The idea is to catch enemy rockets using information from military radars because this is the best possible source of information (other sources is considered as well, for example visual scanning with OpenCV detecting), then transmit information to drone using LoRa, then the drone is approaching to the rocket seing it from thermographic camera. When the distance between drone and rocket will be as close as 1 meter then to blow up the fougasse for not letting the rocket to blow my house. Sounds simple and very cheap, but why this is not a common approach?
Wikipedia doesn’t list the flight speed of any of the compatible rockets, but it does list the “muzzle velocity”as 690m/s. My guess is they go faster than that once the rocket motors fire up, but even if they just fly at 690m/s it’s far from “simple” to intercept them with an accuracy down around 1m.
690m/s doesn’t give you many milliseconds between “it’s too far away for my explosive to damage” and “it flew right past me and hit eimrine’s house already”.
If your camera is running 25 frames a second it’ll have moved 26m between frames. My inexpensive thermal camera from Adafruit can only do 16 frames per second, so it’d be 43m between frames. And I only get 32x24 pixels with it, so it’s angular resolution isn’t going to make intercepting something moving that gas easy, even if it’s coming directly towards me.
It’s _possible_ maybe, but I doubt you’d even get close using hobby grade drones and diy grade electronics.