[adrian_b]

Over-the-horizon radars have very poor resolution, so they are useful only for early warning, not for guiding an interceptor.

For targeting at distance, you need antennas mounted on high masts or airborne radars.

[jjk166]

You don't need to target at distance, you are limited by the range of your interceptor. OTH tells you which interceptor battery needs to be looking where.