Anyone have any idea how downlink signal jammer can work in LTE?
I am also interested…
Using random noise generator at downlink frequencies, i believe.
Use noise generator is not good for those OFDM signals. I have tried many kind of methods to blocking LTE/NR signals. LTE/NR base station transmit PSS, SSS act as the sync signal for UE. they have complicated combination (504/1008), so it is hard to be simple randomized noise blocked. Even if you increase the transmit power to very large scale(multiple W or several tens of W).
I have tried to use signalling mode to do such work, it works quite well : generate fake LTE base station downlink signal at the frequency which you want to blocking. but it only has Tx without Rx, when UE detected this signal at this frequency point, it will try to sync or update to this cell, but because we do not give any respond to it,
the UE will abort this frequency and try to searching for other frequency to find proper carriers. I tried with this with only -10 dbm signals, it can make UE lost sync at current frequency points within at lease 10 meters.