Synthesis Method of a Multibeam Digital Antenna Array by Given Amplitude Directivity Pattern

Amplitude-phase synthesis method of a multibeam digital antenna array according to a given amplitude directivity pattern with the same directional characteristics in a given sector of electrical scanning is proposed. To solve the synthesis problem, a mathematical model of the antenna array in a coordinate system invariant to the direction of orientation of the beam is introduced. Expressions are given that ensure the transformation of the geometry of the digital antenna array into the proposed coordinate system, as well as integral objective functions of the digital antenna array synthesis problem, in which integration is carried out only in a limited spatial region or along the half-power level of the main beam. The general idea of constructing the desired amplitude-phase distribution in the aperture of the digital antenna array and the binary mask of antenna elements used in the formation of each formed beam as a combination of parameter functions determined during the solution of the search engine optimization problem is substantiated. The possibility of compensating for beam departures during electronic scanning is taken. To solve the considered problem of digital antenna array synthesis, it is proposed to use a genetic algorithm. It is shown that the proposed method provides stabilization of the beam width in all azimuthal directions relative to the direction of orientation of the beam, as well as stabilization of the gain in a wide scanning sector.