Description: Analyzing the basic methods and features of determining the directional characteristics of axis-symmetric antenna arrays, which include convex antenna arrays, in the near, far and intermediate zones, distinguish a number of their differences from the directional characteristics of flat antenna arrays. These differences are mainly due to the fact that in determining the directional characteristics, axisymmetric antenna arrays should be considered as a system of extraneous non-collinear electric (magnetic) currents on the convex surface of the antenna. The application of this approach requires the use of the basics of electrodynamics in solving problems of determining the directional characteristics of such antenna systems. However, the different orientation of the partial radiation patterns of the emitters does not allow the application of the diagram multiplication theorem and the inverse methods of determining the radiation characteristics. In addition, in the known works are not fully represented mathematical models of the fields of elementary sources in the far, intermediate and near areas with respect to convex antenna arrays. The mathematical model of the electric and magnetic components of the radiation field of elements of a convex antenna array is developed. The obtained expressions allow us to construct algorithms for numerical simulation of the radiation field of a convex antenna array in the far, intermediate and near regions. During the development of the mathematical model, it was considered that an internal problem for each of the dipoles entering the convex antenna array was solved and the distribution of currents in them was found. Moreover, the dependence of the complex amplitude of the current on time is considered harmonious. The mathematical expressions given in the article can be the basis for the method of analysis of the directivity characteristics of three-dimensional models of a convex antenna array in the far, intermediate and near regions.
Keywords: convex antenna array, elementary source, Hertz dipole, electric and magnetic field, near zone, far zone, intermediate zone
1. Voskresenskyi, D.Y., Ponomarev, L.Y. and Fylyppov, V.S. (1978), “Vypuklye skanyruiushchye antenny (osnovy teoryy y metody rascheta)” [Convex scanning antennas (basic theory and calculation methods)], Soviet radio, Moscow, 304 p.
2. Voskresenskyi, D.Y., Kremenetskyi, S.D. and Hrynev, A.Yu. (1981), “Antenny y ustroistva SVCh (proektyrovanye fazyro-vannykh antennykh reshetok)” [Antennas and microwave devices (Phased array antenna design)], Radio i svyaz, Moscow, 432 p.
3. Josefsson, L. and Persson, P. (2006), Conformal array theory and design, IEEE press. Whiley-Interscience publication, New Jersey, 488 p.
4. Krylov, H.N. (1965), “Tsylyndrycheskye koltsevye y vertykalnye antenny” [Cylindrical, ring and vertical antennas], Energiya, Moscow, 204 p.
5. Feld, Ya.N. and Benenson, L.S. (1955), “Antenny santymetrovykh y detsymetrovykh voln” [Antennas of centimeter and decimeter waves], VVIA, Moscow, 207 p.
6. Voskresenskyi, D.Y. Stepanenko, V.Y. and Fylyppov, V.S. (2003), “Ustroistva SVCh. Proektyrovanye fazyrovannykh antennykh reshetok” [Microwave devices. Phased Array Design], Radiotehnika, Moscow, 474 p.
7. Stretton, J. (1948), “Teoryia elektromahnetyzma” [Theory of Electromagnetism], OGIZ, Moscow-Leningrad, 538 p.
8. Zamiatyn, V.Y. and Trubaev, S.Y. (1992), “Elektrodynamyka y skhemotekhnyka SVCh. Chast 1. Elektrodynamyka y rasprostranenye radyovoln” [Electrodynamics and circuitry microwave. Part 1. Electrodynamics and radio wave propagation], VIRTA, Kharkiv, 434 p.
9. Jackson, J. (1965), “Klassycheskaia elektrodynamyka” [Classical electrodynamics], Mir, Moscow, 705 p.
10. Nykolskyi, V.V. and Nykolskaia, T.Y. (1989), “Elektrodynamyka y rasprostranenye radyovoln” [Electrodynamics and radio wave propagation], Nauka, Moscow, 544 p.
11. Pchelyn, B.K. (1968), “Vektornyi analyz dlia ynzhenerov-elektrykov y radystov” [Vector analysis for electrical engi-neers and radio operators], Energiya, Moscow, 256 p.
12. Syrenko, Yu.K., Sukharevsky, Y.V., Sukharevsky, O.Y. and Yashyna, N.P. (2000), “Fundamentalnye y prykladnye zadachy teoryy rasseianyia elektromahnytnykh voln” [Fundamental and applied problems of the theory of scattering of electro-magnetic waves], Krok, Kharkiv, 344 p.
13. Riapolov, I.Ye., Vasylets, V.A., Sukharevsky, O.Y. and Tkachuk, K.I. (2014), “Vysokochastotnyi metod rascheta vtorychnoho yzluchenyia modely fiuzeliazha bespylotnoho letatelnoho apparata” [High-frequency method of calculating secon-dary radiation model fuselage UAV], Systems of Arms and Military Equipment, No. 1(37), pp. 222-225.
14. Riapolov, I.Ye., Vasylets, V.A. and Sukharevskyi, O.Y. (2014), “Vysokochastotnyi metod rascheta rasseianyia vtorych-noho yzluchenyia dyelektrycheskykh chastei modely bespylotnoho letatelnoho apparata” [High-frequency method for calculating the scattering of secondary radiation dielectric parts of the model UAV], Information Processing Systems, No. 2(118), pp. 58-62.