Frequency jammers have a very clear and simple goal: to prevent communication on certain frequencies. However, since it is not easy to prevent the device from communicating with other devices, the solution to prevent this type of information transmission is very simple, and is similar to a DDoS attack: introducing noise at a specified frequency, useless information soaks the tape to prevent Reach real information. The jammer can be used to interfere with various types of communications or devices from cellular networks, radar, Bluetooth, GPS, infrared, etc. Despite their wide range of uses, all inhibitors are very simple. They are based on a circuit with an oscillator that generates a signal, a noise generator, an amplifier stage to provide enough power for the signal, and finally one or more antennas to transmit the signal generated by the card.
As mentioned at the beginning, there are inhibitors of various sizes. From mobile phones to handbags, it always depends on the frequency (one or more) and range (from a few meters to more than one kilometer) to be scanned. Of course, if someone wants to know the origin of these devices, we will have to go back to war, especially World War II, when both sides used portable jammer to disrupt enemy communications. In the case of frequency interference, it occurs like many other advances, including technological advances: there are always people who use them improperly. Interfering transmitters can have legitimate uses, such as protecting certain buildings, for example to prevent remote activation of explosives. However, in many cases, even if the person who uses the inhibitor does not realize it, they may not use them properly.
The use of interfering agents became popular in several universities in Spain a few years ago (Oviedo, Seville, Zaragoza or Valencia are some examples). For what? Because the use of this technology is for the benefit of students who do not want to go through the pinganillos who are not in contact with people who give test answers outside, some teachers or faculty and staff run on the middle street through frequency interference, hindering To communicate with the outside world.
In these cases, there are several problems: First, the range of action of the suppressor is uncontrollable, beyond the performance of the instrument that determines its impact, which may damage users who are not in the test room. . On the other hand, it is not easy to block all the frequencies available for mobile phones, because they vary according to the operator of each mobile phone, and can even use WLAN or Bluetooth network for communication. In addition to improper use of frequency interference, there is another problem involving robbery in private homes or other places. Alarms connected through cellular networks have recently become popular because they are easy to install and cheap. In this case, the problem is that the thief can go to the place where the inhibitor was robbed (usually the alarm uses the 900 MHz band), so the alarm cannot communicate with the control panel.
Fortunately, alert companies have realized that the use of traditional cellular networks may be interfered with by frequency interference (as we will see below, it is easily available on the Internet). Therefore, they first suggested either installing an alarm that communicates via a fixed network, which is obviously easily cut off by the cable, or recommending the use of a network like Sigfox, which cannot actually be blocked due to the use of very narrow frequencies.