V.A. Voloshin, D.D. Gabrielyan, A.Yu. Larin, O.V. Ovodov
The synthesis of the amplitude-phase distribution will not only preserve but also to a large extent becoming more relevant in the theory and technique of antennas. It is due to new opportunities in the construction of digital beamforming antenna, almost removing restrictions on the choice of the amplitude-phase distribution, and complexity of shape of the boundary of the radiating apertures. This paper deals with methods for solving the problem of synthesis of amplitude-phase distribution in the aperture with arbitrary form boundaries when setting requirements for directivity and the nature of the spatial distribution of the side lobe level.
Synthesis of amplitude-phase distribution in the aperture with an arbitrary form boundary may be based on different approaches. In particular, this formulation of the basis of construction methods for the synthesis of the amplitude-phase distribution may be well-known method of synthesis for a given volumetric radiation pattern, a method of converting the amplitude and phase distribution in major sections and the method of auxiliary ring currents. In the second case based on two given distributions recalculation of complex amplitudes of excitation in radiators of arbitrary form aperture from maintenance condition of equivalent amplitude-phase distribution in orthogonal planes is made.
The third case focused on synthesis of amplitude-phase distribution in aperture of elliptical form. Solution of SLAE rather of complex amplitudes of excitation of auxiliary circular currents based on given regularity of side lobes level changes in cut plane of volume radiation pattern is made.
In this paper for the aperture with elliptical shape of the boundary presents a comparative analysis of advantages and disadvantages of each of the three methods applied to the synthesis of the amplitude-phase distribution in the aperture with an arbitrary form boundary. The results can be generalized to the case of apertures with the boundary as a broken line and an irregular arrangement of the radiators in the aperture.