The principle of operation of cellular communications. How to choose a mobile operator? Mobile cells

cellular

cellular, mobile network- one of the types of mobile radio communications, which is based on cellular network. Key Feature lies in the fact that the total coverage area is divided into cells (cells), determined by the coverage areas of individual base stations (BS). The cells partially overlap and together form a network. On an ideal (flat and undeveloped) surface, the coverage area of ​​one BS is a circle, so the network made up of them looks like a honeycomb with hexagonal cells (honeycombs).

The network consists of spatially dispersed transceivers operating in the same frequency range, and switching equipment that makes it possible to determine the current location of mobile subscribers and ensure continuity of communication when a subscriber moves from the coverage area of ​​one transceiver to the coverage area of ​​another.

Story

The first use of mobile telephone radio in the United States dates back to 1921: Detroit police used one-way dispatch communications in the 2 MHz band to transmit information from a central transmitter to vehicle-mounted receivers. In 1933, the NYPD began using a two-way mobile telephone radio system, also in the 2 MHz band. In 1934, the US Federal Communications Commission allocated 4 channels for telephone radio communications in the range of 30-40 MHz, and in 1940 about 10 thousand police vehicles were already using telephone radio communications. All of these systems used amplitude modulation. Frequency modulation began to be used in 1940 and by 1946 it had completely replaced amplitude modulation. The first public mobile radiotelephone appeared in 1946 (St. Louis, USA; Bell Telephone Laboratories), it used the 150 MHz band. In 1955, an 11-channel system began operating in the 150 MHz band, and in 1956, a 12-channel system in the 450 MHz band began operating. Both of these systems were simplex and used manual switching. Automatic duplex systems began operating in 1964 (150 MHz) and 1969 (450 MHz), respectively.

In the USSR in 1957, Moscow engineer L.I. Kupriyanovich created a prototype of a portable automatic duplex mobile radiotelephone LK-1 and a base station for it. The mobile radiotelephone weighed about three kilograms and had a range of 20-30 km. In 1958, Kupriyanovich created improved models of the device, weighing 0.5 kg and the size of a cigarette box. In the 1960s Hristo Bochvarov in Bulgaria demonstrates his prototype of a pocket mobile radiotelephone. At the Interorgtekhnika-66 exhibition, Bulgaria is presenting a kit for organizing local mobile communications from pocket mobile phones RAT-0.5 and ATRT-0.5 and a base station RATC-10, providing connection for 10 subscribers.

At the end of the 50s in the USSR, the development of the Altai car radiotelephone system began, which was put into trial operation in 1963. The Altai system initially operated at a frequency of 150 MHz. In 1970, the Altai system operated in 30 cities of the USSR and the 330 MHz range was allocated for it.

In a similar way, with natural differences and on a smaller scale, the situation developed in other countries. Thus, in Norway, public telephone radio has been used for maritime mobile communications since 1931; in 1955 there were 27 coast radio stations in the country. Ground mobile connection began to develop after the Second World War in the form of private networks with manual switching. Thus, by 1970, mobile telephone radio communications, on the one hand, had already become quite widespread, but on the other, it clearly could not keep up with the rapidly growing needs, with a limited number of channels in strictly defined frequency bands. A solution was found in the form of a cellular communication system, which made it possible to dramatically increase capacity by reusing frequencies in a system with a cellular structure.

Cellular systems

Certain elements of the cellular communication system existed before. In particular, some semblance of a cellular system was used in 1949 in Detroit (USA) by a taxi dispatch service - with the reuse of frequencies in different cells when users manually switched channels at predetermined locations. However, the architecture of what is now known as the cellular communications system was not outlined until the Bell System technical report submitted to the FCC in December 1971. From this time on, the development of cellular communications itself began.

In 1974, the US Federal Communications Commission decided to allocate a frequency band of 40 MHz in the 800 MHz band for cellular communications; in 1986 another 10 MHz was added in the same range. In 1978, tests of the first experimental cellular communication system for 2 thousand subscribers began in Chicago. Therefore, 1978 can be considered the year of the beginning of the practical use of cellular communications. The first automated commercial cellular telephone system was introduced in Chicago in October 1983 by American Telephone and Telegraph (AT&T). In Canada, cellular communications have been used since 1978, in Japan - since 1979, in northern European countries (Denmark, Norway, Sweden, Finland) - since 1981, in Spain and England - since 1982. As of July 1997 cellular communications operated in more than 140 countries on all continents, serving more than 150 million subscribers.

The first commercially successful cellular network was the Finnish Autoradiopuhelin (ARP) network. This name is translated into Russian as “Car radiotelephone”. Launched in 1971, it reached 100% coverage in Finland in 1978, and in 1986 it had more than 30 thousand subscribers. The network operated at a frequency of 150 MHz, the cell size was about 30 km.

Operating principle of cellular communication

The main components of a cellular network are cell phones and base stations, which are usually located on the roofs of buildings and towers. Being turned on cellular telephone listens to the airwaves, finding the signal from the base station. The phone then sends its unique identification code to the station. The telephone and the station maintain constant radio contact, periodically exchanging packets. Communication between the phone and the station can be via an analog protocol (AMPS, NAMPS, NMT-450) or digital (DAMPS, CDMA, GSM, UMTS). If the phone leaves the range of the base station (or the quality of the radio signal from the service cell deteriorates), it establishes communication with another one. handover).

Cellular networks can consist of base stations of different standards, which allows optimizing network operation and improving its coverage.

Cellular networks different operators connected to each other, as well as to the landline telephone network. This allows subscribers of one operator to make calls to subscribers of another operator, from mobile phones to landlines and from landlines to mobiles.

Operators can enter into roaming agreements among themselves. Thanks to such agreements, a subscriber, being outside the coverage area of ​​his network, can make and receive calls through the network of another operator. As a rule, this is carried out at increased rates. The possibility of roaming appeared only in 2G standards and is one of the main differences from 1G networks.

The head of the Regional Journalism Club, Irina Yasina, recalls:

By July 1997, the total number of subscribers in Russia was about 300 thousand. As of 2007, the main cellular communication protocols used in Russia are GSM-900 and GSM-1800. In addition, CDMA networks also operate in the CDMA-2000 standard, also known as IMT-MC-450. GSM operators are also making a smooth transition to the UMTS standard. In particular, the first fragment of a network of this standard in Russia was put into operation on October 2, 2007 in St. Petersburg by MegaFon.

The IDC company, based on a study of the Russian cellular communications market, concluded that in 2005 the total duration of calls on a cell phone by residents of the Russian Federation reached 155 billion minutes, and 15 billion text messages were sent.

According to data from the British research company Informa Telecoms & Media for 2006, the average cost of a minute of cellular communication for a consumer in Russia was $0.05 - this is the lowest among the G8 countries.

In December 2007, the number of cellular users in Russia increased to 172.87 million subscribers, in Moscow - to 29.9, in St. Petersburg - to 9.7 million. Penetration level in Russia - up to 119.1%, Moscow - 176%, St. Petersburg - 153%. In December 2011, the penetration level in Russia was up to 156%, Moscow - 212.1%, St. Petersburg - 215.6%. The market share of the largest cellular operators as of December 2007 was: MTS 30.9%, VimpelCom 29.2%, MegaFon 19.9%, other operators 20%.

According to a study by J"son & Partners, the number of SIM cards registered in Russia as of the end of November 2008 reached 183.8 million. This figure is due to the lack of subscription fees on popular tariff plans from Russian cellular operators and the low cost of connecting to the network In some cases, subscribers have SIM cards from different operators, but may not use them for a long time, or use one SIM card in a business mobile phone and the other for personal conversations.

In Russia in December 2008, there were 187.8 million cellular users (based on the number of SIM cards sold). The penetration rate of cellular communications (the number of SIM cards per 100 inhabitants) on this date was thus 129.4%. In the regions, excluding Moscow, the penetration level exceeded 119.7%.

The penetration level at the end of 2009 reached 162.4%.

As of April 2010, market share in Russia by subscribers: MTS - 32.9%, MegaFon - 24.6%, VimpelCom - 24.0%, Tele2 - 7.5%, other operators - 11.0%

Cellular services

Mobile operators provide the following services:

• Voice call;
• Caller ID (Automatic Caller ID) and Anti-Caller ID;
• Reception and transmission of multimedia messages - images, melodies, videos (MMS service);
• Access to the Internet ;
• Video call and video conference

see also

Notes

Links

• The basis of a cellular network - how base stations are built - review article on the website 3Dnews.ru (Russian)
• Cellular Communications Control Center - a view from the inside - review article on the website 3Dnews.ru (Russian)
• MAIN INDICATORS OF THE DEVELOPMENT OF PUBLIC TELEPHONE COMMUNICATIONS AND MOBILE COMMUNICATIONS (at the end of 2009)

cellular in Russia
Operators
...virtual
Sales networks
Standards

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See what “Cellular communications” is in other dictionaries:

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One of the types of mobile radio communications, which is based on a cellular network. The key feature is that the total coverage area is divided into cells (cells), determined by the coverage areas of individual base stations (BS). Honeycombs partially... ... Dictionary of business terms

Third generation cellular communications- Third generation cellular networks (3rd Generation, or 3G) operate at frequencies in the range of about 2 gigahertz and provide data transmission at speeds of up to 2 megabits per second. Such characteristics allow you to use a mobile phone in... ... Encyclopedia of Newsmakers

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The article contains errors and/or typos. It is necessary to check the content of the article for compliance with the grammatical norms of the Russian language... Wikipedia

mobile connection- this is radio communication between subscribers, the location of one or more of which changes. One type of mobile communication is cellular communication.

cellular- one of the types of radio communications, which is based on a cellular network. Key Feature: The total coverage area is divided into cells determined by coverage areas base stations. The cells overlap and together form a network. On an ideal surface, the coverage area of ​​one base station is a circle, so the network made up of them looks like cells with hexagonal cells.

Operating principle of cellular communication

So, first, let's look at how a call is made on a mobile phone. As soon as the user dials a number, the handset (HS - Hand Set) begins searching for the nearest base station (BS - Base Station) - the transceiver, control and communication equipment that makes up the network. It consists of a base station controller (BSC - Base Station Controller) and several repeaters (BTS - Base Transceiver Station). Base stations are controlled by a mobile switching center (MSC - Mobile Service Center). Thanks to the cellular structure, repeaters cover the area with a reliable reception area in one or more radio channels with an additional service channel through which synchronization occurs. More precisely, the exchange protocol between the device and the base station is agreed upon by analogy with the modem synchronization procedure (handshacking), during which the devices agree on the transmission speed, channel, etc. When the mobile device finds a base station and synchronization occurs, the base station controller forms a full-duplex link to the mobile switching center through the fixed network. The center transmits information about the mobile terminal to four registers: the Visitor Layer Register (VLR), the Home Register Layer (HRL), and the Subscriber or Authentication Register (AUC). and equipment identification register (EIR - Equipment Identification Register). This information is unique and is located in the plastic subscription box. microelectronic telecard or module (SIM - Subscriber Identity Module), which is used to check the subscriber’s eligibility and tariffication. Unlike landline phones, for the use of which you are charged depending on the load (the number of busy channels) coming through a fixed subscriber line, the fee for using mobile communications is not charged from the telephone used, but from the SIM card, which can be inserted into any apparatus.

The card is nothing more than a regular flash chip, made using smart technology (SmartVoltage) and having the necessary external interface. It can be used in any device, and the main thing is that the operating voltage matches: early versions used a 5.5V interface, while modern cards usually have 3.3V. The information is stored in the standard of a unique international subscriber identifier (IMSI - International Mobile Subscriber Identification), which eliminates the possibility of "doubles" - even if the card code is accidentally selected, the system will automatically exclude the fake SIM, and you will not have to subsequently pay for other people's calls. When developing the cellular communication protocol standard, this point was initially taken into account, and now each subscriber has its own unique and only identification number in the world, encoded during transmission with a 64-bit key. In addition, by analogy with scramblers designed to encrypt/decrypt conversations in analogue telephony, 56-bit coding is used in cellular communications.

Based on this data, the system’s idea of ​​the mobile user is formed (his location, status on the network, etc.) and the connection occurs. If during a conversation a mobile user moves from the coverage area of ​​one repeater to the coverage area of ​​another, or even between the coverage areas of different controllers, the connection is not interrupted or deteriorated, since the system automatically selects the base station with which the connection is better. Depending on the channel load, the phone selects between a 900 and 1800 MHz network, and switching is possible even during a conversation, completely unnoticed by the speaker.

A call from a regular telephone network to a mobile user is made in the reverse order: first, the location and status of the subscriber are determined based on constantly updated data in the registers, and then the connection and communication are maintained.

Mobile radio communication systems are built according to a point-multipoint scheme, since the subscriber can be located at any point in the cell controlled by the base station. In the simplest case of circular transmission, the power of a radio signal in free space theoretically decreases in inverse proportion to the square of the distance. However, in practice, the signal attenuates much faster - in the best case, proportional to the cube of the distance, since the signal energy can be absorbed or reduced by various physical obstacles, and the nature of such processes strongly depends on the transmission frequency. When the power decreases by an order of magnitude, the covered area of ​​the cell decreases by two orders of magnitude.

"PHYSIOLOGY"

The most important reasons for increased signal attenuation are shadow areas created by buildings or natural elevations in the area. Studies of the conditions for the use of mobile radio communications in cities have shown that even at very close distances, shadow zones provide attenuation of up to 20 dB. Another important cause of attenuation is tree foliage. For example, at a frequency of 836 MHz in the summer, when the trees are covered with leaves, the received signal level is approximately 10 dB lower than at the same place in the winter, when there are no leaves. The fading of signals from shadow zones is sometimes called slow in terms of the conditions for their reception in motion when crossing such a zone.

An important phenomenon that has to be taken into account when creating cellular mobile radio communication systems is the reflection of radio waves, and, as a consequence, their multipath propagation. On the one hand, this phenomenon is useful, since it allows radio waves to bend around obstacles and propagate behind buildings, in underground garages and tunnels. But on the other hand, multipath propagation gives rise to such difficult problems for radio communications as extended signal delay, Rayleigh fading and worsening of the Doppler effect.

Signal delay stretching occurs due to the fact that a signal passing along several independent paths of different lengths is received several times. Therefore, a repeated pulse can go beyond the time interval allotted for it and distort the next character. Distortion caused by extended delay is called intersymbol interference. At short distances, the extended delay is not dangerous, but if the cell is surrounded by mountains, the delay can extend for many microseconds (sometimes 50-100 μs).

Rayleigh fading is caused by the random phases with which the reflected signals arrive. If, for example, the direct and reflected signals are received in antiphase (with a phase shift of 180°), then the total signal can be attenuated almost to zero. Rayleigh fading for a given transmitter and a given frequency is something like amplitude “dips” that have different depths and are distributed randomly. In this case, with a stationary receiver, fading can be avoided simply by moving the antenna. When a vehicle is moving, thousands of such “dips” occur every second, which is why the resulting fading is called fast.

The Doppler effect manifests itself when the receiver moves relative to the transmitter and consists of a change in the frequency of the received oscillation. Just as the pitch of a moving train or car appears slightly higher to a stationary observer as the vehicle approaches and slightly lower as it moves away, the frequency of a radio transmission shifts as the transceiver moves. Moreover, with multipath signal propagation, individual rays can produce a frequency shift in one direction or another at the same time. As a result, due to the Doppler effect, random frequency modulation of the transmitted signal is obtained, just as random amplitude modulation occurs due to Rayleigh fading. Thus, in general, multipath propagation creates great difficulties in organizing cellular communications, especially for mobile subscribers, which is associated with slow and fast fading of the signal amplitude in a moving receiver. These difficulties were overcome with the help of digital technology, which made it possible to create new methods of coding, modulation and equalization of channel characteristics.

"ANATOMY"

Data transmission is carried out via radio channels. The GSM network operates in the 900 or 1800 MHz frequency bands. More specifically, for example, in the case of considering the 900 MHz band, the mobile subscriber unit transmits on one of the frequencies lying in the range 890-915 MHz, and receives on a frequency lying in the range 935-960 MHz. For other frequencies the principle is the same, only the numerical characteristics change.

By analogy with satellite channels, the direction of transmission from the subscriber device to the base station is called upward (Rise), and the direction from the base station to the subscriber device is called downward (Fall). In a duplex channel consisting of upstream and downstream transmission directions, frequencies differing by exactly 45 MHz are used for each of these directions. In each of the above frequency ranges, 124 radio channels are created (124 for receiving and 124 for transmitting data, spaced at 45 MHz) with a width of 200 kHz each. These channels are assigned numbers (N) from 0 to 123. Then the frequencies of the upstream (F R) and downstream (F F) directions of each channel can be calculated using the formulas: F R (N) = 890+0.2N (MHz), F F (N) = F R (N) + 45 (MHz).

Each base station can be provided with from one to 16 frequencies, and the number of frequencies and transmission power are determined depending on local conditions and load.

In each of the frequency channels, which is assigned a number (N) and which occupies a 200 kHz band, eight time division channels (time channels with numbers from 0 to 7), or eight channel intervals, are organized.

The frequency division system (FDMA) allows you to get 8 channels of 25 kHz, which, in turn, are divided according to the principle of the time division system (TDMA) into another 8 channels. GSM uses GMSK modulation and the carrier frequency changes 217 times per second to compensate for possible quality degradation.

When a subscriber receives a channel, he is allocated not only a frequency channel, but also one of the specific channel slots, and he must transmit in a strictly allotted time interval, without going beyond it - otherwise interference will be created in other channels. In accordance with the above, the transmitter operates in the form of individual pulses, which occur in a strictly designated channel interval: the duration of the channel interval is 577 μs, and the duration of the entire cycle is 4616 μs. Allocation to the subscriber of only one of the eight channel intervals allows the process of transmission and reception to be divided in time by shifting the channel intervals allocated to the transmitters of the mobile device and the base station. The base station (BS) always transmits three timeslots before the mobile unit (HS).

The requirements for the characteristics of a standard pulse are described in the form of a normative pattern of changes in radiation power over time. The processes of turning the pulse on and off, which are accompanied by a change in power by 70 dB, must fit into a time period of only 28 μs, and the working time during which 147 binary bits are transmitted is 542.8 μs. The transmission power values ​​​​indicated in the table earlier refer specifically to the pulse power. The average power of the transmitter turns out to be eight times less, since the transmitter does not radiate 7/8 of the time.

Let's consider the format of a normal standard pulse. It shows that not all discharges carry useful information: Here, a 26-bit training sequence is placed in the middle of the pulse to protect the signal from multipath interference. This is one of eight special, easily recognizable sequences in which the received bits are correctly positioned in time. Such a sequence is fenced with single-bit pointers (PB - Point Bit), and on both sides of this training sequence there is useful encoded information in the form of two blocks of 57 binary bits, fenced, in turn, with boundary bits (BB - Border Bit) - 3 bits each each side. Thus, a pulse carries 148 bits of data, which takes up a 546.12 µs time interval. To this time is added a period equal to 30.44 μs of protective time (ST - Shield Time), during which the transmitter is “silent”. In terms of duration, this period corresponds to the time of transmission of 8.25 bits, but no transmission occurs at this time.

The sequence of pulses forms a physical transmission channel, which is characterized by a frequency number and a time channel slot number. Based on this sequence of pulses, a whole series of logical channels are organized, which differ in their functions. In addition to channels transmitting useful information, there are also a number of channels transmitting control signals. The implementation of such channels and their operation require precise management, which is implemented by software.

Do you know what happens after you dial a friend's number on your mobile phone? How does the cellular network find it in the mountains of Andalusia or on the coast of distant Easter Island? Why does the conversation sometimes suddenly stop? Last week I visited the Beeline company and tried to figure out how cellular communications work...

A large area of ​​the populated part of our country is covered by Base Stations (BS). In the field they look like red and white towers, and in the city they are hidden on the roofs of non-residential buildings. Each station picks up signals from mobile phones at a distance of up to 35 kilometers and communicates with the mobile phone via service or voice channels.

After you have dialed a friend's number, your phone contacts the Base Station (BS) closest to you via a service channel and asks to allocate a voice channel. The Base Station sends a request to the controller (BSC), which forwards it to the switch (MSC). If your friend is a subscriber to the same cellular network, then the switch will check the Home Location Register (HLR), find out where the called subscriber is currently located (at home, in Turkey or Alaska), and transfer the call to the appropriate switch from where it was sent will be sent to the controller and then to the Base Station. The Base Station will contact your mobile phone and connect you to your friend. If your friend is on a different network or you are calling a landline, your switch will contact the corresponding switch on the other network. Difficult? Let's take a closer look. The Base Station is a pair of iron cabinets locked in a well-conditioned room. Considering that it was +40 outside in Moscow, I wanted to live in this room for a while. Typically, the Base Station is located either in the attic of a building or in a container on the roof:

2.

The Base Station antenna is divided into several sectors, each of which “shines” in its own direction. The vertical antenna communicates with phones, the round antenna connects the Base Station to the controller:

3.

Each sector can handle up to 72 calls simultaneously, depending on setup and configuration. A Base Station can consist of 6 sectors, so one Base Station can handle up to 432 calls, however, a station usually has fewer transmitters and sectors installed. Cellular operators prefer to install more BS to improve the quality of communication. The Base Station can operate in three bands: 900 MHz - the signal at this frequency travels further and penetrates better inside buildings 1800 MHz - the signal travels over shorter distances, but allows you to install a larger number of transmitters in 1 sector 2100 MHz - 3G Network This is what the cabinet looks like with 3G equipment:

4.

900 MHz transmitters are installed at Base Stations in fields and villages, and in the city, where Base Stations are stuck like hedgehog needles, communication is mainly carried out at a frequency of 1800 MHz, although any Base Station may have transmitters of all three ranges simultaneously.

5.

6.

A signal with a frequency of 900 MHz can reach up to 35 kilometers, although the “range” of some Base Stations located along highways can reach up to 70 kilometers, due to the reduction in the number of simultaneously served subscribers at the station by half. Accordingly, our phone with its small built-in antenna can also transmit a signal over a distance of up to 70 kilometers... All Base Stations are designed to provide optimal radio coverage at ground level. Therefore, despite a range of 35 kilometers, a radio signal is simply not sent to the aircraft’s flight altitude. However, some airlines have already begun installing low-power base stations on their aircraft that provide coverage within the aircraft. Such a BS is connected to a terrestrial cellular network using satellite channel. The system is complemented by a control panel that allows the crew to turn the system on and off, as well as certain types of services, for example, turning off the voice on night flights. The phone can measure the signal strength from 32 Base Stations simultaneously. It sends information about the 6 best (in terms of signal strength) via the service channel, and the controller (BSC) decides which BS to transfer the current call (Handover) if you are on the move. Sometimes the phone may make a mistake and transfer you to a BS with a worse signal, in which case the conversation may be interrupted. It may also turn out that at the Base Station that your phone has selected, all voice lines are busy. In this case, the conversation will also be interrupted. They also told me about the so-called “upper floor problem.” If you live in a penthouse, then sometimes, when moving from one room to another, the conversation may be interrupted. This happens because in one room the phone can “see” one BS, and in the second - another, if it faces the other side of the house, and, at the same time, these 2 Base Stations are located at a great distance from each other and are not registered as “ neighboring" mobile operator. In this case, the call will not be transferred from one BS to another:

Communication in the metro is provided in the same way as on the street: Base Station - controller - switch, with the only difference being that small Base Stations are used there, and in the tunnel, coverage is provided not by an ordinary antenna, but by a special radiating cable. As I wrote above, one BS can make up to 432 calls simultaneously. Usually this power is enough, but, for example, during some holidays the BS may not be able to cope with the number of people wanting to call. This usually happens on New Year's Day, when everyone starts congratulating each other. SMS are transmitted via service channels. On March 8 and February 23, people prefer to congratulate each other via SMS, sending funny poems, and phones often cannot agree with the BS on the allocation of a voice channel. I was told an interesting case. In one area of ​​Moscow, subscribers began to receive complaints that they could not get through to anyone. Technical specialists began to figure it out. Most voice channels were free, but all service channels were busy. It turned out that next to this BS there was an institute where exams were going on and students were constantly exchanging text messages. The phone divides long SMS into several short ones and sends each one separately. Technical service staff advise sending such congratulations via MMS. It will be faster and cheaper. From the Base Station the call goes to the controller. It looks as boring as the BS itself - it’s just a set of cabinets:

7.

Depending on the equipment, the controller can serve up to 60 Base Stations. Communication between the BS and the controller (BSC) can be carried out via a radio relay channel or via optics. The controller controls the operation of radio channels, incl. controls the subscriber’s movement and signal transmission from one BS to another. The switch looks much more interesting:

8.

9.

Each switch serves from 2 to 30 controllers. It occupies a large hall, filled with various cabinets with equipment:

10.

11.

12.

The switch controls traffic. Remember the old movies where people first dialed the “girl”, and then she connected them to another subscriber by switching the wires? Modern switches do the same thing:

13.

To control the network, Beeline has several cars, which they affectionately call “hedgehogs.” They move around the city and measure the signal level of their own network, as well as the level of the network of their colleagues from the Big Three:

14.

The entire roof of such a car is covered with antennas:

15.

Inside there is equipment that makes hundreds of calls and takes information:

16.

24-hour monitoring of switches and controllers is carried out from the Mission Control Center of the Network Control Center (NCC):

17.

There are 3 main areas for monitoring the cellular network: accident rates, statistics and feedback from subscribers. Just like in airplanes, all cellular network equipment has sensors that send a signal to the central control system and output information to dispatchers’ computers. If some equipment fails, the light on the monitor will begin to “blink.” The CCS also tracks statistics for all switches and controllers. He analyzes it, comparing it with previous periods (hour, day, week, etc.). If the statistics of any of the nodes began to differ sharply from previous indicators, then the light on the monitor will again begin to “blink”. Feedback accepted by subscriber service operators. If they cannot resolve the problem, the call is transferred to a technician. If he turns out to be powerless, then an “incident” is created in the company, which is resolved by the engineers involved in the operation of the relevant equipment. The switches are monitored 24/7 by 2 engineers:

18.

The graph shows the activity of Moscow switches. It is clearly visible that almost no one calls at night:

19.

Control over the controllers (forgive the tautology) is carried out from the second floor of the Network Control Center:

22.

21.

Communication is called mobile if the source of information or its recipient (or both) move in space. Radio communication has been mobile since its inception. Above, in the third chapter, it is shown that the first radio stations were intended for communication with moving objects—ships. After all, one of the first radio communication devices A.S. Popov was installed on the battleship Admiral Apraksin. And it was thanks to radio communication with him that in the winter of 1899–1900 it was possible to save this ship, lost in the ice of the Baltic Sea. However, in those years, this “mobile communication” required bulky radio transceiver devices, which did not contribute to the development of much-needed individual radio communications even in the Armed Forces, not to mention private clients.

On June 17, 1946, in St. Louis, USA, telephone business leader AT&T and Southwestern Bell launched the first radiotelephone network for private customers. The elemental base of the equipment was lamp electronic devices, so the equipment was very bulky and was intended only for installation in cars. The weight of the equipment without power sources was 40 kg. Despite this, the popularity of mobile communications began to grow rapidly. This created a new problem, more serious than weight and size indicators. An increase in the number of radios, with a limited frequency resource, led to strong mutual interference for radio stations operating on channels close in frequency, which significantly deteriorated the quality of communication. To eliminate mutual interference at repeating frequencies, it was necessary to ensure a minimum one-hundred-kilometer separation in space between two groups of radio systems. That is why mobile communications were mainly used for the needs of special services. For mass implementation, it was necessary to change not only the weight and size indicators, but also the very principle of organizing communication.

As noted above, in 1947 a transistor was invented that performs the functions of vacuum tubes, but has a significantly smaller size. It was the advent of transistors that was of great importance for the further development of radiotelephone communications. The replacement of vacuum tubes with transistors created the preconditions for widespread adoption mobile phone. The main limiting factor was the principle of communication organization, which would eliminate or at least reduce the influence of mutual interference.

Studies of the ultrashort wave range, carried out in the 40s of the last century, revealed its main advantage over short waves - wide range, i.e. large frequency capacity and the main disadvantage - strong absorption of radio waves by the propagation medium. Radio waves in this range are not capable of bending around the earth's surface, so the communication range was provided only on the line of sight, and depending on the power of the transmitter, a maximum of 40 km was provided. This disadvantage soon turned into an advantage, which gave impetus to the active mass introduction of cellular telephone communications.

In 1947, an employee of the American company Bell Laboratories D. Ring proposed a new idea for organizing communications. It consisted of dividing space (territory) into small areas - cells (or cells) with a radius of 1–5 kilometers and separating radio communications within one cell (by rationally repeating the communication frequencies used) from communications between cells. Frequency repetition has significantly reduced the problems of using frequency resources. This made it possible to use the same frequencies in different cells distributed in space. In the center of each cell it was proposed to locate a basic receiving and transmitting radio station, which would provide radio communication within the cell with all subscribers. The cell size was determined by the maximum communication range of the radiotelephone device with the base station. This maximum range is called the cell radius. During a conversation, the cellular radiotelephone is connected to the base station by a radio channel through which the telephone conversation is transmitted. Each subscriber must have his own microradio station - a “mobile phone” - a combination of a telephone, a transceiver and a mini-computer. Subscribers communicate with each other through base stations, which are connected to each other and to the public telephone network.

To ensure uninterrupted communication when a subscriber moves from one zone to another, it was necessary to use computer control over the telephone signal emitted by the subscriber. It was computer control that made it possible to switch a mobile phone from one intermediate transmitter to another within just a thousandth of a second. Everything happens so quickly that the subscriber simply does not notice it. Thus, the central part of the mobile communication system is computers. They find a subscriber located in any of the cells and connect him to the telephone network. When a subscriber moves from one cell (cell) to another, computers seem to transfer the subscriber from one base station to another and connect the subscriber of a “foreign” cellular network to “their” network. This happens at the moment when the “foreign” subscriber finds itself in the coverage area of ​​the new base station. Thus, roaming is carried out (which in English means “wandering” or “wandering”).

As noted above, the principles of modern mobile communications were an achievement already at the end of the 40s. However, in those days, computer technology was still at such a level that its commercial use in telephone communication systems was difficult. Therefore, the practical use of cellular communications became possible only after the invention of microprocessors and integrated semiconductor chips.

The first cellular telephone, a prototype of a modern device, was designed by Martin Cooper (Motorola, USA).

In 1973, in New York, on top of a 50-story building, Motorola installed the world's first cellular communications base station under his leadership. It could serve no more than 30 subscribers and connect them to landline lines.

On April 3, 1973, Martin Cooper dialed his boss and said the following words: “Imagine, Joel, that I am calling you from the world's first cell phone. I have it in my hands, and I’m walking down a New York street.”

The phone Martin called from was called Dyna-Tac. Its dimensions were 225x125x375 mm, and its weight was no less than 1.15 kg, which, however, is much less than the 30 kilogram devices of the late forties. Using the device, it was possible to make calls and receive signals, and negotiate with the subscriber. This telephone had 12 keys, of which 10 were digital for dialing the subscriber's number, and the other two ensured the start of a conversation and interrupted the call. Dyna-Tac batteries allowed talk time for about half an hour, and required 10 hours to charge.

Although much of the development took place in the United States, the first commercial cellular network was launched in May 1978 in Bahrain. Two cells with 20 channels in the 400 MHz band served 250 subscribers.

A little later, cellular communications began their triumphal march throughout the world. More and more countries realized the benefits and convenience it could bring. However, the lack of a unified international standard for the use of the frequency range eventually led to the fact that the owner of a cell phone, moving from one state to another, could not use the mobile phone.

In order to eliminate this main shortcoming, since the late seventies, Sweden, Finland, Iceland, Denmark and Norway began joint research to develop a single standard. The result of the research was the communication standard NMT-450 (Nordic Mobile Telephone), which was intended to operate in the 450 MHz range. This standard first began to be used in 1981 in Saudi Arabia, and only a month later in Europe. Various variants of the NMT-450 have been adopted in Austria, Switzerland, Holland, Belgium, Southeast Asia and the Middle East.

In 1983, the AMPS (Advanced) standard network was launched in Chicago. Mobile Phone Service), which was developed by Bell Laboratories. In 1985, in England, the TACS (Total Access Communications System) standard was adopted, which was a variation of the American AMPS. Two years later, due to the sharply increased number of subscribers, the HTACS (Enhanced TACS) standard was adopted, adding new frequencies and partially correcting the shortcomings of its predecessor. France stood apart from everyone else and began using its own Radiocom-2000 standard in 1985.

The next standard was NMT-900, using frequencies of the 900 MHz range. A new version came into use in 1986. It allowed to increase the number of subscribers and improve the stability of the system.

However, all of these standards are analog and belong to the first generation of cellular communication systems. They use an analog method of transmitting information using frequency (FM) or phase (FM) modulation - as in conventional radio stations. This method has a number of significant disadvantages, the main ones being the ability to listen to conversations of other subscribers and the inability to combat signal fading when the subscriber moves, as well as under the influence of the terrain and buildings. Overloaded frequency bands caused interference during conversations. Therefore, by the end of the 1980s, the creation of the second generation of cellular communication systems began, based on digital signal processing methods.

Previously, in 1982, the European Conference of Postal and Telecommunications Administrations (CEPT), uniting 26 countries, decided to create a special group Groupe Special Mobile. Its goal was to develop a single European standard for digital cellular communications. The new communication standard was developed over the course of eight years, and was first announced only in 1990 - then the standard specifications were proposed. The special group initially decided to use the 900 MHz band as a single standard, and then, taking into account the prospects for the development of cellular communications in Europe and throughout the world, it was decided to allocate the 1800 MHz band for the new standard.

The new standard is called GSM - Global System for Mobile Communications. GSM 1800 MHz is also called DCS-1800 (Digital Cellular System 1800). The GSM standard is a digital cellular communication standard. It implements time division of channels (TDMA - time division multiple access, message encryption, block coding, as well as GMSK modulation) (Gaussian Minimum Shift Keying).

The first country to launch the GSM network is Finland, which launched this standard into commercial operation in 1992. The following year, the first DCS-1800 One-2-One network went live in the UK. From now on, global distribution begins GSM standard Worldwide.

The next step after GSM is the CDMA standard, which provides faster and more reliable communications through the use of code division channels. This standard began to emerge in the United States in 1990. In 1993, CDMA (or IS-95) began to be used in the United States in the 800 MHz frequency range. At the same time, the DCS-1800 One-2-One network began operating in England.

In general, there were many communication standards, and by the mid-nineties, most civilized countries were smoothly switching to digital specifications. If the first generation networks allowed the transmission of only voice, then the second generation of cellular communication systems, which is GSM, allows the provision of other non-voice services. In addition to the SMS service, the first GSM phones made it possible to transmit other non-voice data. For this purpose, a data transfer protocol was developed, called CSD (Circuit Switched Data - data transfer over switched lines). However, this standard had very modest characteristics - the maximum data transfer rate was only 9600 bits per second, and then only under the condition of stable communication. However, such speeds were quite enough for transmitting a fax message.

The rapid development of the Internet in the late 90s led to the fact that many cellular users wanted to use their handsets as modems, and the existing speeds were clearly not enough for this.
In order to somehow satisfy the needs of their customers for access to the Internet, engineers invent the WAP protocol. WAP is an abbreviation for Wireless Application Protocol, which translates to Wireless Application Protocol. In principle, WAP can be called a simplified version of the standard Internet protocol HTTP, only adapted to the limited resources of mobile phones, such as small display sizes, low performance of telephone processors and low data transfer rates in mobile networks. However, this protocol did not allow viewing standard Internet pages; they had to be written in WML, which was adapted for cell phones. As a result, although subscribers of cellular networks received access to the Internet, it turned out to be very “stripped down” and uninteresting. Plus, to access WAP sites, the same communication channel was used as for voice transmission, that is, while you are loading or viewing a page, the communication channel is busy, and the same money is debited from your personal account as during the conversation. As a result, a rather interesting technology was practically buried for some time and was used very rarely by subscribers of cellular networks of various operators.
Cellular equipment manufacturers urgently had to look for ways to increase data transfer speeds, and as a result, HSCSD (High-Speed ​​Circuit Switched Data) technology was born, which provided quite acceptable speeds of up to 43 kilobits per second. This technology was popular among a certain circle of users. But still, this technology did not lose the main drawback of its predecessor - the data was still transmitted over the voice channel. The developers again had to engage in painstaking research. The efforts of the engineers were not in vain, and quite recently a technology came into being called GPRS (General Packed Radio Services) - this name can be translated as a packet radio data transmission system. This technology uses the principle of channel separation for voice and data transmission. As a result, the subscriber does not pay for the duration of the connection, but only for the amount of data transmitted and received. In addition, GPRS has another advantage over earlier mobile data technologies - during a GPRS connection, the phone is still able to receive calls and SMS messages. At the moment, modern phone models on the market pause the GPRS connection when making a conversation, which automatically resumes when the conversation ends. Such devices are classified as class B GPRS terminals. It is planned to produce class A terminals that will allow you to simultaneously download data and conduct a conversation with the interlocutor. There are also special devices, which are intended only for data transmission, and they are called GPRS modems or class C terminals. Theoretically, GPRS is capable of transmitting data at a speed of 115 kilobits per second, but at the moment most telecom operators provide a communication channel that allows speeds of up to 48 kilobits per second give me a sec. This is primarily due to the equipment of the operators themselves and, as a consequence, the lack of cell phones on the market that support higher speeds.

With the advent of GPRS, the WAP protocol was again remembered, since now, through the new technology, access to small-volume WAP pages becomes many times cheaper than in the days of CSD and HSCSD. Moreover, many telecom operators provide unlimited access to WAP network resources for a small monthly subscription fee.
With the advent of GPRS, cellular networks ceased to be called second generation networks - 2G. We are currently in the 2.5G era. Non-voice services are becoming increasingly popular as the cell phone, computer and Internet are merging. Developers and operators are offering us more and more different additional services.
Thus, using the capabilities of GPRS, a new message transmission format was created, which was called MMS (Multimedia Messaging Service), which, unlike SMS, allows you to send not only text, but also various multimedia information from a cell phone, for example, sound recordings, photographs and even video clips. Moreover, an MMS message can be transferred either to another phone that supports this format or to an email account.
The increasing power of phone processors now allows you to download and run various programs on it. The Java2ME language is most often used to write them. Owners of most modern phones can now easily connect to the website of Java2ME application developers and download to their phone, for example, new game or other necessary program. Also, no one will be surprised by the ability to connect the phone to personal computer, in order to, using a special software, most often supplied with the handset, save or edit an address book or organizer on a PC; while on the road, using a mobile phone + laptop combination, access the full Internet and view your email. However, our needs are constantly growing, the volume of transmitted information is growing almost daily. And more and more demands are being placed on cell phones, as a result of which the resources of current technologies are becoming insufficient to satisfy our increasing demands.

It is precisely to solve these requests that the fairly recently created third generation 3G networks are designed, in which data transmission dominates over voice services. 3G is not a communication standard, but a general name for all high-speed cellular networks that will grow and are already growing beyond the existing ones. Huge data transfer rates allow you to transfer high-quality video images directly to your phone and maintain a constant connection to the Internet and local networks. The use of new, improved security systems makes it possible today to use a telephone for various financial transactions - a mobile phone is quite capable of replacing a credit card.

It is quite natural that third generation networks will not become the final stage in the development of cellular communications - as they say, progress is inexorable. The ongoing integration of various types of communications (cellular, satellite, television, etc.), the emergence of hybrid devices that include a cell phone, PDA, and video camera will certainly lead to the emergence of 4G and 5G networks. And even science fiction writers today are unlikely to be able to tell how this evolutionary development will end.

Globally, there are currently about 2 billion mobile phones in use, of which more than two-thirds are connected to the GSM standard. The second most popular is CDMA, while the rest represent specific standards used mainly in Asia. Now in developed countries there is a situation of “saturation”, when demand stops growing.

The service allows you to hide the identification of your mobile phone number when calling the numbers of other subscribers. The service works correctly when the calling and called subscribers are located in the Moscow region. The operation of the service is not guaranteed for outgoing calls to phones of subscribers of networks other than Rostelecom, including public city networks.

Automatic Caller ID (ANI) allows you to find out the name or number from which incoming call, find out the numbers of the latest incoming calls - received or missed, set different ringtones for the numbers. The service is connected to all subscribers free of charge.

Short Message Service - short message transmission service. The service provides the transmission and reception of short text messages via a digital cellular network.

Additional parameters that are not listed should be left at their default values. After manual settings phone, send an MMS to any recipient, for example, to your own number. This is necessary to register your number in the Rostelecom network as a user of the MMS service.

Basic settings mobile internet. To configure your phone to access the Internet or to work from a computer using the phone as a modem, you need to set the following parameters:

The service provides the opportunity to communicate with several interlocutors at the same time, which is convenient for conducting business negotiations when it is impossible to quickly gather all those responsible and interested in the discussion for a personal meeting. If you need to communicate with several friends at the same time. Up to 6 subscribers can participate in the conference simultaneously, including the call initiator.

The conference initiator has the ability to connect both fixed and fixed line subscribers to the conversation. mobile networks; switch the current conference to standby mode (in this case, participants will continue telephone communication). Make outgoing calls, answer incoming calls, join or remove participants from a conversation. These actions can be performed through the phone menu. Conference calling of incoming calls is available when the Call Waiting service is active.

Conference participants have the ability to make outgoing and receive incoming calls without interrupting the conference, leave the conference without interrupting the communication of other participants (if the initiator leaves, the remaining participants will be automatically disconnected).

You won't miss a single call. The service will report all missed calls during the time when the phone was out of network coverage or turned off.

The service is provided to Rostelecom subscribers when they are in the Moscow region and in roaming.

If the balance is close to zero and there is no way to top up your account, you can use the “Promised Payment” service to make a temporary payment and continue communication.

Receipt of the Promised Payment is possible immediately after the previously credited payment has been written off.

The service allows you not to miss an important call, even if it comes during a conversation with another interlocutor. A special sound signal will notify you of a new call. Following the phone prompts, you can choose who to talk to first, or communicate alternately with both interlocutors.

The service is included in the tariff.

"Social networks" is unlimited internet traffic to the most popular social networks “Facebook”, “VKontakte”, “Odnoklassniki”. Option included in subscription fee all new tariff plans valid from September 20, 2017, except for the “For Unlimited” tariff plan, the “Endless Story” tariff plan, and cannot be disabled.

“Messengers” - unlimited Internet traffic, the most popular instant messengers “WhatsApp”, “Viber”, “TamTam”. The option is included in the subscription fee of new tariff plans“SUPER SIM S”, “SUPER SIM M”, “SUPER SIM L”, “SUPER SIM XL” (from 09/20/17) and cannot be disabled.

The option is valid when you are in your home region and when traveling around Russia with the exception of the Republic of Crimea and the city of Sevastopol. If pages, links or videos are opened through the sites or applications “Facebook”, “VKontakte”, “Odnoklassniki”, the display of which requires a connection to other sites, Internet traffic is paid by the subscriber in accordance with the current tariff plan and options.

Can be connected to archived TPs via USSD command.

"Navigation" - unlimited Internet traffic when using the applications "Yandex.Maps", "Yandex.Navigator" and "Yandex.Transport". The option is valid when you are in your home region and when traveling around Russia with the exception of the Republic of Crimea and the city of Sevastopol. If pages, links or videos are opened through the sites or applications “Facebook”, “VKontakte”, “Odnoklassniki”, the display of which requires a connection to other sites, Internet traffic is paid by the subscriber in accordance with the current tariff plan and options.

It can be connected both to archived tariff plans and to new tariff plans, except for the “For Unlimited” tariff plan, the “Endless Story” tariff plan, via the USSD command.

Absolute forwarding (ALL CALLS) ensures that all incoming calls are transferred to a specified phone number.

Forwarding, when the phone is busy (IF BUSY), transfers incoming calls to a specified phone number when the subscriber's phone is busy.

Forwarding if the subscriber is unavailable (WHEN UNREACHABLE) ensures that incoming calls are transferred to a specified telephone number if the subscriber is out of the service area or has turned off his device.

Forwarding, if there is no answer (IF NO REPLY), transfers incoming calls to a specified telephone number if the subscriber pressed the end call button or did not answer the call within the time interval set by him: 5, 10, 15, 20, 25 or 30 seconds ( By default, the system sets the interval to 30 seconds).

Cancel all redirects.

The additional service “Exchange Minutes” is an opportunity to exchange your minutes for Internet traffic. The service is provided free of charge on tariff plans open for connection, subject to the charging of the subscription fee established for the subscriber’s chosen tariff.

Exchange rate:
1 minute = 10.24 MB
10 minutes = 102.4 MB
100 minutes = 1 GB

Peculiarities:
- You can exchange minutes both from the main package included in the tariff, and those received as part of the transfer of package balances from the previous month.
- You can exchange any number of minutes at any time after the main package is assigned, but no more than 10 times a month.
- Minutes cannot be exchanged while the “Add traffic”/ “500MB+”/ “1GB+” options are in effect
- Exchanged GB are included in the main package. First of all, Internet traffic from the transferred package is consumed, after it is exhausted - from the main Internet traffic package.
- Exchanged GB are transferred to the next billing period in an amount no more than the volume of two packages at the main tariff.
- When changing tariff plan unused Internet traffic is burned.
- Exchange of minutes is available in roaming, including the ability to use exchange traffic while roaming.
- The service can be used throughout Russia, with the exception of the Republic of Crimea and the city of Sevastopol.

The service is provided when you are in your home region. The subscription fee is charged only on the days when SMS is sent. The subscription fee includes 100 SMS messages in a day. The service is not compatible with other SMS discounts.

CONNECTION	DISCONNECT	CHECKING STATUS	CONNECTION COST	SUBSCRIPTION FEE
*100*334*1# call	*100*334*0# call	*100*334*2# call	0 / 20 rub.	15 rub./day

Discount on international calls to certain directions - a single set of directions and cost in all regions.

Management and cost of service

Cost of a call with the option connected

Direction	Price
Uzbekistan, Europe and the Baltics, Vietnam, Thailand, Japan, Israel, Brazil, Argentina, Colombia	5 rub./min.
Kazakhstan (except prefix 876)	6 rub./min.
Tajikistan, Ukraine, Kyrgyzstan, Turkmenistan, Türkiye	9 rub./min.
Armenia, Georgia, Abkhazia, Azerbaijan, Moldova, Estonia	15 rub./min.
Belarus	25 rub./min.
Montenegro, Bosnia and Herzegovina, Serbia, Switzerland, Slovenia, Albania, Macedonia, Monaco, Andorra, Liechtenstein, San Marino, Vatican	Basic cost
China, USA and Canada	0.80 RUR/min
South Korea, India, Mongolia	1.5 rub./min.

Additional packages of Minutes and SMS are activated on the following package tariff plans: “Super SIM” line (M, L, XL), “For All” line (L, XL, 2XL).

Price

Tariff plan		First/subsequent connections	Subscription fee
TP "Supersimka M", TP "New history. Everywhere", TP "New history. In conversation"	100 minutes of outgoing calls to numbers of operators in your home region
TP "Supersimka L", TP "Supersimka XL", TP "On all L", TP "On all XL", TP "Whole history", TP "Family history"	100 minutes of outgoing calls to Russian operator numbers
TP "For the Internet everywhere", TP "For impressions everywhere"	50 minutes of outgoing calls to numbers of operators in your home region
TP "For Unlimited", TP "For Family", "TP "Endless Story"	50 minutes of outgoing calls to Russian operator numbers
All tariffs	100 SMS to home region

The package of minutes is not connected to the SuperSimka Free tariff plan, the SuperSimka S tariff plan, and the New History tariff plan. Online".
The SMS package is not connected to the SuperSimka Free and SuperSimka S tariff plans.

Control

X-number of simultaneously connected packages
The choice of available package of minutes will be determined by the tariff plan itself.

Features of use

If there are not enough funds on your personal account balance to pay for all packages in full, only the subscription fee for the tariff will be charged, and all additional packages will be disabled. To use packages in the next billing period, they must be activated.

The maximum number of connections of the available package of minutes per month is 5.

The maximum number of SMS package connections per month is 5.

The number of simultaneously connected packages of one type of service is not limited, but no more than 5.

The total available number of simultaneously connected packages is 10 (5 minute packages + 5 SMS packages).

Connection is possible even if the main package is not used up.

Not available for participants of the “Year Without Worries” campaign.

The "Exchange Minutes" option is available.

When the service is disconnected, the unused volume remains and can be used until the end of the subscriber's billing period.

Unused packages are carried over to the next month.

Additional packages of minutes are available for use only when you are in the connection region.

The SMS Package includes messages to subscriber numbers of all Russian telecom operators.

Select a package of the required volume, and if necessary, add the required number of SMS within the current month:

Connection cost:

Control:

	Team uniform	Connection	Shutdown	Checking status
Package 100 SMS
		390*1 to number 100	390*0 to number 100	390*2 to number 100
Package Plus 100 SMS
		392*1 to number 100	392*0 to number 100	392*2 to number 100
Package 300 SMS
		391*1 to number 100	391*0 to number 100	391*2 to number 100
Package Plus 300 SMS
		393*1 to number 100	393*0 to number 100	393*2 to number 100

The subscription fee for services is charged in full at the time access to the service is provided and then monthly as long as the service is active for the Subscriber.

If there are insufficient funds for the next debit of the subscription fee, the provision of the service is suspended. When you top up your account, the service is automatically resumed.

In case of deactivation of the “Package 100 SMS” or “Package 300 SMS” services before it is exhausted, the SMS provided under the Package can be used until the end of the billing period/month.

The volume of SMS provided under the Package that is not used in the current billing period is transferred to the next period, subject to timely payment of the subscription fee.

Outgoing SMS to short numbers, as well as to the numbers of content providers are not included in the Package and are charged in accordance with the terms of the subscriber’s connected tariff plan.

The service is incompatible with other discounts on SMS, except for the packages included in the subscription fee for the “Plus 100 SMS” and “Plus 300 SMS” tariff and services.

When connecting SMS packages to packaged TPs with included SMS volumes, spent on numbers of any operators in the home region, when sending SMS to numbers in the home region, the SMS package included in the TP is consumed first, after it is exhausted, SMS are consumed from the packages provided within the " 100 SMS", "300 SMS".

Features of using the services “Package 100 SMS” or “Package 300 SMS”:

You can additionally activate the “Plus 100 SMS” or “Plus 300 SMS” service. The packages are activated independently by the subscriber when the “100 SMS” or “300 SMS” Packages are exhausted and are valid until the volume of messages is exhausted or until the end of the current period in which they were connected.

The number of connections per month is unlimited.

Available for use only when located in the connection region.