks second after the GSM standard occupies a dominant position in Europe. Although this standard in technological discussions is often not paid enough attention, the TDMA network continues to develop. Now they are used in 70 countries around the world and almost completely cover Northern and South America. The success of TDMAs is associated with the purity of voice reproduction, which is provided by the new Acelp voice encoder, dual-band and duplex telephones, increased capacity, global distribution and transition to the third-generation standard UWC-136. According to experts, the increase in the TDMA market (IS-136) reflects the accelerated transition to digital methods and the maturity of this technology. It is important that all three leading digital technologies will be able to become the basis for the third generation wireless communication services.

The development of a new pan-European standard of digital cellular bond began in 1985. Specially for this was created a special group - Group Special Mobile. Abbreviation GSM and gave the name to a new standard. Later GSM, due to its widespread, began to decrypt as Global System for Mobile Communications. To date, the GSM system has developed into the Global Second Generation Standard, which occupies the leading position in the world, both on the coating area and by the number of subscribers.

The GSM standard provides for the operation of transmitters in two frequency ranges: 890-915 MHz (for movable stations transmitters - MS), 935-960 MHz (for base stations transmitters - BTS).

The GSM standard uses narrow-band multiple access with temporal separation of channels (NB TDMA). The structure of the TDMA frame contains 8 time positions on each of the 124 carriers.

To protect against errors in radio channels, when transferring information messages, block and convolutional encoding with interleaving is used. Increasing the efficiency of encoding and interleaving at a low speed of moving moving stations is achieved by slow operating frequencies (SFH) during the communication session with a speed of 217 jumps per second.

To combat interference fading of received signals caused by the multipath propagation of radio waves in the conditions of the city, equalizers are used in communication equipment, providing alignment of pulse signals with a mean-square deviation of the delay time to 16 μs.

The synchronization system is designed to compensate for the absolute signal delay time up to 233 μs, which corresponds to the maximum range of communication or the maximum radius of the cell (honeycomb) 35 km.

Gaussian frequency manipulation with a minimum frequency shift (GMSK) is selected in the GSM standard. Speech processing is carried out within the framework of the received intermittent voice transmission system (DTX), which ensures the inclusion of the transmitter only if there is a speech signal and disabling the transmitter in pauses and at the end of the conversation. A speech codec with regular pulsed excitation / long-term prediction and linear predicative encoding (RPE / LTR-LTP-codec) is selected as a trichen-forming device. The total speed of transforming the speech, the signal is 13 kbps.

The GSM standard achieves a high degree of messaging security; The message encryption on the open key encryption algorithm (RSA) is being encrypted.

In general, the communication system operating in the GSM standard is designed to use it in various fields. It provides users with a wide range of services and the ability to apply a variety of equipment for transmitting voice messages and data, call and alarms; Connect to public telephone networks (PSTN), data transmission networks (PDN) and digital network integration (ISDN).

GSM 900 - Mobile Digital Standard, using the frequency range of 890 - 960 MHz. The GSM 900 standard is distributed in Europe, Asia, Russia and is used by the practical all modern European providers, but it is desirable that along with the GSM 900 apparatus support and the GSM 1800 standard, because In this case, when an interference occurs at a frequency of 900 MHz, the phone will be able to switch to the frequency of 1800 MHz.

GSM 1800 - Mobile Digital Standard, using a frequency range of 1710-1880 MHz. This standard is distributed in Europe, Russia, Australia, in Pacific countries of Asia. When buying a mobile phone, it is necessary to find out which standard local cellular operators work, because The GSM 1800 standard will not function in the GSM 900 network, and the GSM 900 standard is in the GSM 1800 network. Almost all modern providers in Europe use GSM 1800 and GSM 900 standards, so the most popular is the most popular are two-band telephone sets GSM 900/1800 - with Including such a phone itself for a fraction of a second determines at what frequency the signal is better, and configured on it.

GSM 1900 - Digital Mobile Standard, using the 1900 MHz frequency. This standard is common in the United States and Canada, so if you want to use the phone in these countries (provided that your cellular operator provides roaming services there), your device must support GSM 1900.

PDC (Personal Digital Cellular) is a cellular standard used in Japan.Standard is based on a three-shot TDMA solution. In this case, the carrier width is 25 kHz. Despite the fact that the PDC networks are located only in Japan, this standard confidently takes the second after the GSM position in the popularity peating among digital standards by the number of subscribers. And it is not surprising: in early 2000, the number of Cellular subscribers of Japan exceeded the number of subscribers of standard wired telephony. By the way, it is in Japan that the test sections of third-generation networks are already working - despite the rapid pace of cellular communication systems, the Japanese ahead of all the others for more than a year.

CDMA (Code Division Multiple Access) - a system of multiple access with code division - perhaps the most promising system that appears in the global market. Decades ago This technology was used in military communication (USA), and today is known to everyone as a global digital standard for commercial communication systems. Over the past five years, the CDMA technology has been tested, standardized, licensed and launched by most wireless equipment suppliers and is already applied worldwide. Unlike other methods of access to subscribers to the network, where the signal energy is concentrated at selected frequencies or time intervals, CDMA signals are distributed in continuous frequency-time space. In fact, the method manipulates the frequency, and time, and energy.

The CDMA technology it is possible to ensure high quality speech while reducing the radiated power and noise levels. The result is the constant high quality of voice and data transmission with minimal average output power.

A hundreds of times the smaller value of the output power, in contrast to the other standards currently used - the distinctive quality of CDMA technology when considering two important factors:
impact on the human body; Duration without recharging battery.

CDMA capacity from ten to twenty times higher than that of analog systems, and three to six times higher than the capacity of other digital systems. Networks built on its basis effectively use the radio frequency resource, due to the possibility of repeated use of the same frequencies on the network.

According to the characteristics of the quality of voice transmission, the CDMA parameters are comparable to the quality of wired channels. Since the CDMA channels are transmitted not only the voice, but any other information is given, the absence of noise has a special value. If the ordinary user, by and large, is indifferent to that, his voice sounds when a telephone conversation with impeccable cleanliness or with small interference, then errors made in transmitting files can disrupt integrity, such as a corporate database. The "code" used is not only for identifying a conversation of a user, but is both a kind of filter that eliminates distortion and background interference. The built-in coding algorithm provides a high degree of confidentiality, providing protection against unauthorized access and listening.

The CDMA system provides a smaller delay in voice messaging than other mobile communication systems. When using CDMA, it does not have to use sophisticated means for suppressing the echo signal. The perfect error correction method allows you to effectively deal with multipath signal propagation. This property provides additional advantages of CDMA in cities with high-altitude buildings.

The subscriber does not want to remain without communication when shipping fax when the phone is busy for a long time. CDMA provides an additional service providing simultaneous voice and fax transmission on one channel. In CDMA technology, original data packaging algorithms are implemented for greater speed of their transfer.

WCDMA (Wideband Code Division Multiple Access - Broadband CDMA) - Radio Interface Technology Selected by the Most Most Operators of the Japan Cell Communications and (in January 1988) Institute of ETSI to provide broadband radio access to support the third generation services.

Technology is optimized to provide high-speed multimedia types of video type, Internet access and video conferencing; Provides access speeds up to 2 Mbps at short distances and 384 kbps on large mobility. Such values \u200b\u200bof data transfer rates require a wide frequency band, therefore the WCDMA strip width is 5 MHz. The technology can be added to existing GSM and PDC networks, which makes the WCDMA standard most promising from the point of view of using network resources and global compatibility.

WCDMA (Broadband multiple access with coded channels) is a technology that uses an extended bandwidth and a variety of DMA principle. This is a third-generation mobile radio technology technology, providing significantly higher data transfer rates than GSM standard. WCDMA supports voice, image, data and videos in mobile networks at speeds up to 2 Mbps (local access) or 384 kbps (global access). WCDMA is used mainly in Europe when moving from the GSM standard to the UMTS standard.

The CDMaOne standard exists in the IS-95A, IS-95B variations (Cellular on American terminology, 800 MHz) and J-STD-008 (PCS, range 1900). IS Abbreviation (Interim Standard - Temporary Standard) is used to account for TIA telecommunication association (Telecommunications Industry Association). As a rule, IS-95A is used in CDMaOne networks, it provides a signal transmission at a speed of 9.6 kbps (with encoding) and 14.4 kbps (without coding). The IS-95B version is based on combining multiple CDMA channels organized in the forward direction (from the base station to mobile). The speed may increase to 28.8 kbps (with a combination of two channels of 14.4 kbps) or up to 115.2 kbps (8 channels of 14.4 kbps). Actually, in addition to the IS-95, the CDMaOEE network uses a whole set of protocols and standards.

CDMaOne commercial networks appeared in 1995 and enjoy well-deservedly popular both in their homeland in America and in Asia. It is CDMaOne that is meant under the terms "CDMA" and "CDMA-800" (the 800 meghertz version, IS-95 received the greatest distribution). Direct and reverse channels are located respectively in the ranges of 869.040-893,970 and 824,040-848,860 MHz. 64 Walsh codes and carriers at 1.25 MHz are used.

The CDMA2000 standard is the further development of the 2nd generation of CDMaOne. The further development of CDMaOne was to become an IS-95C, and this designation is very often used by manufacturers.

The official update of the standard developed by Qualcomm and Approved ITU (International Telecommunication Union, International Telecommunication Union) is CDMA2000. In documents Lucent Technologies occurs the designation IS-2000. Finally, the International Telecommunication Union (ITU) selected five-generation 3 IMT-2000 radio interfaces out of ten proposed projects (International Mobile Telecommunications System - 2000 - International Mobile System - 2000), among them - IMT-MC (Multi Carrier), which represents The modification of the CDMA2000 multi-frequency system, which provides backward compatibility with the equipment of the CDMaOne standard (IS-95).

Another five standards IMT-2000 - IMT-DS (Direct Spread) - built on the basis of WCDMA projects and taken as the basis of the European UMTS system.

At the beginning of 2003 Of the 127 million CDMA users, almost 15 million used CDMA2000 technology. During the first seven months of 2002, 11 CDMA2000 networks were launched in Asia and America and the total number of these networks was 18. This is 99% of the 3G market, IMT-MC accounted for 14.8 million subscribers, on UMTS - 0.13 million.

However, it is worth noting that the realized phase CDMA2000 1X is still not a full 3G, for it does not reach the mandatory two megabit. Therefore, it is more often called 2.5G.

Initially, CDMA2000 (IMT-MC) was divided into two phases - 1x and 3x. It is to the first phase that the name is-95c is applied. And the second later called 1x-EV (Evolution), separating it into two phases - CDMA2000 1X EV-Do (Data Only) and CDMA2000 1X EV-DV (Data & Voice).

And it is the standard CDMA2000 1X EV-DO that is meant under 3G IMT-MC. The 1x-EV-DO standard was adopted in October 2000 and provides for the following functioning scheme: The device simultaneously searches for a 1x and 1xEV network, data transmission exercises with 1xEV, voices with 1x.

The 1xEV-DV standard fully meets all 3G requirements. Its practical implementation is planned in 2003-2004.

Now about CDMA-450. It should be noted that the standards of the CDMA2000 family do not require the organization of a separate bandwidth and during their evolutionary development from CDMaOne can be implemented in all frequency ranges used by cellular mobile systems (450, 700, 800, 900, 1700, 1800, 1900, 2100 MHz ).

The network with packet data transmission - (General Packet Radio Service, GPRS) is a technology, standardized ETSI as part of the development of the GSM phase 2+ standard and representing the first implementation of batch switching in the GSM network networks previously used channel switching technology. Instead of transmitting a continuous data stream through a permanent connection, the network is used in packet switching only if there is data for transmission. The application of GPRS technology allows users to forward and receive data at speeds up to 170.2 kbps.

The introduction of GPRS technology brought significant benefits to operators of GSM networks. For the first time, the use of an IP Internet Protocol (Internet Protocol) was possible in GSM networks, as well as connecting to a huge number of private and public networks using standard data transmission protocols such as TCP / IP and X.25. The GPRS standard is especially effective in the scarcity of spectral resources, it allows GSM network operators to offer wide selection valuable opportunities, increasing their competitiveness.

GPRS is ideal for "pulse" data transmission applications, such as email or Internet access. It allows you to install a "virtual-permanent connection" with data sources, so you get the data, barely finding them. Such efficiency is achieved in channel switches. Introducing the GPRS standard, GSM operators have received the network with third-generation capabilities.

Motorola is different from other manufacturers by proclaiming the slogan "GPRS everywhere" - on the mass market for horizontal applications (for example, group interactive games), in the market of business applications for regular mobile vertical access to huge arrays of corporate information (for example, in delivery services).

Advanced Data Range For GSM Evolution, EDGE (Enhanced Datarate for GSM Evolution, EDGE), connects a set of new and alternative modulation schemes that can be used inside the GSM radio channel temporary segment structure, providing a higher data transfer rate or improved spectral characteristics. Phase 1 EDGE technology (standardized in late 1999) uses GPRS functions, providing data transfer speed up to 384 kbps. Phase 2 (must be developed until the end of 2000) provides real-time service, such as sound transmission and multimedia (video).

EDGE is implemented not only in the GSM environment, but also on the TDMA market (IS-136) and IDEN in the United States using the same technical standards to ensure the use of GPRS, and in the future - voice service. Since 384 kbps is a data transfer rate that will be supported by the first phase of third-generation networks, the EDGE can become an alternative for GSM operators that will not receive a third-generation license, or where it allows the regulator.

1xRTT (One Times Radio Transmission Technology) - 2.5G Mobile Digital Data Transmission Technology based on CDMA technology. Uses the principle of transmission with packet switching. Theoretically possible transfer rate is 144 kbps, but in practice the real speed is less than 40-60 kbps. 1xRTT uses a licensed radio frequency range and, like another mobile technologies, widespread.

UMTS is a universal mobile telecommunications system (Universal Mobile Telecommunications System) - is a member of the European Mobile Cell Family Standards Family. Most of the source tasks of UMTS, such as global roaming and service personalization, achieved during the development of the GSM standard. The main difference of UMTS is to use the new frequency range of 2 GHz, which makes it possible to achieve a higher quality of service compared to GSM due to an increase in the data transfer rate and channel capacity, as well as by implementing the network packet architecture that supports the voice and data transmission function.

UMTS provide two main components: radio network and carrier network. Radioset consists of mobile equipment and base station, between which data is switched. The carrier network, in turn, connects the basic stations with each other, and also creates connections to the ISDN network and the Internet.

With a significantly larger bandwidth (5 MHz) than the GSM (200 kHz) and using the CDMA method (Code Division Multiple Access), it becomes possible to transfer any type of information (multimedia applications, download from the Internet, video and audio) with high ( 2 Mbps) transmission rate.

This makes UMTS up to 200 times faster than the GSM network (9.6 kbps). This allows you to transfer 1-2 sources of real-time video with full resolution and acceptable quality.

An interesting feature regarding UMTS is not only that UMTS has a very high transmitting ability, but also that it also supports various transmission protocols, such as TCP / IP, in combination with mobility.

HSDPA (High Speed \u200b\u200bDownlink Packet Access) - high-speed batch access on the incoming channel. HSDPA technology is a logical continuation of WCDMA. The standard allows you to increase the data transfer rate in the 3G networks approximately for the same time as the EDGE technology deployed over the GPRS network. In absolute figures, the peak data transfer rate in the HSDPA network is 8 Mbps, while the average is 1-1.5 Mbps. For clarity it is worth saying that when peak performance on the HSDPA phone, eight digital movies can be watching.

Purpose of HSDPA - provide effective use of the radio frequency spectrum when providing services requiring high packet data transmission speeds on downward channels, such as Internet access and download files. This technology is well adapted to the conditions of the city and closed rooms.

The basis of HSDPA technology is based on adaptive modulation schemes and coding QPSK and 16 QAM; Repeatering protocol Hybrid Automatic Repeat Request; Operational definition of sequence of packet transmission at the Node base station in the Mac-High Speed \u200b\u200bprotocol. HSDPA is based on high-speed general downlink (High-Speed \u200b\u200bDownlink Shared Channel - HS-DSCH) capable of maintaining high data rates. Technology allows you to serve different users by multiplexing with temporary and code division, that is, ideal for processing intermittent batch traffic in a multiplayer environment.

Compared to UMTS, HSDPA can be transmitted three times more data and maintain twice as many mobile users per honeycomb. It is worth noting that at present, in the field, the speed in the downward channel 3G (to the user) is about 384 kbps (theoretically speed, according to the 3G specification, should be 2.4 Mbps).

In addition, HSDPA significantly improves the quality of the multimedia services to the subscriber (it is precisely due to a high speed, the delay becomes imperceptible, and the amount of information transmitted increases).

Similarly, high-speed UpLink Packet Access, HSUPA (HSUPA) technology is a mobile communication standard that allows you to speed up the transmission of data from the end-user W-CDMA devices to the base station by applying more advanced modulation methods.

Theoretically, the HSUPA standard is designed for the maximum data transfer rate in the direction of up to 5.8 Mbps, thus allowing the use of third-generation applications that require processing huge data streams from mobile device To the base station, for example, video conferencing.

Technology Description It is planned to enter as a specification of the 6th version of the 3GPP Release 6; The technology standardization process is approaching completion.

UNLICENSED Mobile Access is a new solution that allows subscriber devices to work on GSM / GPRS networks using unlicensed Bluetooth and Wi-Fi channels (802.11). Using UMA technology, operators can offer subscribers roaming and handover services between cellular networks and wireless unlicensed private and shared networks using duplex phones and PDAs.

UMA allows the user who has fallen into the coverage area of \u200b\u200bthe home or public access point ("hot spot"), to obtain high-quality communication services using a single access device and a single telephone number. As a result, we get a real convergence of services mobile transmission Voices and data with transparent handover (by passing a subscriber from one network to another without loss of connection).

EV-DO is a third-generation mobile network network technology (3G), standardized 3GPP2 as part of development and providing high-speed data transmission at a speed of up to 2.4 Mbps.

The advantages of EV-DO technology open a number of new features for users. In particular, a quick connection to the Internet, regardless of the location and time of day, the organization of high-speed corporate VPN networks, a wide range of mobile multimedia services, powerful tools for creating mobile "jobs". Corporate clients use EV-DO technology makes it possible to noticeably increase the productivity of employees due to widespread access at any time to corporate data with the help of protected and simple solutions, improve current business processes and build your business, as well as accelerate response to the problems of operation and customer issues.

To date, EV-DO technology is used in various fields: in banks and insurance companies, in distributional organizations and entrepreneurs who have trading networks, public authorities and users of home Internet as an alternative to the dedicated lines or Dial-Up.

Equipment manufacturers EV-DO networks are the leading world companies as Lucent Technologies, Huawei Technologies, Nortel Networks, Samsung. The Ukrainian operator running the EV-Do Standard is Peoplenet.

CSD (Circuit Switched Data) - Data transmission technology developed for GSM mobile phones. CSD uses one time interval for data transmission at a speed of 9.6 kbps in a network and switching subsystem (Network and Switching subsystem NSS), where they can be transmitted via the equivalent of a normal modem communication to the telephone network.

Since the maximum data transfer rate for a single time interval is 9.6 kbps, many operators allocate two or more time slots for CSD calls.

Before the CSD appears, data transmission in mobile phones was performed by using a modem or built into the phone or attached to it. Due to restrictions on the quality of the audio signal, such systems had the maximum data rate of 2.4 kbps. With the advent of digital data transmission in GSM, CSD provided practical direct access to the digital signal, allowing you to achieve higher speeds. At the same time, using a speech-oriented sound compression in GSM actually means that the data transfer rate using a normal modem connected to the phone will be even lower than in traditional analog systems.

CSD call works very similar to the usual voice call in GSM networks. A single time interval between the telephone and the base station is highlighted. The selected "critting interval" (16 Kbps) is set between the base station and the transcoder, and, finally, another time slot (64 kbps) is highlighted for data transmission between transcoder and switching center: Mobile Switching Center (MSC).

HSCSD (High Speed \u200b\u200bCircuit Switched Data - high-speed data transmission on channel switches) - multichannel data transfer platform in GSM networks. She overcomes restrictions wireless networks Speed \u200b\u200bcommunication, allowing GSM subscribers to transmit data with speeds comparable and even exceeding transmission rates in wired networks. When using HSCSD technology, the maximum speed may be 57.6 kbps. HSCSD is specifically designed for the development of an existing GSM infrastructure by upgrading software, so the implementation of this solution is made quickly and economically.

For end users, HSCSD opens up the possibility of using a number of new wireless communications applications. HSCSD allows you to view with a mobile terminal of a web page with a more rich graphic content. In addition, users are able to high-speed access to LAN and corporate networks.

HSCSD allows you to even organize a remote video surveillance in those places where the cable laying is inexpedient or impossible. It is necessary to mention the possibility of organizing video conferencing over a wireless interface.

HSPA (High-Speed \u200b\u200bPacket Access - high-speed data packet data) - wireless broadband radio communication technology using batch data transmission and is an add-in to WCDMA / UMTS mobile networks.
Technology is based on two preceding standards:
- - High-Speed \u200b\u200bDownlink Packet Access;
- - High-Speed \u200b\u200bUplink Packet Access.
At the moment, by Ericsson estimates, 128 HSPA networks are deployed in the world, and 300 devices with support for this technology are available on the market.

When choosing a gain system, it is extremely important to know two parameters: generation of a mobile network (2G, 3G or 4G), the quality of which you want to improve, and the frequency on which it functions.

The fact is that all the main components of amplification systems are antennas, repeaters, modems and routers are created under certain frequency ranges and very rarely support all the world's existing standards. In other words, you can purchase a gain "for 4G-Internet", but if it is an antenna, calculated on the frequency range in which your operator does not work, the money will be wasted.

Let us give an example. Most often 4G-Internet is provided at a frequency of 2600 MHz, and most of the sets for amplifying 4G are calculated on this frequency. Nevertheless, more and more often, domestic operators begin to use additional frequencies of 1800 and 800 MHz. If this network works in your location, the kit, calculated at the frequency of 2600 MHz, will be useless.

So, to choose a set, you need to know which technologies you want to strengthen and in what frequency bands they work. The easiest way to do this with a smartphone running operating system Android or iOS (iPhone).

Determine the generation of cellular network

Determine the generation of cellular network using a smartphone is usually very easy. In most modern operating systems, data transmission technology is indicated in the status bar next to the level of the cellular signal. The technology can be indicated directly (2G, 3G or 4G) or using one of the abbreviations. Most often are the following notation:

• 2G, GPRS (G), EDGE (E) - the traditional 2G technology on which the standard voice GSM communications and slow mobile Internet are working;
• 3G, UMTS, HSDPA (H), HSPA + (H +) - the third generation of cellular communication used for calls and access to broadband mobile Internet;
• 4G, LTE (L) is the fourth generation of cellular communication, in this moment Used domestic operators only to access high-speed mobile Internet.

For example, on Xiaomi smartphones with two SIM cards, the status bar is as follows:

How easy it is to determine the first SIM card of the MTS operator at the moment works in 4G mode, and the second SIM card Tele2 is in 3G.

What frequencies operators in Russia work

It would seem to know what communication standards are available at your location, you can proceed to the choice of the gain. Nevertheless, there is one significant problem: the same communication technology can work at different frequencies.

Each communication standard (2G, 3G and 4G) contains many submersions. In order for the gain system to work correctly and strengthened exactly the frequency range on which your operator works, this frequency range must be found.

Currently, the following cellular standards are found in Russia:

Generation	Frequency ranges	Name standard
		GSM-900, EGSM, GSM-E900
		GSM-1800, DCS-1800

Unfortunately, find out what frequency your operator works, is not so easy. The developers of Android and IOS operating systems considered that this information is not useful to normal users, and hid it into a special service menu. Below we will tell you how to call the hidden menu and find out the frequency used by the operator. But before that - one more important step!

If your smartphone defaults the network that you want to strengthen, additional actions are required. But there are situations where you need to determine the frequency range of another network. For example, you want to know the frequency of 2G, and the smartphone is automatically connected to 3G. Another example: you need to strengthen voice communicationAnd your phone is connected to a 4G network, which only mobile Internet is available. To measure the necessary standard, forcibly translate your smartphone to the appropriate mode.

To do this, on Android devices, go to Settings\u003e Other networks > Mobile networks > Network mode and select the required communication standard. Depending on the model of the smartphone and the version of the operating system, the path to the section Network mode May differ slightly.

Apple smartphones, unfortunately, do not support manual mode switching. Thus, iPhone users can determine the frequency of just the standard in which the smartphone works automatically.

How to find out a cellular frequency

As we have already told above, to get the frequency information on which your smartphone is connected to the base station, you need to go to a special service menu. On Android devices, it is commonly called Service Mode, on apple smartphones - Field Test. To call the appropriate screen, it is enough to dial a certain number from the phone.

Important! Depending on the device model and the operating system version, the instructions may not work in this article. In this case, entering the code will not lead to anything. Also on some smartphones, the menu may look different, and network information is in one of the submenu. You may have to search in the menu subsections before you find the right page with information about the mobile connection!

Before performing frequency test, disconnect the WiFi connection. In the event that two SIM cards are installed on your phone, it is recommended to extract an unnecessary card and leave only the one you want to test. So you can avoid unnecessary confusion and accurately get information about the current connection.

How to call a service menu on Android

Depending on the version of the Android, the service menu opens with one of the following codes:

• *#0011#
• *#*#4636#*#*
• *#*#197328640#*#*

After entering the last symbol, the hidden menu must open automatically, you do not need to press the call button. On Samsung smartphones you will immediately get on the screen with information about the status of the network. On devices of other manufacturers, you may need to go to the "Phone Information" or other subsection containing mobile connection information. Unfortunately, on some Android-smartphones models this menu It may not be available at all.

SAMSUNG smartphones for network information is enough to dial the number * # 0011

For information about the network on Xiaomi smartphones, you must dial the number * # * # 4636 # * # *, go to the "Phone Information" section and scroll down the page down. On devices with two SIM-card sections "Phone Information" will be two.

As you can see, the hidden menu provides a lot of technical data. We will not need much of this information, and what exactly should be paid attention to, we will tell you just below.

How to call a service menu on the iPhone

On Apple smartphones, the service menu is called in the same way, but using another code. After entering, you must click the call button:

• *3001#12345#*

To get information about cellular connection, you will need to find the right submenu item. Depending on the current communication standard, go through:

• for 2G: GSM Cell Environment > GSM Cell Info. > Neighboring Cells. > 0

• for 3G: Umts Cell Environment > NEIGHBOR CELLS. > UMTS SET. > 0

• for 4G: Serving Cell Info.

We define the frequency of the 2G network (GSM)

To determine the frequency on which the GSM network operates is used, the special radio frequency channel number is used - ArFCN. In fact, this identifier indicating that your smartphone is currently working in what radio frequency range. On the service menu page, the identifier is usually indicated after the designation ArfCN., RX, RX CH., Freq., BCCH or other similar abbreviation.

Less often smartphones in 2G mode show the name of the standard (for example, GSM-900) or operating frequency. If your smartphone displays the name of the standard in the finished form, consider what you are lucky. Otherwise, determine which standard specified ARFCN is related to the table below.

	2G standard	frequency range
0–124 975–1023

For example, it looks like a GSM frequency determination on Samsung smartphones (left) and iPhone (right):

If the smartphone shows several ARFCN values \u200b\u200blisted by the column, then the active network is usually the first in the list.

Determine the frequency of the 3G network

Similarly, the case is with the definition of frequency in 3G networks. Here the channel identifier is called differently - UARFCN. In contrast to 2G-networks, the UARFCN values \u200b\u200bcan be specified two: one to determine the data reception channel (DL), and the other indicating the sending channel (UL). The name of the standard or its special sequence number is indicated - the so-called "Band" (from English Band).

			3G standard	frequency range

Thus, in the service menu, you can detect either the value of UARFCN, or the BED's sequence number: for example, Band 1. UARFCN is usually indicated after such an abbreviation as RX, CH DL And others. On the iPhone, the 3G frequency identifier is called Downlink Frequency. or dL_FREQ..

If the smartphone shows several UARFCN values \u200b\u200blisted by the Stage, the active network is usually the first in the list.

We give an example of the definition of UARFCN on modern Xiaomi smartphones (left) and Samsung (right). In this case, the frequency is 2100 MHz:

We define the frequency of the 4G network

Similarly, the case is also with 4G-networks. Here, "Band" or channel identifier - EARFCN can be specified. On the iPhone, determine the frequency 4G is the easiest of the "Band" specified in paragraph Freq Band Indicatoror freq_band_ind.If the smartphone shows several EarFCN values \u200b\u200blisted by a column, then the active network is usually the first in the list.

			4G standard	frequency range

Please note that the latest above standard does not contain different EARFCN values \u200b\u200bfor sending and receiving. This is not at all by chance. The fact is that in the LTE Band 38 standard, the reception and data transfer occurs in the same frequency range, but alternately (TDD technology). To strengthen this standard, a special repeater may be required.

Below is an example of the EARFCN definition on Xiaomi smartphones (left) and recent versions iPhone (right).

On Android devices, it is possible to determine the 4G frequency and easier by using the free Cellmapper application. Cellmapper displays information about the cellular network, including the current "Band". Unfortunately, it is impossible to determine the frequency of 2G- or 3G networks.

Always define the frequency at that point in which you plan to install an external antenna of the amplification system. If the operator uses several frequency ranges at the same time, the smartphone can use one standard on the street, and the room is different. This is due to the fact that lower frequencies penetrate the premises better and, as a rule, it is them electronic devices Prefer.

For example, if your operator provides 4G-Internet simultaneously in frequency bands 800 and 2600 MHz, then the smartphone can choose a slower LTE800 standard, and on the street switch to faster LTE2600.

In addition, it should be borne in mind that the simultaneous use of two 4G-bands opens the possibility of frequency aggregation before the operator. Aggregation - LTE-Advanced network function, in which subscriber devices use several frequency ranges to achieve maximum speed. Today, this technology is just beginning to be introduced by cellular operators, but in the foreseeable future it can significantly increase the productivity of the mobile Internet.

If you have determined that in your location, the telecom operator works simultaneously in two "bandages", it makes sense to think about the acquisition of a dual-band gain system.

If we talk about mobile communications generations, then in Russia the most developed and widely represented 2G. The main standards of the second generation in the Russian Federation - GSM 900/1800 and CDMA 450. both GSM and CDMA are used for voice calls, text messages and mobile Internet access. Although the second generation cannot provide the same speeds as I say, 3G, or 4G, but this is the only type of cellular that is present in all regions Russian FederationEven in the most remote. The largest mobile providers on the territory of the Russian Federation are MegaFon, MTS, Beeline, VimpelCom and Tele2. On average, the coverage of the territory of the Russian Federation is 85%, but MTS, for example, provides a coverage of 100% of Russia.

(Click on the image to see it in full size)

The GSM standard in Russia uses frequencies of 900 and 1800 MHz. Since all mobile phones are duplex devices, two frequencies are used for communication, one for reception, the second for data transmission. By the way, these two frequencies are used to the cellular triangulation method. CDMA uses two frequencies in the ranges of 450 and 850 MHz, with the same duplex distribution. The largest CDMA provider is Skylink. As we have already noted, these standards are used mainly for voice calls, text messages and mobile Internet access. Internet access is implemented on GPRS and EDGE technologies.

The third generation of mobile communications or 3G, which is widely used throughout the world also presented in Russia. The largest 3G networks in the country work on WCDMA technology and according to the decision of the GCRC work at frequencies of 2000-2100 MHz. Under 3G should be understood 3G with all add-ons: HSUPA, HSPDA HSPA +, which are often mistakenly have like. Data transfer rates in such networks are incomparably higher than in the GSM network, and varies in the range of 2-14 Mbps. This generation of mobile communications allows us to enjoy fast mobile Internet and make video calls.

The largest operators of the 3G service market in Russia are MTS, MegaFon, VimpelCom, Beeline and Skylink. Together, these companies provide a 3G network in more than 120 largest cities of the Russian Federation. The third-generation network coverage is not as large and focused, mainly in densely populated cities. 3G is often used to organize hidden wireless video surveillance, as the transmission speed allows you to transmit streaming video, and low power consumption increases the operating time of the hidden camera. This partly explains popularity.

The fourth generation networks are also actively developing. The first companies that started the construction of such a network are Yota and Freshtel, after them in the development of this generation of communication in the territory of the Russian Federation such giants like MTS and MegaFon were included. Also in Russia was recently organized production facilities that develop and collect equipment for the base stations of the fourth generation, and also produce all the peripheral equipment necessary for this. The first city where the 4G network was launched was Novosibirsk, and after the fourth generation of mobile communications appeared in Moscow. 4G is represented by two standards - LTE (791-862 MHz) and Wi-Max (2500-2600 MHz). Today, the 4G network is fully deployed in such cities as: Moscow, St. Petersburg, Sochi, Samara, Novosibirsk, Ufa and Krasnodar.

Above the most common cellular standards, it is worth noting that the Russian Federation also created its global positioning system called. It was created in replacing the American satellite GPS navigation system. GLONASS is very different from GPS. The American system works on three channels and uses 3 different frequencies: 1575.42, 1227.60 and 1176.45 MHz, and is divided into civil and military sectors, and the frequency of 1575.42 MHz is assigned to the operation of the rescue service. GLONASS, in turn, works with two channels, their frequencies: 1602-1615 and 1246-1256 MHz. GLONASS is the most popular in the indoor regions, as the orbits of GLONASS satellites are higher than GPS orbits and have better visibility. However, it is worth noting that GPS defines the coordinates more precisely.

In general, it can be said that Russia has a good coverage of various standards and generations of cellular communication, and high rates cannot but please active users of mobile gadgets.

The beginners are incomprehensible to the games taken by the developers of standards. It would seem, uses GSM frequencies 850, 1900, 900, 1800 MHz, which is more like? Quick response - read the Network Telephone Instruction section. The unlawfulness of the generally accepted interpretation will be shown. The problem is described by the following provisions:

1. The second generation of 2G cellular communication has generated a lot of standards. The world knows three epicenter, asking Rhythm: Europe, North America, Japan. Russia adopted the standards of the first two, reinforcing.
2. The pedigree tree of standards is constantly carrying.
3. International standards options are designed to unite the heterogeneous rules of individual countries. Often it is impossible directly directly. Governments change the legislative base by fixing frequency plans.

This explains the origins of misunderstanding problems with beginners. Returning the subject of clarity, we will build a simplified hierarchy of standards, indicating the frequencies used passable.

Genealogy standards

The following information is designed to clarify the inhabitant the structure of existing, extinct standards. Below, in the following sections, technology used in Russia will be described. The corresponding representatives of the Tree, decorated Russian forest, are fed.

1G.

1. AMPS family: AMPS, NAMPS, TACS, ETACS.
2. Others: NMT, C-450, Datatac, Hicap, Mobitex.

2G: 1992.

1. GSM / 3GPP: GSM, HSCSD, CSD family.
2. Family 3GPP2: CDMaOne.
3. AMPS family: D-AMPS.
4. Other: IDEN, PHS, PDC, CDPD.

2G +.

1. Family 3GPP / GSM: GPRS, EDGE.
2. Family 3GPP2: CDMA2000 1X, including Advanced.
3. Others: Widen, DECT.

3G: 2003.

1. Family 3GPP: UMTS.
2. Family 3GPP2: CDMA2000 1xEV-Do R. 0

3G +.

1. Family 3GPP: LTE, HSPA, HSPA +.
2. Family 3GPP2: CDMA2000 1XEV-DO R. A, CDMA2000 1XEV-DO R. B, CDMA2000 1XEV-DO R. C
3. IEEE: Mobile WiMAX, Flash ofDM.

4G: 2013.

1. Family 3GPP: LTE-A, LTE-S Pro.
2. IEEE: WiMAX family.

5G: 2020.

1. 5G-Nr.

Short description

Genealogy allows you to trace extinct views. For example, modern authors often use GSM abbreviation, entering a deception reader. The technology is entirely limited by the second generation of cellular communication, extinct view. Former frequencies with additions continue to be used by descendants. On December 1, 2016, the Australian Tellest stopped using GSM, becoming the first operator in the world, entirely updating the equipment. The technology continues to be content with 80% of the world's population (according to GSM Association). An example of the Australian colleagues on January 1, 2017 was followed by American AT & T. The service stops the Optus operator, April 2017 Singapore, acknowledged 2G inconsistency with the increasing needs of the population.

So, the term GSM is used in relation to obsolete equipment, taking the Russian Federation. The descendant protocols can be called GSM heirs. The frequencies are saved by the following generations. Plugs are changing, information transfer methods. The aspects of the frequency distribution, accompanying the modernization of the equipment. Information is required to establish GSM kinship.

Telephone instruction

Useful information regarding the question will provide the phone instruction. The corresponding section lists the supported frequencies. Separate devices will allow you to adjust the reception area. You should choose a model of the phone, catching generally accepted Russian channels:

1. 900 MHz - E-GSM. Rising branch - 880..915 MHz, descending - 925..960 MHz.
2. 1800 MHz - DCS. Rising branch - 1710..1785 MHz, descending - 1805..1880 MHz.

LTE technology adds an area of \u200b\u200b2600 MHz, an 800 MHz canal is introduced.

History of the Communications RF: Frequency

In 1983, the development of the European Digital Standard was launched. We remind you, the first generation of 1G used analog transmission. Thus, engineers developed in advance the standard, proactive the history of the development of technology. Digital communication was born of World War II, more precisely, the cipher system was a green hornet. Military understood perfectly: the era is getting digital technology. Civil industry caught wind movement.

900 MHz

The European CEPT organization has created the GSM Committee (Groupe Special Mobile). The European Commission proposed to use the 900 MHz spectrum. The developers sat down in Paris. Five years later (1987), 13 EU countries filed Copenhagen Memorandum of the need to create a unified cellular network. The community decided to request GSM assistance. In February, the first technical specification came out. Policies of four countries (May 1987) supported the project by the Bonn Declaration. The next short period (38 weeks) is filled with universal bustle, controlled by four designated persons:

1. Armin Zilberhore (Germany).
2. Philip Dupulis (France).
3. Renzo Faili (Italy).
4. Stephen Temple (United Kingdom).

In 1989, the GSM commission leaves the CEPT guardianship, becoming part of ETSI. On July 1, 1991, the former Prime Minister of Finland, Harry Holzer, made the first call to the Subscriber (Kaararin Suonio), using the services of the Radio Provider.

1800 MHz

In parallel, the introduction of 2G was work designed to use the 1800 MHz region. The first network covered the United Kingdom (1993). At the same time, an Australian telecom operator was put on.

1900 MHz

The frequency of 1900 MHz was introduced by the United States (1995). A GSM Association has been created, a global number of subscribers has reached 10 million people. A year later, the figure has increased tenfold. The use of 1900 MHz prevented the introduction of the European version of UMTS.

800 MHz

The 800 MHz range appeared in 2002, in parallel to the implementation of the multimedia messaging service.

Attention, question!

What frequencies have become a Russian standard? Confusion adds ignorance by the authors of Runet standards taken by official developers. The direct response is discussed above (see the Telephone Instruction section), describe the work of the mentioned organizations (UMTS section).

Why so many frequencies

Exploring the results of 2010, the GSM Association said: 80% of the planet's subscribers are covered by the standard. This means that four fifths cannot choose a single frequency. In addition, there are 20% of alien communication standards. Where does the root of evil come from? The countries of the second half of the twentieth century developed fragmented. Frequencies 900 MHz USSR occupied military, civilian air navigation.

GSM: 900 MHz

In parallel to the development of the first variants of GSM NPO Astra, Radio Research Institute, the Research Institute of the Ministry of Defense, the studies ended with the internal tests. Received verdict:

• It is possible to jointly function navigation and second generation of cellular communication.

1. NMT-450.

Note: Again 2 Standards. Each uses its own frequency grid. The announced competition of the GSM-900 distribution won NPO Astra, MGTS OJSC (now MTS), Russian companies, Canadian BCeti.

NMT-450MHz - the first generation

So, Moscow used, since 1992, the range of 900 MHz (see above), because other GSM frequencies have not yet been born. In addition to NMT (Nordic mobile phones) ... Initially, the countries of the Scandinavian Peninsula have developed two options:

1. NMT-450.
2. NMT-900 (1986).

Cause of choice by the Russian government of the first answer? Probably decided to try two ranges. Please note the specified standards describe analogue link (1G). The developers countries began to cover the shop from December 2000. The latter (September 1, 2010) surrendered to Iceland (Siminn). Experts note an important advantage of a range of 450 MHz: range. Weighing plus, appreciated by remote Iceland. The Russian government wanted to cover the country area, using the minimum of the highest.

NMT loved fishermen. The liberated grid took digital CDMA 450. For 2015, Scandinavia technology mastered 4G. Russian Uralvestian released the Camork on September 1, 2006, Sibirtelecom - January 10, 2008. The child's subsidiary (body 2) scores the Perm region, Arkhangelsk region. The deadline for the end of the license is 2021.

D-amps: DMW (400..890 MHz) - second generation

American networks 1G, used AMPS specification, refused to receive GSM. Instead, two alternatives have been developed to organize second-generation mobile networks:

1. IS-54 (March 1990, 824-849; 869-894 MHz).
2. IS-136. Differs in a large number of channels.

The standard is now dead, universally replaced by the descendants of GSM / GPRS, CDMA2000.

Why do Russian D-amps

The Russian manual often uses used appliances. D-AMPS equipment has reached the warehouses of the body 2, Beeline. November 17, 2007 Latest covered the center of the central region. The license of the Novosibirsk region expired on December 31, 2009. The last swallow flew on October 1, 2012 (Kaliningrad region). Kyrgyzstan used range until March 31, 2015.

CDMA2000 - 2G +

Some protocol variants are used:

1. Uzbekistan - 450 MHz.
2. Ukraine - 450; 800 MHz.

In the period December 2002 - October 2016 Specifications 1хRTT, EV-DO Rev. A (450 MHz) was used skype. Now the infrastructure is upgraded, LTE is implemented. On September 13, 2016, world portals had the news: Tele 2 stops using CDMA. American MTS began the process of introducing LTE a year earlier.

GPRS - second-third generation

The development of the CellPac protocol (1991-1993) was a turning point of cellular development. Received 22 US patent. The descendants of technology consider LTE, UMTS. Batch data transfer is designed to speed up the information exchange process. The project is intended to improve the GSM network (frequencies are listed above). The user is obliged to obtain technologies:

1. Access to the Internet.
2. Outdated "Click to talk."
3. Messenger.

The overlays of two technologies (SMS, GPRS) explicitly accelerates the process. The specification supports IP, PPP, X.25 protocols. Packages continue to come even during a conversation.

Edge.

The next stage of the Evolution of GSM is conceived by AT & T companies (USA). Compact-edge took a niche d-amps. Frequencies are listed above.

UMTS - Full 3G

The first generation required to update the equipment of base stations. The frequency grid has changed. The limit transmission rate of the line using the advantages of HSPA + is 42 Mbps. Really achievable speeds are significantly overlapped with 9.6 Kbps GSM. Since 2006, countries have started updating. Using orthogonal frequency multiplexing, the 3GPP committee intended to reach 4G. Early birds were released in 2002. Initially, the developer laid the following frequencies:

1. .2025 MHz. Rising connected branch.
2. .2200 MHz. Downward connected branch.

Since the United States has already used 1900 MHz, then selected segments 1710..1755; 2110..2155 MHz. Many countries followed the example of America. The frequency of 2100 MHz is too often busy. From here, the numbers at first:

• 850/1900 MHz. Moreover, 2 channels are chosen using one range. Either 850 or 1900.

Agree, it is incorrect to ship GSM, following a bad spread example. The second generation used a half-duplex single channel, UMTS - used two (5 MHz width) at once.

UMTS Frequency Grid

The first attempt to distribute the spectra took place on February 3 to March 3, 1992. The decision has adapted the Geneva Conference (1997). It is the S5.388 specification that secured the ranges:

• 1885-2025 MHz.
• 2110-2200 MHz.

The decision demanded further refinements. The Commission identified 32 ultra-channel, 11 amounted to an unused reserve. Most others received clarifying names, since individual frequencies coincided. Russia has rejected European practices, despusting the United States, accepting 2 channels (Band) UMTS-FDD:

1. №8. 900 MHz - E-GSM. Rising branch - 880..915 MHz, descending - 925..960 MHz.
2. Number 3. 1800 MHz - DCS. Rising branch - 1710..1785 MHz, descending - 1805..1880 MHz.

Characteristics cell phone It should be chosen according to the information provided. Wikipedia Table, revealing frequency plan of the planet Earth, is completely useless. Forgot to take into account the Russian specifics. Europe operates nearby channel №1 IMT. In addition, there is a UMTS-TDD grid. The equipment of two air network options are incompatible.

LTE - 3G +

Evolutionary continuation of the GSM-GPRS-UMTS bundle. May serve as an add-on CDMA2000 networks. Only a multi-frequency phone is able to provide LTE technology. Experts directly indicate the place below the fourth generation. Rotating statements of marketers. Initially, the ITU-R organization recognized the technology of the appropriate, later the position was revised.

LTE are a registered trademark ETSI. The key idea was the use of signal processors and the introduction of innovative modulation methods of carrier. The appropriate IP addressing of subscribers was recognized. The interface lost backward compatibility, the frequency spectrum has once changed. The first grid (2004) is launched by the Japanese company NTT Docomo. Moscow The exhibition version of technology will overtake in 2010.

Repeating UMTS experience, the developers have introduced two options for the air Protocol:

1. LTE-TDD. Temporary division of channels. Technology is widely supported by China, South Korea, Finland, Switzerland. The presence of a single frequency channel (1850..3800 MHz). Partially overlaps WiMAX, an upgrade is possible.
2. LTE-FDD. Frequency division of channels (separate downward, ascending).

Frequency plans 2 technologies are different, 90% of the kernel design coincides. Samsung, Kluckoms produce phones capable of catching both protocols. Ranges occupied:

1. North America. 700, 750, 800, 850, 1900, 1700/2100, 2300, 2500, 2600 MHz.
2. South America. 2500 MHz.
3. Europe. 700, 800, 900, 1800, 2600 MHz.
4. Asia. 800, 1800, 2600 MHz.
5. Australia, New Zealand. 1800, 2300 MHz.

Russia

Russian operators have chosen LTE-FDD technology, use frequencies:

1. 800 MHz.
2. 1800 MHz.
3. 2600 MHz.

LTE-A - 4G

Frequencies remained the same (see LTE). Launch chronology:

1. On October 9, 2012, Yota appeared 11 base stations.
2. MegaFon February 25, 2014 covered the garden ring of the capital.
3. Beeline from August 5, 2014 operates at LTE 800 frequencies, 2600 MHz.

DOWNLINK - Channel of communication from the base station to the subscriber
UPLink - communication channel from the subscriber to the base station of the operator.

4G / LTE standard frequency 2500

This type of communication is relatively recently developing and mainly in cities.

FDD (Frequency Division Duplex - Frequency Separation of Channels) - this is DownLink and Uplink work on different frequency bands.
TDD (Time Division Duplex - temporary channel separation) is DownLink and Uplink work on the same frequency band.

Yota: FDD DOWNLINK 2620-2650 MHz, UPLINK 2500-2530 MHz
MegaFon: FDD DOWNLINK 2650-2660 MHz, UPLINK 2530-2540 MHz
MegaFon: TDD 2575-2595 MHz - This frequency band is highlighted only in the Moscow region.
MTS: FDD DOWNLINK 2660-2670 MHz, UPLINK 2540-2550 MHz
MTS: TDD 2595-2615 MHz - This frequency band is highlighted only in the Moscow region.
Beeline: FDD DOWNLINK 2670-2680 MHz, uplink 2550-2560 MHz
Rostelecom: FDD DOWNLINK 2680-2690 MHz, UPLINK 2560-2570 MHz
After buying a Yota Megaphone, Yota virtually began to work as a megaphone.

4G / LTE standard frequency 800

In commercial operation, the network was launched in early 2014, mainly outside the city, in rural areas.

UPLINK / DOWNLINK (MHz)

Rostelecom: 791-798,5 / 832 - 839.5
MTS: 798.5-806 / 839,5 - 847.5
MegaFon: 806-813,5 / 847 - 854.5
Beeline: 813,5 - 821 / 854,5 - 862

3G / UMTS Standard Frequency 2000

3G / UMTS2000 - the most common cellular standard in Europe is mainly used to transfer data.

UPLINK / DOWNLINK (MHz)

Skylink: 1920-1935 / 2110 - 2125 - Ultimately, the most likely these frequencies will fly out Rostelek. At the moment, the network is not used.
MegaFon: 1935-1950 / 2125 - 2140
MTS: 1950-1965 / 2140 - 2155
Beeline: 1965 - 1980/2155 - 2170

2G / DCS Standard Frequency 1800

DCS1800 is the same GSM, only in another frequency range, is preistently used in cities. But, for example, there are regions where tele2 operator operator only works in the 1800 MHz band.

UPLINK 1710-1785 MHz and DownLink 1805-1880 MHz

Show division according to the operators there is no sense, because In each region, the frequency distribution is individual.

Standard 2G / DCS Frequency 900

GSM900 is the most common communication standard in Russia today and is considered a second generation bond.

There are 124 channels in the GSM900 MHz. In all regions of the Russian Federation, GSM frequency bands are distributed between operators individually. And there exists an E-GSM as an additional frequency range GSM. It is shifted by the frequency of the currently basic on 10 MHz ..

Uplink 890-915 MHz and DOWNLINK 935-960 MHz

UPLINK 880-890 MHz and DownLink 925-935 MHz

Standard 3G Frequency 900

Due to the lack of channels in 2000 frequency, the frequencies of 900 MHz were isolated under 3G. Actively used in the area.

CDMA Standard Frequency 450

CDMA450 - In the central part of Russia, this standard uses only Skylink operator (Skylink).

UPLINK 453 - 457.5 MHz and DownLink 463 - 467.5 MHz.