GPS and GLONASS jammers for cars

On the Internet, recently a device called the GPS signal suppressor (jammer) is gaining popularity. It is supposed to be used for shelter from GLONASS. What this device represents and how the signal is suppressed is discussed in this article.

Installation of GLONASS

Recently, new domestic cars began to be manufactured with the built-in GLONASS system, which began to operate on the territory of Russia from the beginning of 2015. Prior to this, only the Global Positioning System GPS was used. On the one hand, having installed GLONASS on the car, the driver is guaranteed to receive assistance in case of road accidents. The system will automatically detect the accident and inform all emergency response services that those taking urgent measures to rescue people and fix the road accident. On the other hand, the GLONASS installation is seen as an encroachment on the driver's rights, and many do not want to use it.

Thus methods of signal suppression are used the most various, depending on imagination of drivers.

1. The antenna is spoiled.
2. The antenna is wrapped in foil, trying to create an effect of screening.
3. Screen the terminal itself.
4. They spoil the terminal.
5. Trying to implement a microcircuit.
6. The SIM card is corrupted or removed.

And, of course, that the installation of GLONASS on the car did not detect it, use sensational jammers. In addition to buying appliances on the Internet, domestic craftsmen are trying to even construct the appropriate structures themselves.

GPS and GLONASS jammer

Suppressors of radio signals, 3G, cellular communications, Bluetooth and, of course, GLONASS in principle have the same design, differing only in the frequency range. For all these devices it is different, so depending on what is configured, it will neutralize.

A GPS jamming device consists of the following components:

• VCO;
• Antenna, preferably SMA;
• Tuning scheme;
• Amplifying cascade of signals of radio frequencies.

The circuit of the device may be open or with feedback. Any radio amateur, having a scheme (and you can get it, just "zagugliv"), can easily assemble the device. But for this you need to understand something in radio engineering.

For those who do not understand these issues, it remains to purchase a ready-made device.

The struggle of the tracking system and drivers will worsen

Motorists rush to use the device for personal protection, preserving privacy, for example, to hide from tracking tracking in vehicle fleets. But it is also quite possible to use it for criminal purposes, for example, to deactivate the anti-theft system.

Track all vehicles is very difficult. This is used by unscrupulous drivers, acquiring such funds. Especially they become relevant in connection with the advent along with GPS, the GLONASS system, Galilleo, eCall.

Most recently, the GLONASS system started, and although it is not yet common on all cars, this process is rapidly gaining momentum. In the coming years, the European system, which is being standardized, will also start operating.

But the "people's struggle" is coming into force to interfere with signals. So, the GPS and GLONASS jammer for cars is capable not only to destroy the radio signals available in a certain car, but also to interfere with the traffic around it.

This situation can not leave indifferent developers of global positioning systems. Therefore, one can certainly expect the introduction of countermeasures on their part.

Laboratory research in Germany

To this end, a number of engineers began to study the structure of unwanted signals. The frequencies were studied by a spectro-analyzer, a recording controlled by means of programs and radio communications was conducted.

As a result, it was reported that most low-cost suppressors emit a chirp pulse, the others generate harmonic oscillations in the pass band and have a resonant thermally dependent frequency. And one and the other types of jammers create concentrated noise, but the first ones cause more destruction of GPS signals.

A chirp pulse is created by a generator that is controlled by voltage. It is linear with a positive bi-directional or unidirectional sweep. The negative slope is too large, so they were neglected in modeling. To obtain synchronization information, time-domain analysis was also performed.

Laboratory GATE

Various interference tests were conducted to measure the effect of suppressor signals on signals from global positioning systems under real conditions. This became achievable in the Gate lab, where they created a unique environment for this kind of testing. It has eight virtual satellites located around the test zone. There they play different scenarios. The signals are transmitted at all frequencies. Satellites simulate the movement of real Galilleo. Two ground stations receive and process signals.

Also used a multifrequency receiver, capable of tracking the signals of various global positioning systems. Different modes were considered, depending on the required frequency ranges.

Results of measurements of GPS suppressors

To analyze how the GPS jammer (and GLONASS, as well as Galileo and other global positioning systems) will affect the receiver, measurements were taken. The distance was set at 1.2 kilometers. At the same time, different suppressors were used. The antennas of the receivers were mounted on the roof of the car. In order for the GPS, GLONASS, and Galileo jammer to be correctly set, a distance meter with a GPS receiver was used. The attenuation of reception is measured by the ratio of the noise density at the input.

Numerous measurements were carried out with decreasing and increasing power. Their results showed that the GPS and GLONASS jamming device, as well as Galilleo and other systems, could have a devastating effect on receivers that are up to a kilometer away. The source of interference makes the location impossible within a radius of two hundred meters.

Development of detection mechanisms for suppressors

Thus, jammers carry a serious threat to present and future navigation systems. Their use is prohibited and punishable by law.

Developed to obtain a mechanism for detecting jammers. For testing at special points, detectors were used, where interference was recorded. Decoupling of highways is considered successful for installing the latter.

Several receivers were used for recording. The device was tried to detect by means of the signal-to-noise ratio of the muffler. Measurements have shown that the detection of hijackers creating interference is possible. For monitoring, special receivers are also created, capable of detecting and reporting interference.

Conclusion

The practice of signal masters has shown that barbaric ways of damaging the design, as a rule, result in the dismissal of an unfair employee. Disconnecting from the on-board network will be a useless task, since the device is equipped with its own battery. Screening also will not bring success.

There is a GPS and GLONASS jammer. Reviews of some drivers who tested the device in practice, in others cause hope for a successful similar use.

However, on the other hand, active work is under way to develop a mechanism for detecting suppressors.

While the GPS and GLONASS jammer, including those made by themselves, is being used with impunity (basically, truck drivers are interested in this). But it is not known how long this will last. After all, it is clear that the ways of detecting signal suppressors are being developed. And if the devices are found, the drivers will have to bear responsibility for this.