This has been a solved problem since the early DSP times. Actually, weather has never been a real issue for Satellite Early Warning Systems......simply because you would need the ballistic missiles to fly under the weather to avoid lighting up the sats like a Christmas tree..
How have you reached this conclusion, friend? The technology for this is well understood and in use by multiple nations (including China) for 50 years now..
Fair enough, I'll withdraw that particular objection. However, I will question how the OPIR solves the dilemma caused by FOBS in particular. Even if you detect it early, the fact that it's attacking from a vector which circumvents the first layers of defense (e.g. sea based AEGIS portrayed in the marketing slide) still remains the actual problem.