So this is essentially a missle interceptor on the small scale? Looked more like some sort of grenade timed for the missle moreso. As was mentioned, this seems like a good but expensive answer but I could see a lot of friendly casualties from the blast if there were soldiers on foot nearby.
Probably the same thing if the rocket were to actually hit the tank itself. You're still looking at shrapnel in either case. At least with this option the tank can have its say in the matter.
This is just a copy of existing technology. U.S. has been developing tech like this for some time (as well as some other countries). If I'm not mistaken, automated defenses like this are to become standard armament in the upcoming iterations of upgrades to U.S. heavy machinery (light and heavy tanks, etc.).
I would not be surprised at all if a lot of this type of stuff has been in the works at Crane.
Reactive armor is different. It is contained in the armor itself and explodes out after being hit. Active armor no strike happens and the threat is eliminated before impact. This is not new tech and the US has been developing it too. I am interested to see how it does against a top down strike from a Javelin.