Modern navigation is impossible without global satellite systems, and the Russian system GLONASS occupies one of the key places in this area. Ensuring accurate positioning anywhere in the world, including high latitudes where other systems may operate less efficiently, requires a constant presence of a certain number of spacecraft in orbit. Many drivers who install trackers or use navigators wonder about the real number of working satellites.
The relevance of information about the composition of the group is important not only for engineers, but also for end users, since the speed of the “cold start” and the accuracy of the coordinates directly depend on the number of devices. At the moment, the orbital group has a sufficient number of devices to cover the entire territory of the Earth. However, the numbers are constantly changing: old satellites are de-orbited, and new ones are launched to replace them. Understanding the structure of this system helps to better understand the capabilities of navigation equipment.
In this article we will analyze in detail how many GLONASS satellites are in space right now, what types of devices provide navigation and how their number affects the operation of your car tracker. We will also consider the technical features of the orbits and the prospects for the development of the system in the coming years.
Current status of the orbital constellation
At the moment, the GLONASS orbital constellation is the second largest in the world after the American GPS. For full global coverage, the system requires 24 satellites, but to improve reliability and accuracy, especially in northern latitudes, their number usually exceeds this minimum. In normal operation, there are from 24 to 27 devices in orbit at the same time, ready to transmit navigation signals.
It is important to understand the difference between running devices and those that actually work. Some satellites may be in reserve, undergoing scheduled maintenance, or be taken out of service. Operational composition - these are exactly the devices that are broadcasting the signal right now and are used by navigation receivers. The status of each device is controlled by the information and analytical center.
⚠️ Attention: The number of active satellites is a dynamic value. At any moment, one device can be taken out for maintenance, and another, previously in reserve, can be put into operation. Therefore, the figures may fluctuate slightly throughout the year.
The stability of the constellation is ensured by the presence of backup satellites. If one of the main devices fails, its functions can be taken over by a backup one or the system will redistribute the load. For the user, this means that even in the event of temporary failures on one of the channels, communication with the system, as a rule, is not completely interrupted.
Launch history and evolution of devices
The history of the creation of the Russian satellite system goes back several decades. The first launches began in Soviet times, and since then several generations of spacecraft have changed. The evolution went from simple repeaters to complex navigation systems with an extended period of active existence. Each new type of satellite made its own adjustments to the overall size and effectiveness of the constellation.
The first generation, known as GLONASS, and the second generation, GLONASS-M, formed the basis of the system in the 2000s. However, it is the third generation devices, such as GLONASS-K and the latest GLONASS-K2, allow the system to compete with global analogues. They have more stable atomic clocks and better signal characteristics.
- 🚀 GLONASS (1982–2005): The basic series, which provided the initial deployment of the system, but had a short service life of about 3 years.
- 🛰️ GLONASS-M (2003–present): Upgraded version with extended service life up to 7 years and improved frequency stability.
- ⚡ GLONASS-K (2011–present): The devices are of a new type without a sealed housing, which reduces weight and increases service life to 10 years.
- 🆕 GLONASS-K2 (2022–present): The latest generation with the ability to transmit additional signals and increased positioning accuracy.
Generational change is a complex process that takes time. Old satellites gradually exhaust their resources and are removed from orbit, burning up in the atmosphere, and new ones take their places. It is thanks to the constant updating of the fleet that it is possible to maintain the declared number of operating satellites at the level necessary for global navigation.
Technical characteristics and types of orbits
The uniqueness of GLONASS lies not only in the number of satellites, but also in the configuration of their orbits. Unlike GPS, where satellites are located in six orbital planes, GLONASS devices are distributed over three planes. In each plane there are 8 satellites, evenly distributed in orbit. This configuration provides better visibility of satellites at high latitudes, which is critically important for Russia.
The orbital altitude is about 19,100 kilometers, and the period of revolution around the Earth is 11 hours 15 minutes. These parameters were calculated in such a way that at any point on the globe, at any time of the day, the user could “see” at least 4 satellites, which is the minimum necessary condition for determining coordinates.
| Parameter | Meaning | Description |
|---|---|---|
| Number of planes | 3 | The orbits are inclined at an angle of 64.8° |
| Satellites in the plane | 8 | Uniform distribution |
| Orbit altitude | ~19,100 km | Average value |
| Circulation period | 11h 15min | Sidereal period |
Each satellite is equipped with a high-precision atomic clock, which is the “heart” of the navigation system. It is the time synchronization between the satellites and the receiver that makes it possible to calculate the distance to the spacecraft. The error of these clocks is a fraction of a nanosecond, which in terms of distance gives high positioning accuracy.
The influence of the number of satellites on navigation accuracy
Users often underestimate how the number of visible satellites affects the performance of the navigator in the car. The minimum number of satellites to determine two-dimensional coordinates (latitude and longitude) is three, but to obtain altitude above sea level and improve accuracy, four or more are needed. Under ideal conditions, a modern receiver can “see” up to 12–15 GLONASS satellites simultaneously.
The more satellites are in the receiver's line of sight, the higher the geometric factor PDOP (Position Dilution of Precision). In simple words, if satellites are evenly spaced in the sky, rather than grouped in one sector, the accuracy of location increases significantly. A large number of devices in the group ensures that even in difficult conditions (urban buildings, forests) the signal will be stable.
⚠️ Attention: In the “concrete canyons” of large cities, the signal may be reflected from buildings (multipath effect). Having a large number of GLONASS satellites allows the receiver to filter out reflected signals and select direct signals, improving accuracy.
For commercial vehicles and monitoring systems, signal stability is critical. Loss of signal even for a short time can lead to breaks in the motion track. That is why modern telematics terminals support simultaneous work with GLONASS and GPS, summing the number of visible satellites of both systems to achieve maximum accuracy.
Comparison with other global systems
GLONASS does not exist in a vacuum. There are three more global systems operating in orbit: the American GPS, the European Galileo and the Chinese BeiDou. Comparing their groupings helps to understand the place of the Russian system in the global context. If GPS historically has a larger number of satellites (more than 30), then GLONASS benefits due to the optimal arrangement of orbits for the northern regions.
The Chinese BeiDou system is now the largest in terms of the number of devices, but their orbital configuration is more complex and includes satellites in geostationary orbits. The European Galileo, although younger, demonstrates high accuracy, but its constellation is still being built up to its full complement. GLONASS is fully equipped and ready to work 24/7.
- 🇺🇸 GPS (USA): More than 30 satellites, high accuracy in mid-latitudes, de facto standard for most civilian devices.
- 🇨🇳 BeiDou (China): The largest grouping, focused on the Asia-Pacific region, is actively developing.
- 🇪🇺 Galileo (Europe): High accuracy, civilian control, gradual increase in the number of devices.
Modern navigation chips are multi-system. This means that your smartphone or car navigator simultaneously receives signals from all available systems. To the user, this looks like a single navigation process, but “under the hood” the device selects the best signals from GLONASS, GPS and others, ignoring noise and interference.
Development prospects and modernization
The development of the system does not stop. The plans of Roscosmos and industry enterprises include further updating of the group with new generation devices GLONASS-K2. These satellites will be able to transmit new navigation signals that will be more resistant to interference and provide centimeter positioning accuracy. This will open up opportunities for unmanned vehicles and precision agriculture.
The possibility of increasing the number of satellites in the constellation to create backup locations and cover “dead zones” in difficult terrain is also being considered. By 2030, it is planned to increase the number of spacecraft in the system to 26-28 units in an active state, which will become a new record for Russian navigation.
An important area is the development of ground infrastructure. Even the most advanced satellite will not work without a network of ground correction and control stations. Modernization of mission control centers makes it possible to respond more quickly to changes in the orbital constellation and quickly introduce new satellites into service.
Frequently asked questions (FAQ)
How many minimum GLONASS satellites are needed for the navigator to work?
To determine coordinates (latitude and longitude), you need to see at least 3 satellites. However, to obtain the correct altitude above sea level and increase the accuracy of calculations, a signal from at least 4 satellites is required. In real-world conditions, modern receivers try to use 6–10 satellites to minimize errors.
Why does the navigator show fewer satellites than there are in orbit?
There are about 24–27 satellites in orbit, but the Earth is round, and at any given time, only those satellites that are above the horizon are visible above a particular point on the surface. Usually these are 8–12 satellites. The rest are currently on the other side of the planet.
Does GLONASS work without the Internet?
Yes, the satellite signal is received directly from space and does not require an Internet connection. The Internet may only be needed to download maps or to transmit your coordinates to the monitoring server (in the case of trackers), but the process of determining the location itself is autonomous.
Does weather affect the number of visible satellites?
GLONASS signals pass through clouds, rain and snow with virtually no loss. However, severe conditions such as thunderstorms or heavy snow may weaken the signal slightly. The main obstacles are physical objects: buildings, mountains, dense forest and tunnels.