Simply pushing lots of CW power into the ether is the most inefficient method of jamming and rarely used because of this. More efficient is a tailored jamming system that is modulated in a way that causes problems in the demodulator of the receiver being jammed, usually by using a high peek pulse power at a critical frequency to the receiver demodulation. Even more efficient is to mess with the stages beyond the receiver such as sending valid modulation that mucks up the computer data processing.
Four US officials told NBC News that Moscow was concerned that the US would retaliate for the attacks in rebel-held eastern Ghouta, so it began signal jammer the GPS systems of some smaller drones. “GPS receivers in most drones can be fairly easily jammed,” said Humphreys, who warned that jammed drones may malfunction and even crash.
That’s why the US needs “penetrating” jammers, Bacon said: stealth aircraft that are harder – though hardly impossible – to target and which can slip into enemy airspace to conduct electronic warfare at shorter ranges. GPS denial is a becoming a huge issue for American military planners. Peer states, especially Russia, are already putting GPS spoofing and jamming tactics to work during various training events near their own borders. We have discussed this situation in great depth before, and I would suggest you read this article to understand just how deeply the loss of reliable global positioning system data can mean for the U.S. and its allies during a time of war, as well as what is being done to overcome such a monumental hurdle.
Never-the-less, straight-forward cell phone jammer is unlikely to pose the greatest threat, primarily because it is a very blunt instrument and not one that is likely to pass unnoticed. In the event of any abrupt loss or sudden degradation of the signal, a surprising range of devices will detect the problem, not just the GPS receivers themselves, and sound the alarm.
All four satellite navigation systems, the signals of which the Pole-21 must combat, use closely spaced frequencies, which end up in the interval from 1176.45 to 1575.42 MHz. The fact that even a transmitter with an output of a total of 20 watts in order to jam the radio signals in this range in a radius of 80 kilometers attests to the latest Russian system’s capabilities to create an impenetrable jamming dome