Description: The variants of realization in the meter range radar of radio technical troops of wavelengths channels in angular bearing direction of the targets are considered. For describing the expected amplitude-phase distribution of the echo signal at the vertical opening of the antenna, using a number of modern methods of monitoring the radar detection zones at the position is proposed. In the case of a small number of layers of the radar antenna array, under conditions of significant reflection of radio waves by the earth's surface, ambiguity of angular measurements occurs (false angular bearings are formed). For eliminating false information, a number of methods are proposed that are based on additional space-time modulation of sounding signals. Temporal modulation can be accomplished by changing the carrier frequency of the emitted signals and space modulation by operatively changing the shape of the antenna pattern in the irradiation target. Methods and results of calculations of quality indicators of measurements at use of the offered variants of construction of channels in angular direction bearing targets are given. Optimization of space (angular) processing allows to provide (with respect to the P-18 radar and its modifications) an energy gain of up to 3 dB. The root-mean-square errors of angular bearing (at angles above 5–6 degrees) can be reduced to fractions of a degree. The probability of false angular bearings (in the range of 0-30 degree angles) can be no more than 0.01 - 0.05. It is possible to resolve targets at the corner of the site, to begin with, under two hypotheses: a) one target; b) more than one target. The presented method can serve as a basis for the analysis of potential possibilities for measuring the angular coordinates of the targets in the existing and perspective survey radars of radio-technical troops in the presence of significant rereflection of radio waves by the earth surface and can also be used for the rational choice of rational technical solutions.
Keywords: radar of the meter wavelength range, measurement of elevation coordinates of targets, false elevation bearings, space-time modulation of the probing signals, angular resolution of the radar
1. Shirman, Ya.D., Bagdasaryan, S.T. and Malyarenko, A.S. (2007), “Radioelektronnyie sistemy: Osnovy postroeniya i teoriya. Spravochnik. Izd. 2-e, pererab. i dop.” [Radio electronic systems: Bases of construction and theory. Reference book. Edition is second, processed and complemented], Radio Engineering, Moscow, 512 p.
2. Skolnik, M.I. (2008), Radar Handbook. ISBN 0071485473, Third Ed. McGraw-HillBook Company, Boston, 149 p.
3. The official site of Keysight Technologies (2017), 5990-7036RURU (5990-5442EN/5990-5442RURU), available at: www.keysight.com.
4. Litvinov, V.V., Zyukin, V.F. and Araslanov, M.R. (2009), “Obzor rabot VIRTA PVO po bezobletnomu kontrolyu zon obnaruzheniya RLS” [Review of works of VIRTA PVO on control of areas of discovery radar], Applied Radio Electronics, No. 4, pp. 469-476.
5. Zyukin, V.F., Belavin, A.V. and Svistunov, D.Yu. (2013), “Trebovaniya k udaleniyu imitatorov aktivnyih pomeh pri poligonnyih ispyitaniyah RLS” [Requirement to the delete of active noise simulators at ground tests radar], Information Processing Systems, No. 1(108), pp. 56-60.
6. Gorobets, N.N. and Trivaylo, A.V. (2010), Fields of a rectangular loop antenna in the near-field zone, Telecommunication and Radio Engineering, No. 69(11), pp. 947-957.
7. Gorobets, N.N. and Trivaylo, A.V. (2009), Curved Dipole in the Near-Field and Far-Fiel Zones of Observation, ICAT, 7-th International Conference on Antenna Theory and Techniques: conf. proc., 6-9 October, Lviv, Ukraine, pp. 102-104.
8. Gregson, S.F. and Hindman, G.E. (2009), Conical Near-Field Antenna Measurements (AMTA Corner), Antennas and Propagation Magazine, IEEE, No. 1(51), pp. 193-201.
9. Bielavin, O.V., Kamaltynov, H.H. and Maliarenko, O.S. (2012), “Eksperymentalno-rozrakhunkovyi metod otsinky parametriv zon vyiavlennia pervynnykh ta vtorynnykh RLS” [Experimentally-calculation method of estimation of parameters of areas of discovery primary and second radar], Science and Technology of the Air Force of Ukraine, No. 3(9), pp. 69-73.
10. Bielavin, O.V. (2016), “Eksperymentalno-analitychnyi sposib vyznachennia nyzhnoi kraiky zony vyiavlennia povitrianykh obiektiv perspektyvnoiu RLS MR-1” [Experimentally analytical method of determination of lower limit of area of exposure of air objects by perspective radar of MR-1], Weapons Systems and Military Equipment, No. 4(48), pp. 83-87.
11. Christian, W. (2018), Ingenieurburo, available at: www.slideshare.net/hossamzein/radartutorial.eu.
12. Fusco, M. and Vertucci, R. (2016), Radar system on field-performance check, Proc. 2016 IEEE Metrology for Aerospace (MetroAeroSpace), 21-23 June, Florence, Italy, pp. 71-74. https://doi.org/10.1109/MetroAeroSpace.2016.7573188.
13. Bech, J. and Chau, J.L. (2012), Doppler Radar Observations – Weather Radar, Wind Profiler, Ionospheric Radar, and Other Advanced Applications, 470 р., available at: https://www.intechopen.com/books/doppler-radar-observations-weather-radar-wind-profiler-ionospheric-radar-and-other-advanced-applications.