The Tale of the Pockmarked Goby. The described action is practically impracticable at the modern technical level.

Dear David, let you be taken by helicopter to the forest, or better to the steppe / desert for ... thirty kilometers and try to return to the starting point using the "terrain pattern" without a GPS Tracker and a compass. In the best case, you will spend twice as much time .... To understand where to go, you need to understand where you are and have AZIMUTH.

Timur, you are right it is so. Gps

GPRS is a "protocol" for data transmission in the GSM cellular network

All drones are perfectly oriented on the terrain map. They analyze the photo if the visibility is normal and perfectly tied to the terrain without satellite navigation systems. At least they will return to the base without problems.

Dear "Listener", I am not a radio engineer, although I have a basic technical aviation education, and I "conjecture" on it :))
Your words - ".. if the transmission channels are suppressed, then the product will continue to execute the programmed program ..", in its essence (and the designer's intention) is correct.
But there is .. "BUT". Namely, if the signal is changed, the on-board UAV system will not determine the "moment of truth" and will consider everything as a normal situation.
But even with the loss of the signal from the satellite and GPRS, the UAV will in fact "understand" that an "emergency" has occurred and decide to return to the base, but it needs to understand the location in coordinates.
The infamous American Tomahawks. if the system loses GPRS, it immediately adjusts via satellite. Yes, there is a moment that the "Tomahawk" determines the "drawing" of the surface and height, and including, most likely, the presence of a compass can go according to the program. But it is unlikely that such a system exists in the UAV.
The global trend tends to substitute the UAV control signal.

In fact, the Aviation Lover has described everything correctly, with the exception of a few details. 1. If the product loses the positioning signal, then it executes the nested program as far as possible. As a rule, this is a return to base. The GPS signal is not secure in the full sense, since it is not possible to suppress it in the entire range, but this does not mean that it is not possible to do this for a specific area or object ... 2. Protected signals, as a rule, are command signals, as a rule are encoded by hardware, for this type of product it is primarily the ability to receive data with a strong level of interference, but if the transmission channels are suppressed, then the product will continue to execute the programmed program. The data transmitted from the product is usually not protected ... Something like this ... in general ...) So what was described could very well be ..)

Solovyov told you this on a zomboyaschik?

Dear Volodya. Guided by the GPRS | Glonass satellite navigation system, the UAV (drone) automatically returns to the point from which it was launched.
But the signal is substituted and imitates the signal of the "master" - this is in one case.
In the second, the UAV loses its GPRS signal and communication with the satellite, which leads to the loss of "understanding the point of location".
If necessary, the operator can also initiate a controlled interception. And then there is a system that determines the location of the UAV (drone) operator.
They don't come back yet ....)))

The Germans came up with a system that makes the drone return to the launch site, thereby making this type of weapon completely useless.