Overhead Tracking Method for Electronically Scanned Array Antennas based on Virtual Guidance

The operational range of a typical radar or satellite ground antenna is limited to a portion of the celestial sphere at the observation station. However, for ground antennas used in target tracking, it is not only required to track the target for as long as possible, but also necessary to have the capability of overhead tracking, as the aircraft is closest to the ground station and the signal is strongest when it passes through the zenith. This paper analyzes the issue of overhead tracking for antennas, proposes a virtual guidance overhead tracking method suitable for electronically scanned arrays, and converts the path planning problem generated by virtual guidance into a quadratic programming problem under linear constraints, which is solved using the interior-point method. The computational results show that the virtual guidance generated by this method is smooth and gradual, with significantly lower requirements for servo dynamic performance than the antenna design values, and the spatial angular deviation between the antenna normal and the target is much smaller than the electronic scanning range.