Defense against on FT-2000 AWACS killer

Hi, I am a new bee.
Read about China’s FT-2000 SAM. It is supposed to be based SA-10(Launch type) and Patriot (track-via-missile seeker) . Range is supposed to be a max of 100Km and Max altitude of 20,000Mt(not sure). Homes in on 2HHz to 18GHz EM Radiation.

I wanted to know, How effective is it ?, and what are the counter measures against this type of SAM’s.
Baliga