The global satellite system GLONASS is. Glonass or GPS - pros and cons. Glonass for transport control

It is still difficult to believe that in our age of “wild” commerce there is an absolutely free (if technical means are available) opportunity to determine your location anywhere in the world. This is one of the greatest inventions of the 20th century! This multi-billion-dollar system (today there are several of them) was conceived primarily in the interests of defense (and science), but very little time passed and almost every person began to use it every day. By GPS navigator we mean a special radio receiver for determining the geographic coordinates of the current location (positioning).

I was prompted to write this post by a phrase from a well-known tourist in narrow circles about the Garmin Etrex 30x navigator.
Here is a quote from his article: "Satellite system: GPS/GPS+Glonass/Demo mode. Doesn't it make you think that only Glonass can't be turned on? So it's not there. The instructions don't say anything about this. You can take the Garmin in one hand just for fun , and in another smartphone with Glonass, open the satellite display screen and try to find similar ones. This is just emulation, so it doesn’t matter whether you install GPS or GPS+GLONASS."
What do you think of this statement? Just don’t rush to check right away. Since the concepts “GPS”, “GLONASS” and “Garmin” appear here, we will have to cover the topic completely.

1 - GPS
The first global positioning system was the American NAVSTAR system, which dates back to 1973. Already in 1978, the first satellite was launched, which can be considered the beginning of the era of the Global Positioning System (GPS), and in 1993 the orbital constellation consisted of 24 spacecraft (SV), but only in 2000 (after the deactivation of the selective access mode) regular operation began for civilian users.
NAVSTAR satellites are located at an altitude of 20,200 km with an inclination of 55° (in six planes) and an orbital period of 11 hours 58 minutes. GPS uses the 1984 World Geodetic System (WGS-84), which has become the standard coordinate system for the entire world. ALL navigators determine the location (show coordinates) in this system by default.

The constellation currently consists of 32 satellites. The earliest in the system is from November 22, 1993, the latest (last) is December 9, 2015.


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2 - GLONASS
The domestic navigation system began with the Cicada system consisting of four satellites in 1979. The GLONASS system was put into trial operation in 1993. In 1995, a full orbital constellation was deployed (24 Glonass satellites of the first generation) and normal operation of the system began. Since 2004, new Glonass-M satellites have been launched, which broadcast two civil signals at frequencies L1 and L2.
GLONASS satellites are located at an altitude of 19,400 km with an inclination of 64.8° (in three planes) and a period of 11 hours 15 minutes.

The constellation currently consists of 24 satellites. The earliest in the system is from April 3, 2007, the latest (last) is October 16, 2017.


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Table with GLONASS satellite numbers. There is a GLONASS number and a COSMOS number. Our smartphones have completely different satellite numbers. From 1 this is GPS, from 68 - GLONASS.
Moreover, they are even different in the navigator and smartphone.

Now let's look at the Orbitron program. On the afternoon of April 4, 10 GLONASS satellites “flew” across the sky in Izhevsk.

Or in another view - on a map. There is all the data about each satellite.

The main difference between the two systems is the signal and its structure.
The GPS system uses code division. A standard precision coded signal (C/A code) transmitted in the L1 band (1575.42 MHz). The signals are modulated by pseudo-random sequences of two types: C/A code and P code. C/A - a publicly available code - is a PRN with a repetition period of 1023 cycles and a pulse repetition rate of 1.023 MHz.
In the GLONASS system, frequency division of channels. All satellites use the same pseudo-random code sequence to transmit clear signals, but each satellite transmits on a different frequency using a 15-channel frequency division. Navigation radio signals with frequency division in two bands: L1 (1.6 GHz) and L2 (1.25 GHz).
The structure of the signal is also different. To describe the motion of satellites in orbit, fundamentally different mathematical models. For GPS, this is a model in osculating elements. This model implies that the trajectory of the satellite is divided into sections in which the movements are described by the Keplerian model, the parameters of which change over time. The GLONASS system uses a differential motion model.
Now to the question of the possibility of combination. 2011 passed under the auspices of GLONASS support. When designing receivers, it was important to overcome the problems of incompatibility of hardware support for GLONASS and GPS. That is, the frequency-modulated GLONASS signal required a wider frequency band than the pulse-code modulation signals used by GPS, bandpass filters with different centers frequencies and at different speeds transmission of signal elements. To save energy in navigators, it is recommended to enable the "GPS only" mode.

3 - Garmin
The American manufacturer of portable navigation devices has gained worldwide fame primarily thanks to tourist GPS navigators(GpsMap, eTrex, Oregon, Montana, Dakota series) and car navigators, sports watches and echo sounders. The headquarters is located in Olathe, Kansas. Since 2011, Garmin began selling GPSMAP 62stc navigators with the ability to receive and process signals from GPS and GLONASS satellites. However, information about the chip manufacturers used has become a trade secret.

The use of dual-system receivers helps improve the quality of navigation in real conditions, but dual-system does not affect the accuracy of coordinate determination. The insufficient signal from the satellites of one system in a given place and at a given time is compensated by the satellites of another system. The maximum number of “visible” satellites in the sky under ideal conditions: GPS - 13, GLONASS - 10. It is for this reason that most conventional (non-geodetic) receivers have 24 channels.

Here are the test results from 2016. For your information, NAP-4 and NAP-5 use navigation receivers from the Izhevsk radio plant MNP-M7 and MNP-M9.1, respectively.

Conclusions. The best results in positioning accuracy along the experiment route were shown by NAP-1, NAP-2, NAP-4. All NAPs have positioning accuracy sufficient for confident navigation in all modes. At the same time, the positioning accuracy in GPS mode and in combined mode is slightly better than in GLONASS mode.
The results of NAP-3 with experimental software in terms of horizontal positioning accuracy in all modes are worse than those of the same receiver with standard software (NAP-2). There is no such difference in height accuracy. The exception is large errors in the combined mode, caused by a one-time failure in the operation of the NAP, which led to strong deviations.
The results of NAP-5 are generally worse than those of the previous generation NAP from the same manufacturer (NAP-4). There was a slight improvement in horizontal positioning accuracy in GLONASS mode. ()

The navigator antenna receives satellite signals and transmits them to the receiver, which processes them. Chips for navigation devices that support GPS+Glonass are produced today by many companies: Qualcomm (SiRFatlas V, drol_links Garmin has a STA8088EXG receiver from one of the largest European companies STMicroelectronics.

Conclusions for Garmin navigator users:
1. In Garmin navigators and watches (after 2011), it became possible to select (turn on signal reception and processing) either GPS or GPS+GLONASS. GLONASS is not provided separately due to the fact that it is Garmin (how can the Americans only turn on something Russian?)
2. In ideal or close to ideal conditions (steppe, plain), the second system is not necessary. In the mountains, cities and northern latitudes - very desirable. But the energy consumption will be greater.
3. If smartphone manufacturers were able to cram this feature into their compact devices, then why didn’t Garmin do it?
Good luck!

To determine location, global navigation satellite systems (GNSS) are currently the most widely used: Russian GLONASS and American GPS.

This is primarily due to the availability and miniaturization of navigation devices. Today, a personal navigator has become as common a device as mobile phone or computer.

In addition, GNSS have high accuracy in determining navigation parameters and have global coverage.

How GNSS works

The principle of determining the consumer's location is quite simple, like everything ingenious. Knowing the locations of the satellites (the information is contained in the satellite’s navigation signal) and the distance to them, you can use simple algebraic calculations to unambiguously determine your location in a certain three-dimensional coordinate system. Ideally, to obtain three consumer coordinates, it is enough to know information about three navigation spacecraft (NSV).

However, not everything is so simple in practice. The thing is that GNSS implements the principle of query-free range measurements, i.e. The transit time of the information signal from the satellite to the consumer is determined. And in order to determine this time with high accuracy, it is necessary to synchronize the clocks of the satellite and the consumer’s navigation equipment (CNA). In this regard, to find the coordinates and mismatch between the NAP and GNSS clocks, it is necessary to know the parameters of at least 4 satellites.

The GLONASS space segment is an orbital constellation of 24 satellites located in three planes of 8 satellites each with an orbital altitude of 19,100 km and an inclination of 64.8°. In addition, there must be one backup satellite in each plane. The satellites emit radio signals at their own frequencies.

The ground segment consists of a cosmodrome, a command and measurement complex and a control center.

And finally, the segment that is of greatest interest to the consumer is the user segment, which includes NAP.

GNSS today

Modern domestic receivers for civilian use, installed on vehicle control systems, operate using GLONASS (L1-band, ST-code) and GPS (L1, C/A-code) signals and allow determination (at a probability level of 0.95 at the value of the geometric factor no more than 3):

coordinates in plan with an error of no more than 10 m and in height - no more than 15 m;

planned speed with an error of no more than 0.15 m/s.

At the moment, the use of single-system GNSS receivers in NAP (GLONASS only or GPS only) has practically disappeared. First of all, this is due to the fact that in the modern urban landscape, shadowing of the radio visibility of satellites is inevitable. An example is the operation of the NAP near the wall of a house, when physically half of the sky is closed. Ultimately, this leads to the fact that the ability to accurately position an object is reduced, and sometimes becomes impossible. The use of two navigation systems improves and expands the experience for consumers.

In such conditions, the use of GLONASS in conjunction with GPS significantly increases the reliability and reliability of the NAP in determining coordinates.

Today many people know what GLONASS is. But how exactly this system works, what it is intended for and what is necessary for its effective use is often left out of the question.

To regard the GLONASS system simply as a satellite navigation system means to extremely simplify its functionality. Today it can be used not only by the military (as it was originally intended), but also by owners of commercial enterprises, as well as ordinary car enthusiasts.

GLONASS is a Russian development that provides accurate positioning of an object in space with minimal error. To determine coordinates, special equipment is used, which, with the support of ground infrastructure, communicates with a network of satellites placed in low-Earth orbit.

Operating principle of the system:

• A transmitting and receiving device, a terminal, is installed on the object whose coordinates need to be determined.
• For positioning, the terminal sends a request to satellites. The more satellites respond to the request (ideally at least 4), the more accurately the coordinates will be determined.
• The response signal arrives at the terminal, software package which analyzes the delay time for different satellites. Based on the analysis of the response information, the coordinates of the object on which the receiving equipment is installed are determined.

With constant operation of the terminal (i.e. regularly sending requests and analyzing responses), the GLONASS system can determine not only the position, but also the speed of movement of the object. When moving, the positioning accuracy decreases, but still remains sufficient for the navigation equipment to link the coordinates of the object to an electronic map of the area and build a route.

Comparison with the main analogue - the GPS system

Give a complete answer to the question “What is GLONASS?” impossible without comparing it with its “closest competitor” - the GPS global positioning system. Work on both systems began in the USSR and the USA at approximately the same time - in the early 80s of the last century. After satellite navigation left the complete control of the military and began to be used for commercial purposes, GLONASS and GPS developed according to fairly similar scenarios.

Both systems operate on the basis of constellations of 24 satellites in geostationary orbits. But they also have differences:

• Russian satellites move in 3 planes (respectively, 8 devices per orbit).
• GPS satellites have 4 orbits with 6 satellites in each.
• The positioning error of GPS is somewhat lower, but both systems determine coordinates quite accurately.
• The main advantage of GPS is almost 100% coverage of the globe. GLONASS completely covers the territory of the Russian Federation, but outside Russian Federation There are areas where the signal from satellites is very weak or completely absent.
• There are also nuances technical nature: the US service uses CDMA encoding, the Russian one uses more complex and therefore more energy-intensive FDMA encoding. Because of this, the service life of GLONASS satellites is reduced, so there is a need for more frequent launches of equipment into orbit.

It is difficult to talk about a clear advantage of one of the two navigation systems described. Moreover, most often equipment for remote positioning is combined: it can work with both GPS satellites and GLONASS equipment.

Scope of application

Equipment and software, which makes it possible to determine the location of an object using a satellite network, can solve several problems.

The main function performed by GLONASS household terminals is global navigation for transport. Such equipment is an improved map: the coordinates determined by the terminal are superimposed on the terrain plan and show the optimal direction of movement to a given point.

In addition, the equipment can be used:

• In transport monitoring systems. Enterprises that have to track the movement of multiple vehicles (passenger buses, trucks) on regular or irregular routes have the opportunity to see where a particular vehicle is at any time. For this purpose, cars are equipped with GLONASS terminals that connect to the software.

In addition to directly monitoring the movement of equipment, the dispatcher is able to monitor compliance with the speed limit, the driver’s work/rest schedule, the safety of cargo in the refrigerated compartments of refrigerators, and the level of fuel in tanks/tanks. To solve these problems, additional equipment can be installed and connected to the terminal connectors.

• In self-driving cars. For drones satellite system navigation along with sensors that read environmental parameters - the main control elements. Such equipment is already being produced and undergoing testing, including on Russian highways. Experts predict an increase in the share of unmanned vehicles on the roads in the near future.
• In anti-theft systems. GLONASS tracker, secretly installed in a car, can sound an alarm if the car’s coordinates change without the owner’s knowledge. In addition, the equipment can periodically send messages indicating the location of the car - this will make it easier for the owner or law enforcement officials to find a stolen car.

GLONASS for transport control

While GPS traditionally remains more popular in the segment of navigation systems for drivers, GLONASS occupies a more profitable niche in the commercial segment. This is due to the active development of remote transport monitoring systems.

Such systems traditionally include a network of GLONASS terminals installed on equipment and dispatch software. The implementation of monitoring involves its integration with the logistics scheme of the enterprise.

The main task is to coordinate the work of the transport department and track the movement of vehicles carrying passengers or cargo in real time. The coordinates of each vehicle are determined by satellite at a set interval and superimposed on the map, so the dispatcher or department head receives the most objective and timely information.

In addition, transport monitoring can be used for:

• Increasing the level of discipline. The navigation terminal tracks the movement of the vehicle along the route, eliminating inappropriate use of equipment and downtime. Any unplanned stop or deviation from the route must be motivated by the driver, and the dispatcher can contact him immediately if a violation is detected.
• Improving traffic safety and reducing accidents. The GLONASS system makes it possible to control the speed of movement, signaling to the dispatcher if the speed is exceeded. In addition, monitoring allows you to track overtime to ensure compliance with the work and rest schedule. This not only reduces the risk of accidents due to fatigue, but also ensures that there are no fines when checking tachograph readings.
• Fuel level control. Installing fuel level sensors and connecting them to the terminal almost completely eliminates the possibility of theft of fuel and lubricants.

What is ERA GLONASS?

The coordinate determination system with the help of GLONASS satellites can solve another problem - emergency notification of an accident. To do this, an ERA-GLONASS (UVEOS) terminal with a SIM card for working in a mobile network and a “panic button” for calling the dispatcher are installed in the car.

If the machine is equipped with ERA-GLONASS during production or delivery to the Russian Federation, then in addition to the terminal with a call button, sensors are also installed in it that react to damage and automatically sound an alarm in the event of an impact or a rollover.

The main task of the system is to notify emergency services(DPS traffic police, Ministry of Emergency Situations, Ambulance) about an accident, providing them with the coordinates of the accident site and basic information about the car and passengers. In this case, the signal about the incident is received by the call center dispatcher, who also transmits the received information to the rescue services.

Features of emergency notification

ERA-GLONASS works according to a simple principle:

• The alarm can be activated automatically (the impact/rollover sensor was triggered) or manually (the driver or one of the passengers pressed the button).
• After the signal arrives at the call center, the dispatcher communicates with the machine in voice mode (the terminal design includes a speaker and microphone). This is necessary to avoid false calls or accidental activation of the SOS button.
• If no response was received, or the driver confirmed the accident, the information is transmitted to rescue services.

The automatic operation of the system minimizes the time between an accident and the arrival of help at the scene. This significantly reduces road deaths, because ambulances and rescuers have more time to provide qualified assistance.

The reliability of the system is very high: the terminals are supplied with autonomous power sources, and even if the on-board network is de-energized during an accident, they remain operational for at least several hours. This is quite enough to determine coordinates, as well as to communicate with the call center.

The SIM card installed in the terminal provides stable communication with the dispatcher wherever there is mobile network coverage. To ensure reliable communication, the devices are equipped with efficient antennas For cellular communications and GLONASS satellites. Usually when good quality signal data is transmitted via GPRS (a 3G modem is used); in case of problems with communication, the terminal can send service SMS with basic information for emergency services.

Both the communication session with the dispatcher and the call for help by activating emergency notification of rescue services are completely free.

What data does it collect?

UVEOS are required to be installed for all vehicles that are put into circulation on the territory of the Russian Federation. But if new cars are equipped with terminals, panic buttons and sensors in production, then when importing equipment, the owner is obliged to install ERA-GLONASS at his own expense, otherwise it will be impossible to operate the car in the Russian Federation.

One of the arguments against the equipment of an ERA-GLONASS vehicle is the possible tracking of the movement of equipment via a satellite network (i.e., illegal transfer of personal data to intelligence agencies) or wiretapping of the interior. In practice, the tracking function is not implemented in the terminals, so it is impossible to track the movement of the car without the owner’s knowledge.

According to the manufacturers, the terminal collects and transmits only the following data:

• Coordinates of the accident site.
• Speed ​​at the time of the accident.
• Alarm trigger type (shock/flip sensor, forced call).
• Vehicle information: number, make, engine type (gasoline/diesel).
• Number of seat belts fastened.

Also, the information received by the dispatcher during a conversation with the driver is transmitted to the rescue services.

Today GLONASS is not just a navigator that will help you not get lost on unfamiliar roads. The possibilities of satellite positioning are much wider, and both an ordinary car owner and the head of a commercial enterprise with an extensive fleet of vehicles can take advantage of them.

For a long time, the global geopositioning system GPS, created in the United States, was the only one available to ordinary users. But even taking into account the fact that the accuracy of civilian devices was initially lower compared to military analogues, it was sufficient for both navigation and tracking the coordinates of cars.

However, the Soviet Union developed its own coordinate determination system, known today as GLONASS. Despite the similar principle of operation (calculation of time intervals between signals from satellites is used), GLONASS has serious practical differences from GPS, due to both development conditions and practical implementation.

• GLONASS is more accurate in conditions northern regions . This is explained by the fact that significant military groups of the USSR, and subsequently Russia, were located precisely in the north of the country. Therefore, the mechanics of GLONASS were calculated taking into account accuracy in such conditions.
• For uninterrupted operation of the GLONASS systemno correction stations required. To provide GPS accuracy, whose satellites are stationary relative to the Earth, a chain of geostationary stations is needed to monitor inevitable deviations. In turn, GLONASS satellites are mobile relative to the Earth, so the problem of correcting coordinates is absent initially.

For civilian use, this difference is noticeable. For example, in Sweden 10 years ago, GLONASS was actively used, despite the large amount of already existing GPS equipment. A considerable part of the territory of this country lies at the latitudes of the Russian North, and the advantages of GLONASS in such conditions are obvious: the lower the satellite’s inclination to the horizon, the more accurately the coordinates and speed of movement can be calculated with equal accuracy in estimating the time intervals between their signals (set by the navigator equipment).

So which is better?

It is enough to evaluate the modern telematics systems market to get the correct answer to this question. By using a connection to GPS and GLONASS satellites simultaneously in a navigation or security system, three main advantages can be achieved.

• High accuracy. The system, analyzing current data, can select the most correct of the available ones. For example, at the latitude of Moscow, GPS now provides maximum accuracy, while in Murmansk GLONASS will become the leader in this parameter.
• Maximum reliability. Both systems operate on different channels, therefore, when faced with deliberate jamming or interference from outsiders in the GPS range (as in the more common one), the system will retain the ability to geoposition via the GLONASS network.
• Independence. Since both GPS and GLONASS are originally military systems, the user may face deprivation of access to one of the networks. To do this, the developer only needs to introduce software restrictions into the implementation of the communication protocol. For the Russian consumer, GLONASS is becoming, to some extent, in a backup way work in case of GPS unavailability.

That is why the Caesar Satellite systems offered by us, in all modifications, use dual geopositioning, supplemented by tracking coordinates via cellular base stations.

How truly reliable geolocation works

Let's look at the operation of a reliable GPS/GLONASS tracking system using the Cesar Tracker A as an example.

The system is in sleep mode, not transmitting data to cellular network and turning off GPS and GLONASS receivers. This is necessary to save the maximum possible resource of the built-in battery, respectively, to ensure the greatest autonomy of the system that protects your car. In most cases, the battery lasts for 2 years. If you need to locate your car, for example, if it is stolen, you need to contact the Caesar Satellite security center. Our employees switch the system to an active state and receive data about the location of the car.

During the transition to active mode, three independent processes occur simultaneously:

• Triggered GPS receiver, analyzing the coordinates using your geopositioning program. If less than three satellites are detected within a given period of time, the system is considered unavailable. The coordinates are determined using the GLONASS channel in a similar way.
• The tracker compares data from both systems. If a sufficient number of satellites have been detected in each, the tracker selects the data that it considers more reliable and accurate. This is especially true in case of active electronic countermeasures - jamming or substitution of the GPS signal.
• The GSM module processes geopositioning data via LBS (cellular base stations). This method is considered the least accurate and is used only if both GPS and GLONASS are not available.

Thus, modern system tracking has triple reliability, using three geopositioning systems separately. But, naturally, it is the GPS/GLONASS support in the tracker design that ensures maximum accuracy.

Application in monitoring systems

Unlike beacons, monitoring systems used in commercial vehicles constantly monitor the location of the vehicle and its current speed. With this application, the advantages of dual GPS/GLONASS geopositioning are revealed even more fully. Duplication of systems allows:

• support monitoring in case of short-term problems with signal reception from GPS or GLONASS;
• maintain high accuracy regardless of flight direction. Using a system like CS Logistic GLONASS PRO, you can confidently operate flights from Chukotka to Rostov-on-Don, maintaining full control over transport throughout the entire route;
• protect commercial vehicles from opening and theft. Caesar Satellite servers receive real-time information about the time and exact location of the car;
• effectively counteract hijackers. The system saves internal memory the maximum possible amount of data even if the communication channel with the server is completely unavailable. Information begins to be transmitted at the slightest interruption of radio jamming.

By choosing a GPS/GLONASS system, you provide yourself with the best service and security capabilities in comparison with systems that use only one of the geopositioning methods.

The GLONASS system is the largest navigation system that allows you to track the location of various objects. The project, launched in 1982, is still actively developing and improving. Moreover, work is being done both on the technical support of GLONASS and on the infrastructure that allows more and more people to use the system. So, if in the first years of the complex’s existence, navigation through satellites was used mainly in solving military problems, today GLONASS is a technological positioning tool that has become mandatory in the life of millions of civilian users.

Global Satellite Navigation Systems

Due to the technological complexity of global satellite positioning, today only two systems can fully correspond to this name - GLONASS and GPS. The first is Russian, and the second is the fruit of American developers. From a technical point of view, GLONASS is a complex of specialized hardware located both in orbit and on the ground.

To communicate with satellites, special sensors and receivers are used to read the signals and generate location data based on them. To calculate time parameters, special ones are used. They are used to determine the position of an object, taking into account the broadcast and processing of radio waves. Reducing errors allows for more reliable calculation of positioning parameters.

Satellite navigation features

The range of tasks of global satellite navigation systems includes determining the exact location of ground objects. In addition to geographic location, global navigation satellite systems allow you to take into account time, route, speed and other parameters. These tasks are realized through satellites located at different points above the earth's surface.

The use of global navigation is not limited to the transportation industry. Satellites help in search and rescue operations, geodetic and construction work, and coordination and maintenance of other space stations and vehicles is also essential. The military industry is also not left without the support of a system for similar purposes, providing a secure signal designed specifically for authorized equipment of the Ministry of Defense.

GLONASS system

The system began full operation only in 2010, although attempts to put the complex into active operation have been made since 1995. The problems were largely associated with the low durability of the satellites used.

On this moment GLONASS consists of 24 satellites that operate at different points in orbit. In general, the navigation infrastructure can be represented by three components: a control complex (provides control of the grouping in orbit), as well as navigation technical means users.

24 satellites, each of which has its own constant altitude, are divided into several categories. There are 12 satellites for each hemisphere. Through satellite orbits, a grid is formed over the earth's surface, through the signals of which precise coordinates are determined. In addition, satellite GLONASS also has several backup facilities. They are also each in their own orbit and are not idle. Their tasks include expanding coverage over a specific region and replacing failing satellites.

GPS system

The American analogue of GLONASS is a GPS system, which also began its work in the 1980s, but only since 2000 has the accuracy of determining coordinates made it possible for it to become widespread among consumers. Today, GPS satellites guarantee accuracy up to 2-3 m. The delay in the development of navigation capabilities has long been due to artificial positioning limitations. Nevertheless, their removal made it possible to determine the coordinates with maximum accuracy. Even when synchronized with miniature receivers, a result corresponding to GLONASS is achieved.

Differences between GLONASS and GPS

There are several differences between navigation systems. In particular, there is a difference in the nature of the arrangement and movement of satellites in orbits. In the GLONASS complex they move along three planes (eight satellites for each), and the GPS system provides for work in six planes (about four per plane). Thus, Russian system provides wider coverage of the ground area, which is reflected in higher accuracy. However, in practice, the short-term “life” of domestic satellites does not allow using the full potential of the GLONASS system. GPS, in turn, maintains high accuracy due to the redundant number of satellites. Nevertheless, the Russian complex regularly introduces new satellites, both for targeted use and as backup support.

Also applicable different methods signal coding - Americans use CDMA code, and in GLONASS - FDMA. When receivers calculate positioning data, the Russian satellite system provides a more complex model. As a result, using GLONASS requires high energy consumption, which is reflected in the dimensions of the devices.

What do GLONASS capabilities allow?

Among the basic tasks of the system is determining the coordinates of an object capable of interacting with GLONASS. GPS in this sense performs similar tasks. In particular, the movement parameters of ground, sea and air objects are calculated. In a few seconds vehicle, provided by an appropriate navigator, can calculate the characteristics of its own motion.

At the same time, the use of global navigation has already become mandatory for certain categories of transport. If in the 2000s the spread of satellite positioning related to the control of certain strategic objects, today receivers are equipped with ships and aircraft, public transport, etc. In the near future, it is possible that all private cars will be required to be provided with GLONASS navigators.

What devices work with GLONASS

The system is capable of providing continuous global service to all categories of consumers without exception, regardless of climatic, territorial and time conditions. Like services GPS systems, GLONASS navigator is provided free of charge and anywhere in the world.

Devices that can receive satellite signals include not only on-board navigation aids and GPS receivers, but also Cell Phones. Data on location, direction and speed of movement are sent to a special server via GSM operator networks. Helps in using satellite navigation capabilities special program GLONASS and various applications that process maps.

Combo receivers

The territorial expansion of satellite navigation has led to the merging of the two systems from the consumer's point of view. In practice, GLONASS devices are often complemented by GPS and vice versa, which increases the accuracy of positioning and timing parameters. Technically, this is realized through two sensors integrated into one navigator. Based on this idea, combined receivers are produced that work simultaneously with GLONASS, GPS systems and related equipment.

In addition to increasing the accuracy of determination, such a symbiosis makes it possible to track location when the satellites of one of the systems are not detected. The minimum number of orbital objects, the “visibility” of which is required for the navigator to operate, is three units. So, if, for example, the GLONASS program becomes unavailable, then GPS satellites will come to the rescue.

Other satellite navigation systems

The European Union, as well as India and China, are developing projects similar in scale to GLONASS and GPS. plans to implement a Galileo system consisting of 30 satellites, which will achieve unrivaled accuracy. In India, it is planned to launch the IRNSS system, operating through seven satellites. The navigation complex is oriented towards domestic use. The Compass system from Chinese developers should consist of two segments. The first will include 5 satellites, and the second - 30. Accordingly, the authors of the project envision two service formats.