Nesteruk S. Digitally controlled multi-purpose antenna array

The object of the research is the characteristics of electromagnetic field radiated by a multi-purpose antenna array. The subject of the research is a multi-purpose antenna array consisting of flat spiral radiators located on a conformal surface and also algorithms of corresponding control of amplitude and phase of elements excitation. The methods of the research. In the process of research on the stage of preliminary estimation of the scanning properties of antenna array an engineering method of antenna pattern calculation was used which is based on the pattern multiplication theorem; calculation of the amplitudes and phases of the elements excitation currents was performed using the equivalent aperture method; research of electromagnetic properties of antenna array was realized with the help of generalized induced EMF method that used matrix theory, vector and linear algebra in its realization; the research of the whole array antenna properties was carried out with the help of computer modeling. The results of the research: the principle of multi-purpose array antenna construction is formulated, the method of the excitation currents amplitudes control in the elements of conformal array antenna is worked out and realized, the new type of flat spiral antenna winding is proposed, the mathematical model for the calculation of the proposed antenna element electromagnetic properties and the properties of the antenna array consisting of them is developed, the computer program that realizes the mathematical model is created, experimental researches of the created element properties is done, the mathematical model of digital control of the multi-purpose antenna array directional properties and amplitude control of the polarization parameters of the radiated field is created, the computer modeling of the multi-purpose antenna array is performed. The scientific novelty of the research is in the following: the method for the calculation and optimization of amplitude and phase excitation of the antenna array elements is proposed, the method of electromagnetic characteristics analysis of multiturn spiral antenna and antenna array consisting of such elements that is built on the basis of generalized induced EMF method is proposed and developed, the feasibility of radiation by proposed 4-turn spiral antenna element of the electromagnetic field with different types of polarization (linear, circular) and constant parameters of directional characteristic and input impedance is proved both theoretically and experimentally, the mathematical model for the calculation of the local phase center of the antenna with arbitrary polarization is developed, the method of digital control of antenna array characteristics in particular polarization ones within the main beam of the pattern and also the direction of maximal radiation is proposed. The results of the research are applied in industry on the enterprise LTD. «Uranis» (Sevastopol), and also enterprise of PLC. «Chernomortekhflot» (Odessa).