This paper introduces a novel adaptive continuous beam steering (ACBS) solution for quasi-optical antenna technologies. The main advantages of this solution compared to discontinuous beam switching approaches are small steering angle steps (high resolution), improved beam crossing level and lower RF losses. This solution is based on a phase correcting aperture transfer function and the relation between a focal array amplitude tapering and its phase center displacement. The proposed solution is verified by comparing its results with 3D full-wave simulations. With a 2x2 focal source array illuminating a Fresnel dielectric lens, it is possible to achieve a scanning range of 1.6° with a steering angle step of 0.3° and a beam crossing level of 0.2dB. The ACBS solution can be integrated into active antennas for self-alignment purposes.