Well.....
The tilt of the RADAR antenna has nothing to do with the pitch of the aircraft, as the IRU, in its determination of where the horizon is, tells the stabilization circuitry where 'level' is.
So, let's say the aircraft's pitch is exactly on the horizon...that is, Zero degrees...and let's say the RADAR antenna is tilted up 4 degrees (four degrees above the horizon). Now, you pitch the aircraft up four degrees above the horizon. The RADAR antenna pitch stabilization circuitry maintains four degrees above the horizon (it moves downward as the aircraft pitches up)...based on the IRU's reference of Zero pitch.
Does this answer your question?
PantLoad