A cellular phone is a full-duplex device that utilises two frequencies at the same time. One is for talking while the other is for listening. The signals are handled at the same time. There are signal cell phone jammer that can only block one of the frequencies at a time, which results to the blocking of both because the phone thinks that there is no service in the area because it can only get one of the frequencies.
That even state intelligence services have had difficulty in determining the source of the jamming and whether or not it was deliberate, highlights how effective these tactics can be even during an uneasy peace. With electronic and cyber assaults, Russia has found an effective way to disrupt the military and government activities of its regional opponents while maintaining a surprising amount of plausible deniability
There are different types of cell phone 4G jammer on the market today. Some devices can only block a single frequency while there are complex ones that can block several types of networks at the same time. The latter models can automatically switch from different networks to find an open signal. Higher end devices can block all frequencies at the same time while there are others that can be tuned to a specific frequency.
For a radio jammer to work, it needs to be fairly close to the signal its crew wants to disrupt. The Avtobaza, for one, can detect targets up to 93 miles away, according to Air Power Australia, an independent think tank specializing in military electronic systems. Jamming requires more power than detecting does, so the range at which the Avtobaza can disrupt a drone is certainly shorter than 90 miles.
coloSimply put, they emit random static or noise on a sweeping range of frequencies, strong enough that a device closeby cannot connect to what it supposed to. Kind of like being beside a running car engine, with the hood open, while trying to talk to someone on the phone. The local noise becomes overpowering so the device can’t make its usual connection. By quickly covering a range of frequencies, they effectively block a device from operating normally.