Building your own 4G LTE jammer?

Hi, I recently built a wifi jammer for all channels and then fit it nicely in a case... This time I want to build a 4G LTE jammer somehow. However, I don't know how I can do this now? Unfortunately, I can't find much on the internet either. PS...I am aware of the illegal effects.

Topsignaljammer  2022.3

From a legal standpoint, I can only oppose it. It's probably okay to scramble the WLAN (although of course it's already illegal), since it's an open band, and you're probably using some kind of allowed WLAN module, and then you're also locally limited in terms of transmission strength. So verifiability should be difficult (and intentional). LTE may vary. By the way, the Federal Network Agency has measuring stations all over Germany for monitoring the radio area. If you find something interesting, you might be targeted.

Otherwise, you need a radio transmitter, and software-defined radios (SDRs) are often used for this purpose. A relatively cheap (300 EUR) is eg HackRF. With enough transmit power, you can certainly interfere with something, but of course it's best to take a closer look. For example, the type of modulation, possible pilots, the structure of the packets... Of course, it should be noted that each network provider has its own frequency range. You won't be able (at least with such cheap hardware) to be able to interfere with more than one at the same time.

But the easiest way is to spend dozens of euros to buy a wifi jammer, which is much cheaper than doing it yourself