Thieves can obtain illegal GSM jammer. They range in size from small portable devices to large briefcases. They send signals at GSM frequencies. This prevents GSM tracking devices in the vehicle from sending and receiving messages.
Yes, the signals transmitted by these illegal devices form bubbles around the vehicle, tracking the device "silently" very effectively and no one knows what happened. This has recently happened in Congress, with large jammers deployed throughout the US Congress that can effectively block all GSM signals in the House of Representatives.
Okay. He can The tracking device has three main requirements to resist interference. First, the device must be able to detect signal interference. Next, he needs to send an urgent message telling someone "I'm trapped." The third and most important thing is that you need to be able to send this urgent message at a frequency different from the blocking frequency. Beware of scammers-the solution will fail if there is no other unobstructed frequency.