Regularities of the Generation of Plane Fields on Matrix Radar Complexes with Ring Antenna Arrays

In the practical application of aircraft, there may be situations when it is not possible to resolve radar target signals in the measurement channels of range, speed and angular coordinates in the on-board radar system. In these situations, it is advisable to use angular estimation procedures with super-resolution in the onboard radar system. Various methods and algorithms of angular estimation with super-resolution are known, each of which has its own advantages and disadvantages. At the same time, there is no information in the available scientific and technical literature about the algorithms of angular estimation with super-resolution used in the onboard radar system, knowledge of which is necessary when designing promising onboard radar systems. The article systematizes and analyzes the methods and algorithms of angular estimation with super-resolution. The classification of methods of angular estimation with superresolution is given. The generalized information about the known one-dimensional and twodimensional methods and algorithms of angular estimation is given. The algorithms proposed for use in flat antenna arrays, concentric ring antenna arrays, ring antenna arrays, round four-quadrant antenna arrays, flat antenna arrays with a total output signal are considered. It is noted that the features of the construction of radar homing heads include a reduction in the total number of information processing channels achieved by combining antenna elements into sublattices, the output signals of which are used to estimate the angular coordinates of radiation sources. The specificity of such antenna arrays is that the antenna sublattices have radiation patterns that are narrower than those of weakly directed antenna elements. In addition, the distance between the antenna modules can significantly exceed the distance between the antenna elements in a conventional antenna array and at the same time significantly exceed the wavelength size. To determine the possibilities of applying in practice the algorithms of angular two-dimensional estimation with super-resolution considered in the article in the onboard radar system, it is necessary to conduct special studies.

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Switched ring antenna array with electronic scanning

Antennas ◽

10.18127/j03209601-202103-01 ◽

2021 ◽

Author(s):

V. M. Gavrilov ◽

R. N. Glukhov ◽

V. K. Dementiev ◽

N. N. Korneeva

Keyword(s):

Antenna Array ◽

Antenna Arrays ◽

Side Lobe ◽

Directional Pattern ◽

Base Station ◽

Main Lobe ◽

Printed Antenna ◽

Frequency Range ◽

Beam Position ◽

Ring Antenna

For operation in the frequency range of 5,1–5,9 GHz, a directional antenna device has been developed for use as part of a base station in a stationary point-to-multipoint system with a controlled beam position. The antenna device is a switched, broadband, ring antenna array with electronic scanning in the azimuthal plane. Its distinctive feature is high gain of the radiating elements, which are used as linear printed antenna arrays with parallel power supply. The required directional characteristics and matching of the emitters have been achieved in the process of parametric synthesis carried out using the CST MS program. In a given frequency range, the emitters are characterized by the following parameters: width of the main lobe of the directional pattern in the E-plane is 6,6…7,5 deg; level of the first side lobe in the E-plane is 0…–11,4 dB; width of the main lobe of the directional pattern in the H-plane is 53,2…73,4 deg; level of the first side lobe in the H-plane is –23,4…–26,4 dB; gain is 17,0…17,5 dB; the reflection coefficient at the input of the emitters does not exceed 0,2. In the horizontal plane the main lobe of the directional pattern at different frequencies is shifted by an angle of 5–10 deg relative to the normal to the radiating opening of the emitters. The reason is a microstrip distributor combined with printed antenna array emitters on a common printed circuit board. The specified offset of the main lobe of the directional pattern does not decrease the functional characteristics of the antenna device, because the difference in level in the direction of the main maximum and in the direction normal to the radiating aperture of antenna arrays does not exceed 0,5 dB. In addition, the specified offset at the given frequency is regular and has the same value for all emitters of the ring antenna array. Therefore, the angular discret and the level of overlap of the directional patterns of the neighboring emitters when scanning in the azimuthal plane remain unchanged. The results of an experimental study of a prototype antenna device have been presented. They are in good agreement with the results of computer modeling.

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Design of Concentric Ring Antenna Arrays Based on Subarrays to Simplify the Feeding System

Symmetry ◽

10.3390/sym12060970 ◽

2020 ◽

Vol 12 (6) ◽

pp. 970

Author(s):

Elizvan Juárez ◽

Marco A. Panduro ◽

Alberto Reyna ◽

David H. Covarrubias ◽

Aldo Mendez ◽

...

Keyword(s):

Antenna Arrays ◽

Side Lobe ◽

Phase Shifters ◽

Side Lobe Level ◽

Antenna Element ◽

Feeding System ◽

Concentric Ring ◽

Array Pattern ◽

Ring Antenna ◽

Symmetry Problem

The global synthesis for antenna arrays that produce a desired radiation pattern is a scientific symmetry problem. This paper deals with the design of concentric ring antenna arrays to simplify the feeding system using a cophasal subarray configuration. This simplification in the feeding network is achieved by the reduction of phase shifters via a proper clustering of radiators applying one amplitude and one phase excitation by subarray in the array system. The array design for this geometry considers an optimization process based in differential evolution to reduce the side-lobe level, resulting in simplification of the feeding network. Simulation results based on CST Microwave Studio and HFSS are provided to verify the accuracy of the array model and to take mutual coupling into account. These simulations are provided using a circular patch as antenna element to generate a scannable array pattern over the elevation plane. Furthermore, an analysis of the manufacturing tolerances was made to verify the reliability of our design.

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