All cellular operators (MTS, Beeline, Megafon) broadcast at frequencies of 900MHz and 1800MHz.
Depending on the area, they can broadcast:
- at 900MHz
- at 1800MHz
- at 900MHz and 1800MHz simultaneously
As a rule, the network frequency looks like this:
- MTS, Beeline in the city - 900 MHz
- Megaphone in the city - 1800 MHz
- MTS, Beeline, Megafon in the region - 900 MHz
But there are exceptions when operators broadcast on other frequencies.
One GSM channel serves 7 simultaneously talking subscribers. The 1800th range prevails mainly for densely populated areas, i.e. cities, because can serve more subscribers. And the 900th range is used everywhere. The principal advantage of the 900 range is the range of up to 35 km. in line of sight, while at 1800 frequency - only 8 km.
Another important indicator is the level of signals measured in dBm (English dBm). These values are negative, i.e. -60 dBm is greater than -65 dBm.
The GSM signal level can be measured with a spectrum analyzer, or with the NetMonitor program.
1. Call the mobile operator MTS, Beeline, Megafon and clarify at what frequency your cell is broadcasting.
Please provide your address.
Cellular operators, as a rule, do not answer immediately. It sometimes takes several days to receive information.
2. On some phones (especially old ones) there is an option to determine the frequency on which he contacted the base station.
3. Install the program on your smartphone NetMonitor.
The program will show the location of the nearest towers, their number, signal level. On the Internet, by the number of the tower, you can find information about it.
4. You can determine the signal level and its frequency with a spectrum analyzer.
5. Call our specialist to determine the signal on the spot.
The measurement is made by a spectrum analyzer.
Call our tech. Department.
Before you start looking for GSM repeaters and choosing an installation company, answer yourself the key question: What communication standard do I need to strengthen: only GSM-900 ( Voice connection), only GSM-1800 (voice), GSM-900 + GSM-1800 (voice) and/or 3G (Internet)?
The thing is that the speech signal operates at frequencies of 900 MHz and 1800 MHz. And 3G-Internet - only at a frequency of 2400 MHz.
If you need to amplify only the speech radio signal, then you can go outside (outside the amplified room) and measure the signal level (the number of "sticks" on the phone display). If there are "two or three sticks", then thanks to the system of repeaters and antennas you will receive a stable cellular signal.
| Repeater | Frequency | Gain | Square |
| Vector R-400 | 900 MHz | 50 dBi | 30-100 sq.m. |
| Vector R-610 | 900 MHz | 60 dBi | 100-300 sq.m. |
| Vector R-710 | 900 MHz | 70 dBi | 200 - 600 sq.m. |
| Vector R-810 | 900 MHz | 80 dBi | 500 - 1600 sq.m. |
| Vector R-600D | 1800 MHz | 65 dBi | 200 - 600 sq.m. |
| Vector R-600W | 900 / 1800 MHz | 65 dBi | 200 - 600 sq.m. |
If you need only one operator, for example, MTS. Then try to capture several channels. For example, it is better to catch 2-3 channels with a signal level of -60 than 1 channel -50, and the rest -70. If you need to provide a signal to all mobile operators, then try to put external antenna so that the signal to the input of the repeater comes approximately the same from all cellular operators, otherwise the range from the internal antennas will be proportional to the incoming signals. For example, the signals of MTS "-70", Beeline "-60", Megafon "-50" get to the input of the repeater, then at the output of the internal antennas we will observe the following situation, as shown below: 
The NetMonitor program will help you accurately orient the direction of the external directional antenna, it will not only show the level GSM signal, but also the location of the nearest base station.
Sincerely, CJSC "Radiovnimanie".
(Information provided with the consent of the partner - http://www.exclusive-comfort.ru/uchebnik-gsm-repiter.shtml)
Determining the frequency using Android applications
I Introduction
The carrier frequency (or frequency range) of a 3G/4G signal is one of the most important parameters when choosing an antenna. In the end, you may not know the location of the base stations in the vicinity - simply by rotating the antenna, you can determine this direction by the signal level. If you do not know the frequency, then the signal can not be caught at all.
Since the definition of frequency for 3G, 4G and 4G-Advanced (4G+) standards are different, we will consider methods for determining frequencies separately.
II. Determining the frequency of a 3G signal
As you know, two frequency bands for 3G are adopted in Russia, these are 2100 MHz and 900 MHz. The frequency of 900 MHz is adopted in those regions where, for military reasons, it is unacceptable to use 2100 MHz. For example, the South-East of the Moscow region.
Every smartphone has a hidden program called Netmonitor. For each phone model, this program is activated by its individual code. For Android smartphones from Samsung, you need to enter the code * # 0011 # in the dialing mode. For other Android phones, the codes are: *#*#4636#*#* or *#*#197328640#*#* depending on the version. Most full list"secret" codes to activate this hidden program For different models phones, including the iPhone, can be found.
So, in 3G mode, I dial the code *#0011# on my Samsung dialer and get:
Here RX = 10713 is the channel number by which the carrier frequency is determined.
If the channel value is in the range 2937-3088, then it is 3G/UMTS900.
If the channel value is in the range 10562-10838, then it is 3G/UMTS2100.
RI \u003d -64 dB is the signal level from the base station of the cellular operator (RSSI).
There are no special Android applications for determining the frequency of a 3G signal in the Play Market.
III. Determining the frequency of a 4G signal
In 4G LTE mode, cellular operators can operate in three bands - 800 MHz, 1800 MHz and 2600 MHz. To determine the frequency in this mode, you can also use the smartphone's built-in Netmonitor. How to do this is described in detail in.
There are only a few applications¹ that are claimed by the developers to determine the frequency, among other functions. However, everything is not so simple. Some applications (G-NetTrack, Net Monitor, etc.) require operating system not lower than Android 7.X. Others (LTE Discovery) require the smartphone to be in Root² mode.
However, there was an application that gives out the frequency of the 4G signal. Meet CellMapper . To use the application, you need to register on the site, registration is free.
In order for the program to display the value of the carrier frequency on the screen, in the settings you need to check the box “Calculate GSM / UMTS / LTE frequencies”. In my smartphone (Samsung GT-i9505, Android 5.01), frequencies for GSM and UMTS are not issued, for the LTE standard we get what is shown in the screenshot:
The program gives a lot of information about the connected tower and neighbors, including the signal frequency in the form of Band 7. This is the frequency of 2600 MHz. Other possible frequency ranges can be identified.
I will not describe each tab of the program, there are (on English language) and FAQ, I will only note that this application gives the frequency only for standard 4 signalsG. To determine the frequency in the 3G standard, as I said above, no android applications were found.
IV. The situation with 4G+
V. Conclusion
A few notes at the end of the article.
It would be desirable that all tasks for choosing an antenna could be performed on a pocket device such as a smartphone. However, the most reliable and cheapest way to determine the carrier frequency (or frequencies) of an Internet signal is a computer (laptop) with a modem that has a HiLink interface or an MDMA program.
The rapid development of the 4G+ standard poses difficult challenges for antenna developers as well. How to combine different frequencies in one antenna with good gain (about 17-20 dBi), for example, 800 + 2600 MHz? Moreover, so that there was MIMO. If this problem is not solved, then you will have to come up with complex designs from antennas of different ranges, combine their signals with diplexers, in general, the problem is not simple and cheap. Or stay on 4G and be content with speeds that, in theory, can be increased at times.
I look forward to feedback and comments, your dmitryvv.
1] Only free apps are considered.
2] For those who want to experiment with their smartphone, at the risk of turning it into a brick, I send it here and here (update to Android 7.XX), or on the w3bsit3-dns.com forum
3] I must say that even the best foreign samples of this class (for example, the Australian company Telstra, costing about $300) do not exceed 8...11 dBi in amplification.
After doing a little research, we realized that there is very little information on the Internet on the situation with mobile communications in Russia, which is why we decided to collect and present this information in a structured way for our readers. We at jammer hope that this article can be useful even for advanced users of mobile communications, because the situation with it in the Russian Federation is rather confusing, it is difficult to say in what frequencies and on what standard this or that operator works, how this or that service is provided. You have probably come across such an abbreviation as 3G, or 4G - this is how different generations of communication are called, which operate at different frequencies, have different forms of signal modulation, they differ from each other in data transfer speed. We will break communication standards by generation and start the most common in the Russian Federation, 2G.
A brief overview of the main communication standards can be found in the "Articles" section of the jammer.su website, or simply by clicking on this link.
The second generation of mobile communications is most common in Russia. It ranks first not only in terms of coverage area, but also in terms of the number of subscribers. The second generation operates on two standards: GSM and CDMA. We'll start with the CDMA standard, which is similar to GSM but uses digital channel division. This standard is not so popular in Russia, it operates at 450/850 MHz, one of the main CDMA providers is SCARTEL.
The more popular GSM operates at frequencies of 900 and 1800 MHz, this is the so-called European standard. In addition to it, there are also 850/1900 MHz GSM networks, but they are distributed only in the USA, Canada and some Latin American countries. Both 2G standards are used to exchange SMS messages, for voice calls, and for mobile access to the Internet using GPRS or EDGE technology. The largest GSM providers in the Russian Federation are MegaFon, MTS, Beeline, VimpelCom and Tele2. As we have already said, GSM coverage is present in almost all corners Russian Federation However, it is quite possible to find places where there is no connection at all. On average, the coverage of the Russian Federation with the GSM standard is 85%, however, some operators claim that their network operates throughout the country. Huge coverage and relatively inexpensive tariffs contributed to the fact that appeared in the Russian Federation.
A very common question is why the GSM standard uses 2 frequencies. All mobile phones are duplex devices, with normal telephone conversation You are using both of these frequencies. With some assumptions, we can say that one frequency transmits data from a mobile device to a network base station, and the second works in the opposite direction. The simultaneous use of these two channels allows you to speak and hear the interlocutor at the same time, if one frequency were used, then the principle of operation would be similar to a walkie-talkie, where there are 2 modes: “talk” or “listen”. By the way, building a GSM network is very similar to building a beehive, the network consists of honeycombs, with communication towers at the corners. The GSM standard uses towers with directional antennas that "look" into the cell. Your cell phone is connected to at least three nearby towers. This allows you to determine the approximate location of a subscriber in the GSM network, based on the signal strength from each of the cell towers.
3G - the next, third, generation cellular communication. There are several standards in which third generation networks operate, but we will consider the standard that works in Russia - WCDMA. This standard has a lot in common with CDMA standard, in particular, the same digital channel separation principle is used. In the Russian Federation, the State Commission for Radio Frequencies and Communications deals with frequency allocation and issues. According to the decision of the SCHR, the third generation of mobile communications operates at frequencies of 2000-2100 MHz. In Russia, the third generation works with various add-ons, such as HSUPA, HSPDA, HSPA +. Often these add-ons are mistakenly called 3.5G, although this generation of communication simply does not exist.
The main difference between 3G networks and networks of the previous generation is that they allow you to make video calls and use a fairly fast mobile internet, the data transfer rate here is 2-14 Mbps. However, it should be borne in mind that when moving, the data transfer rate may be slightly lower due to handovers. Handover is, in essence, switching the mobile device from one tower to another as it moves. It is they who can significantly degrade the quality of communication when driving at high speed.
This generation of communication is also well-spread, coverage is available in more than 120 major cities of Russia, the work of the largest operators is concentrated in densely populated areas. Major mobile operators such as MTS, VimpelCom, Beeline, MegaFon and SKYLINK provide 3G communication services.
4G
Russia is still far away. 4G is the most advanced mobile communication, using the latest technologies and providing record data transfer speeds. 4G works with two standards: LTE and Wi-Max. LTE operates in the frequency range of 791-862 MHz, while Wi-Max uses frequencies of 2500-2600 MHz. Although this standard is still new in many countries around the world, many even very advanced phones are not compatible with it, Russia boasts a fairly extensive 4G network. Coverage is available in Moscow, St. Petersburg, Samara, Ufa, Sochi, Novosibirsk and Krasnodar.
Freshtel and Yota were among the first 4G operators. Also, the fourth generation is actively developing in the Russian Federation with the support of such large operators as MTS and MegaFon. Very often, users are faced with the following problem: popular Yota operator offers access in the LTE standard, but in fact, according to the decision of the SCHR, it was allocated frequencies for Wi-Max. Therefore, confusion sometimes arises when it is necessary to know exactly which standard this or that operator works with. IN this case, Yota works in the LTE standard, but uses Wi-Max frequencies for data transmission.
Speaking of mobile communications and modern gadgets, it is difficult to ignore the domestic GLONASS navigation system. We should start with the fact that GLONASS differs from GPS not only in positioning accuracy, satellite orbit altitude and developer country, but also in operating frequencies. While GPS operates in three channels with frequencies of 1575.42, 1227.60 and 1176.45 MHz, GLONASS uses 2 channels and their frequencies are 1602-1615 and 1246-1256 MHz.
As a conclusion, we can say that the situation with mobile communications in Russia is quite good. The only downside to high level mobile fraud, as well as the fact that almost all operators are very sluggish in their fight against it. A distinctive feature of the Russian mobile communications market is that new technologies are being introduced quickly and at a high level, however, due to the high population density in cities and low in rural areas, it is not profitable to deploy coverage throughout the country, which is why most operators concentrate their activities in big cities.
The same frequency band is also used by television, Wi-Fi and Bluetooth. Among the frequency range, there are those that have been allocated specifically for mobile phones.
Historically, radio waves used for mobile systems communications in the countries of America, Europe, Africa and Asia differ from each other.
Technology and frequency standards
The first technology standard applied in the US for commercial use was AMPS with the 800 MHz band. In the countries of northern Europe, the NMT-450 technology was first introduced, the range of which was 450 MHz.
With the growing popularity of mobile phones, manufacturers faced a problem: they could not provide the service a large number of people. They had to develop existing systems and introduce new standard with a different frequency range.
In Japan and some European countries, the TACS standard has appeared with a 900 MHz band. The GSM standard that replaced the NMT-450 technology also used the 900 MHz band. As demand and the market for cell phones grew, providers acquired licenses to use the 1800 MHz band.
Lower frequencies allow providers to cover larger areas and more high frequencies enable communication to a larger number of customers in a smaller area.
Modern technology standards
The current generation of mobile devices operates mainly on the GSM standard. The UMTS standard is also gaining popularity. In some countries, technologies of ELT, 3G, 4G formats are used.
Each standard or format uses a frequency range of two frequencies. The low frequency range transmits information from the mobile device to the station, and the high frequency range transmits information from the station to the mobile.
Many GPS phones cover three frequency bands: 900, 1800, 1900 MHz or 850, 1800, 1900 MHz. These are the so-called tri-band phones or tri-band devices. With such a phone it is convenient to travel the world, and it does not require replacement when
moving to another country.
Mobile networks different formats can use the same frequencies. Such, for example, is the 800 MHz band used in at least four different formats.
The amount of frequencies available for use mobile devices, limited. This should be taken into account when the number of users increases. It means that base station can provide a limited number of people, and communication networks need to be constantly expanded.
Cellular phones of major providers in Russia operate at frequencies of 900 MHz and 1800 MHz. At the same time, Megafon, Beeline, MTS use both bands, and TELE 2 only use the 1800 MHz band.
Modern life is filled with various technological devices. People check every day email from their tablets and laptops, communicate in in social networks, call up their friends and relatives from anywhere in the world. Although only sixty years ago, the latter could only be dreamed of. After all, what functions the current smartphone performs, previously only a computer the size of a small cabinet could afford.
First cell phone
The first official cell phone was the device of the American engineer Martin Cooper, director of the mobile communications department of Motorola. On this device on April 3, 1973, he first called his competitor from Bell Laboratories Corporation, Joe Engel.
A phone with a protruding antenna weighed a little over one kilogram and worked in a talk mode for no more than an hour. None additional features the cellular device did not have, as well as a display familiar to a modern person, only twelve keys (10 digital, call and end a call).
By official version, the first commercial DynaTac cell phone was released on June 13, 1983 by Motorola.
However, there is every reason to say that the first cell phone was produced in the Soviet Union. It was the domestic radio engineer Leonid Kupriyanovich who created a sample of the LK-1 mobile phone, which was tested in 1957. The first "mobile phone" had a range of up to thirty kilometers, but its main disadvantage was the unacceptable weight for such a phone - three kilograms.
Therefore, a year later, Leonid Ivanovich improved the cell phone model. The updated device was the size of a pack of cigarettes and weighed only half a kilo. The telephone allowed not only to make outgoing calls, but also to receive incoming calls from stationary devices and street machines.
The first official American mobile phone put up for sale cost almost four thousand dollars! For example, "Toyota of the King" of the same year cost three hundred dollars cheaper. At the same time, the owner of the phone had to fork out another fifty dollars a month in a monthly fee.
The first mass-produced cell phone was the Nokia 1011. It already had a small display and worked in the GSM standard. The first foldable cell phone was the Motorola StarTAC.
Besides, mobile phone The Motorola StarTAC was among the very first phones to have a cell screen.
The first communicator was the Nokia 9000. It was made like a pencil case, with a screen on one side and a keyboard on the other. This communicator worked based on Intel processor 386.
A cell phone with an infrared port appeared in 2001 again under the Nokia brand. The first phone with an mp3 player was the Samsung SPH-M100.
The receiver can be either built-in or a separate device connected to a computer in the form special card inserted into the expansion slot.
The same principle of operation is used by many electronic devices – cell phones, wireless networks, garage door drives, remote controls remote control and so on. However, unlike the infrared communication that these devices rely on, RF communication does not require the mouse and receiver to be within an accessible distance of each other. The gadget's transmitter signal easily passes through obstacles in the form of a computer monitor or tabletop.
Wireless Mouse Synchronization
As in most modern computer mice, wireless models use in their work not a ball, but an optical system, which significantly increases the accuracy of the gadget. In addition, the optical system allows the user to apply wireless mouse on almost all surfaces, which is very important for a device that is not connected to a computer with a cable at least for a while.
Another advantage of radio frequency communication is the minimum energy consumption of radio transmitters and receivers, which, moreover, weigh little, cheap cost and can run on batteries.
Synchronization of a wireless mouse is needed for the interaction of its transmitter with the receiver, which should work on one channel, which is a combination of an identification code and a frequency. Synchronization prevents interference from other wireless devices and outside sources.
Each manufacturer equips their wireless mouse - some models (more expensive in the overall ranking) are sold already synchronized, and some need to be automatically synchronized by pressing certain buttons on the device. The data transmitted by the mouse to the receiver is protected by encryption mechanisms or frequency hopping technology.
Sources:
- how does a mouse work