(I have no information and thus no opinion on this being a thing that happens but)
constantly keeping the cell antenna and CPU awake would probably do it. it's a BIG part of why weak cell signal and lots of noise at e.g. conventions drains your phone many times faster than normal, even when you're not using it. you could probably do that just by sending junk data to everyone occasionally, or delaying valid data to prevent going into sleep modes for longer periods.
If you ever forget to put your phone in Airplane Mode when flying (and you survive the flight!), you will notice that the battery is surprisingly depleted.
I think it has to do with the phone constantly renegotiating with cell towers along the route.
I've seen similar behaviour when a hurricane took out power to a local tower, and it was intermittently restored.
It might be possible to emulate that in a controlled environment/area.
Not exactly. The phone needs to transmit with enough power to communicate with the tower. When connected to the tower, the tower is constantly monitoring the signal and sending back information to the cell phone to tell it how much power it needs (without using more than it needs and wasting battery life).
If a phone isn’t connecting to any towers (like on a plane) it assumes it is out of range and is blasting out max power trying to find something to connect to. During hurricanes, many towers are down, which can overburden adjacent towers as well (since each tower only has a certain number of slots/channels it can handle). It means that you may not be able to communicate with your closest tower, since it is down, but you also may not be able to communicate with the next nearest tower, since it at capacity for current users, which puts you in a longer distance higher transmit power situation.
From what I have heard, those Stingrays act as fake towers, so I would assume they could set them to always tell the phones it needs max transmit power.
