The ARM guidance head is usually based on monopulse method (same as used with the KRUG system [YOU SHOULD KNOW IT ALREADY!!!]), as the targeted SAM system can be switched off at any moment.
In fact most if not all modern radar guided missiles use a monopulse antenna design. Let's see if someone starts building AESA-radared missiles ...
Thanks for the pic BTW, I had not seen that antenna before.
Agree, monopulse design has succeeded all the others in newer systems...
2K11 KRUG (SA-4)
S-200 Vega (SA-5)
2K12 KUB (SA-6)
9K33 OSA (SA-8)
All Patriot designs.
We, SAM Fire Control Officers know this antenna design (somehow) very well...