Level and cross-level stabilization technique for search radar antennas

Claim 1

A motion stabilized high-frequency antenna system comprising; an antenna platform; a high frequency antenna having a primary focusing structure moveable about both elevation and optical axes of said antenna, and a secondary focusing structure rigidly mounted on said antenna platform wherein said primary focusing structure is comprised of a high frequency feedhorn directed at an attached subreflector, said feed horn and subreflector movable in unison with respect to said secondary focusing structure; means for sensing the position of said secondary focusing structure with respect to a desired position and for generating rotating means positioning signals proportional to the elevation axis and optical axis components of the position difference between said sensed position and said desired position, said optical axis positioning signal indicating a direction of motion opposite to said sensed position difference, and said elevation axis positioning signal indicating the same direction of motion as said sensed position difference; and means connected to said sensing means for rotating said primary focusing structure separately and independently about said optical axis and said elevation axis of said antenna, whereby a change proportional to said sensed position difference as indicated by said positioning signals is produced in the position of said primary focusing structure.