scholarly journals AMPLITUDE-PHASE DISTRIBUTION MEASUREMENT PLANE DIMENSIONS INFLUENCE ON THE HOLOGRAPHIC METHOD ANTENNA ARRAY RADIATION PATTERN RECONSTRUCTION ERRORS

Doklady BGUIR ◽  
2020 ◽  
pp. 5-13
Author(s):  
O. A. Yurtsev ◽  
R. Ch. Shimanouski
Keyword(s):  
Antenna Array ◽  
Radiation Pattern ◽  
Phase Distribution ◽  
Near Field ◽  
Amplitude Distribution ◽  
Holographic Method ◽  
Longitudinal Zone ◽  
Measurement Plane ◽  
Measurement Surface ◽  
The Cost

The article explores the holographic method of measuring the antenna pattern. A flat antenna array is used as the antenna under test, and a planar rectangular surface is used as the surface on which the amplitudephase distribution in the near field is measured. Using the example of a flat antenna array, we consider the influence of the size of the measurement surface of the amplitude-phase distribution of the field in a plane orthogonal to the reconstruction plane of the radiation pattern. Antenna emitters are excited with a combined amplitude distribution and linear phase distribution. The field in the longitudinal zone of the lattice is determined using the Kirchhoff integral. The reconstructed radiation patterns are estimated using the amplitude-phase distribution over the entire measurement plane in comparison with the array radiation pattern in the far zone. A numerical analysis of the influence on the errors in determining the parameters of the lattice radiation pattern using the holographic method is also carried out: the number of columns of the amplitude-phase distribution on the measurement plane, the position of this plane in three coordinates relative to the plane of the aperture of the lattice. It is shown that if the spacing of the points of measurement of the amplitude-phase distribution and the pitch of the lattice are equal, to restore the radiation pattern using the holographic method, it is sufficient to use one column of the amplitude-phase distribution on the measurement plane. This greatly simplifies and reduces the cost of the measurement process and the necessary equipment. Examples of determining errors in measuring the parameters of the antenna array when shifting the plane of measurement of the amplitude-phase distribution in three coordinates are given.

SERIES FEED FAN-BEAM ANTENNA ARRAY WITH A LOW SIDELOBE LEVEL FOR POSITIONING SYSTEM

2020 ◽  
pp. 55-65
Author(s):  
Le Minh Thuy
Keyword(s):  
Antenna Array ◽  
Radiation Pattern ◽  
Amplitude Distribution ◽  
High Gain ◽  
Impedance Bandwidth ◽  
Antenna Element ◽  
Positioning System ◽  
Sidelobe Level ◽  
Single Antenna ◽  
Low Sidelobe

In this paper, a novel antenna array at 5GHz is presented with a low sidelobe level and wide impedance bandwidth for indoor positioning applications . The antenna array has the size of 450 ×57×0.8 mm3 with the high gain of 14.5dBi and the low SLL of -18 dB at 5GHz. The series feed using Unequal Split T-Junction is proposed with the Chebyshev-amplitude distribution to improve SLL. Besides the 1800 phase and amplitude distribution, by deploying driven elements above each single antenna element, the radiation pattern and the gain of the antenna aray are significantly improved.

scholarly journals Method of forming and scaling phased array expanded beams

2019 ◽  
pp. 19-29
Author(s):  
A. N. Gribanov ◽  
S. E. Gavrilova ◽  
O. V. Pavlovich ◽  
G. F. Moseychuk ◽  
A. N. Titov
Keyword(s):  
Antenna Array ◽  
Phased Array ◽  
Phase Distribution ◽  
Amplitude Distribution ◽  
Scaling Factor ◽  
Beam Shape ◽  
Diagram Method ◽  
Phase Synthesis ◽  
Scaling Properties ◽  
Phased Antenna Array

The paper focuses on the phase synthesis of one-dimensionally expanded phased array beams. In the study we used the fan partial diagram method. By this method and applying the known amplitude distribution in the aperture and the desired beam shape, we were able to unambiguously determine the desired phase distribution by means of simple calculations. The method is applicable for a phased antenna array and an active phased antenna array with linear and flat apertures. The study is the first to discuss the scaling properties of expanded beams, which allow one to obtain many synthesis options from only one option by multiplying the phase distribution by the scaling factor. Four important properties of scaling are formulated and proved, which must be taken into account when scaling. The paper gives the results of mathematical simulation and experimental measurements, proving the efficiency of the method

scholarly journals Validation of the radiation pattern of the VHF MST radar MAARSY by scattering off a sounding rocket's payload

2015 ◽  
Vol 13 ◽  
pp. 41-48 ◽  
Author(s):  
T. Renkwitz ◽  
C. Schult ◽  
R. Latteck ◽  
G. Stober
Keyword(s):  
Antenna Array ◽  
Radiation Pattern ◽  
Middle Atmosphere ◽  
Phase Distribution ◽  
Lower Thermosphere ◽  
Beam Width ◽  
Sounding Rocket ◽  
Flexible Beam ◽  
Phased Array Antenna ◽  
Pointing Accuracy

Abstract. The Middle Atmosphere Alomar Radar System (MAARSY) is a monostatic radar with an active phased array antenna designed for studies of phenomena in the mesosphere and lower thermosphere. Its design, in particular the flexible beam forming and steering capability, makes it a powerful instrument to perform observations with high angular and temporal resolution. For the configuration and analysis of experiments carried out with the radar it is essential to have knowledge of the actual radiation pattern. Therefore, during the time since the radar was put into operation various active and passive experiments have been performed to gain knowledge of the radiation pattern. With these experiments the beam pointing accuracy, the beam width and phase distribution of the antenna array were investigated. Here, the use of a sounding rocket and its payload as a radar target is described which was launched in the proximity of the radar. The analysis of these observations allows the detailed investigation of the two-way radiation pattern for different antenna array sizes and beam pointing positions.

scholarly journals Decoupling of Multifrequency Dipole Antenna Arrays for Microwave Imaging Applications

2010 ◽  
Vol 2010 ◽  
pp. 1-8 ◽  
Author(s):  
E. Saenz ◽  
K. Guven ◽  
E. Ozbay ◽  
I. Ederra ◽  
R. Gonzalo
Keyword(s):  
Antenna Array ◽  
Radiation Pattern ◽  
Antenna Arrays ◽  
Mutual Coupling ◽  
Near Field ◽  
Field Measurements ◽  
Dipole Antenna ◽  
Far Field ◽  
Radiated Power ◽  
Near Field Scanning

The mutual coupling between elements of a multifrequency dipole antenna array is experimentally investigated byS-parameter measurements and planar near-field scanning of the radiated field. A multifrequency array with six dipoles is analyzed. In order to reduce the coupling between dipoles, a planar metasurface is placed atop the array acting as superstrate. The mutual coupling of the antenna elements in the absence and presence of the superstrate is presented comparatively. Between 3 and 20 dB mutual coupling reduction is achieved when the superstrate is used. By scanning the field radiated by the antennas and far-field measurements of the radiation pattern, it is observed that the superstrate confines the radiated power, increases the boresight radiation, and reduces the endfire radiation.

scholarly journals DIAGNOSTICS OF HEADLIGHTS FROM NEAR AREA ON PLACE OF BASING

2020 ◽  
Vol 3 (61) ◽  
pp. 124-127
Author(s):  
O. Besova ◽  
V. Karlov ◽  
O. Lukashuk ◽  
I. Petryshenko
Keyword(s):  
Antenna Array ◽  
Phased Array ◽  
Phase Distribution ◽  
Near Field ◽  
Operating Time ◽  
Array Antenna ◽  
Phased Array Antenna ◽  
Phased Antenna Array ◽  
Near Zone ◽  
Microwave Diagnostics

Methods of microwave diagnostics of a phased array allow reconstructing the amplitude-phase distribution in the antenna and implement on this basis methods for adapting the lattice control to those found in the amplitude-phase distribution to defects. The methods of microwave diagnostics from the near zone described in the well-known literature are realizable only in anechoic chambers or on specially equipped training grounds. To solve the problems of adapting a phased antenna array to a technical state and increasing its operating time under extreme conditions, it is necessary to have methods of integrated microwave diagnostics of a phased antenna array at its location. The aim of the article is to develop a method for microwave diagnostics of a phased array antenna, implemented from the near zone of the antenna at its location, and eliminating the influence of echo signals (ES) on the diagnostic results. The article proposes a method for microwave diagnostics of a phased array antenna from the near field, which allows to exclude the influence on the accuracy of diagnostics of the echo signal present at the measuring site and errors in the positioning of the measuring probe. The proposed method will make it possible to implement microwave diagnostics of the antenna from the near field at its location. The results of microwave diagnostics are supposed to be used to implement various methods of adapting a phased array to a technical condition, significantly increasing its life

scholarly journals An investigation of side lobe suppression in integrated printed antenna structures with 3D reflectors

2017 ◽  
Vol 30 (3) ◽  
pp. 391-402
Author(s):  
Marija Milijic ◽  
Aleksandar Nesic ◽  
Bratislav Milovanovic
Keyword(s):  
Antenna Array ◽  
Radiation Pattern ◽  
Antenna Arrays ◽  
Amplitude Distribution ◽  
Side Lobe ◽  
Printed Antenna ◽  
Side Lobe Suppression

The paper discusses the problem of side lobe suppression in the radiation pattern of printed antenna arrays with different 3D reflector surfaces. The antenna array of eight symmetrical pentagonal dipoles with corner reflectors of various angles is examined. All investigated antenna arrays are fed by the same feeding network of impedance transformers enabling necessary amplitude distribution. Considering the different reflector surfaces, the influence of parasitic radiation from feeding network on side lobe suppression is studied to prevent the reception of unwanted noise and to increase a gain.

Printed Antenna Array with Flat-Top Radiation Pattern

Frequenz ◽  
2018 ◽  
Vol 72 (5-6) ◽  
pp. 173-180 ◽  
Author(s):  
Marija R. Milijić ◽  
Aleksandar D. Nešić ◽  
Bratislav D. Milovanović ◽  
Dušan A. Nešić
Keyword(s):  
Antenna Array ◽  
Radiation Pattern ◽  
Phase Distribution ◽  
Side Lobe ◽  
Printed Antenna ◽  
Fractional Bandwidth ◽  
Radiation Characteristics ◽  
Centre Frequency ◽  
Feed Network ◽  
Flat Top Beam

AbstractA printed antenna array consisting of 10 wideband symmetrical pentagonal dipoles is presented. The feed network of impedance transformers is employed to provide appropriate amplitude and phase distribution necessary to obtain flat top beam pattern. The measured results demonstrate excellent radiation characteristics including 38° flat gain region with maximum ripple of 3.5 dB at the centre frequency. Furthermore, the proposed antenna that is placed in corner reflector with angle of 60° has good gain (17 dBi) and side lobe suppression (18.9 dB). Although it is designed at the centre frequencyfc=12 GHz, it was shown to be capable of shaping a good flat top radiation pattern within a fractional bandwidth at least 6 % of centre frequency. Also, proposed antenna features cheap, simple and easy fabrication that makes it suitable for mass production.

scholarly journals A dielectric free near field phase transforming structure for wideband gain enhancement of antennas

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Foez Ahmed ◽  
Muhammad U. Afzal ◽  
Touseef Hayat ◽  
Karu P. Esselle ◽  
Dushmantha N. Thalakotuna
Keyword(s):  
Phase Transformation ◽  
Phase Distribution ◽  
Near Field ◽  
Phase Error ◽  
Resonant Cavity ◽  
Amplitude Distribution ◽  
Antenna System ◽  
Field Phase ◽  
Gain Enhancement ◽  
Large Bandwidth

AbstractThe gain of some aperture antennas can be significantly increased by making the antenna near-field phase distribution more uniform, using a phase-transformation structure. A novel dielectric-free phase transforming structure (DF-PTS) is presented in this paper for this purpose, and its ability to correct the aperture phase distribution of a resonant cavity antenna (RCA) over a much wider bandwidth is demonstrated. As opposed to printed multilayered metasurfaces, all the cells in crucial locations of the DF-PTS have a phase response that tracks the phase error of the RCA over a large bandwidth, and in addition have wideband transmission characteristics, resulting in a wideband antenna system. The new DF-PTS, made of three thin metal sheets each containing modified-eight-arm-asterisk-shaped slots, is significantly stronger than the previous DF-PTS, which requires thin and long metal interconnects between metal patches. The third advantage of the new DF-PTS is, all phase transformation cells in it are highly transparent, each with a transmission magnitude greater than − 1 dB at the design frequency, ensuring excellent phase correction with minimal effect on aperture amplitude distribution. With the DF-PTS, RCA gain increases to 20.1 dBi, which is significantly greater than its 10.7 dBi gain without the DF-PTS. The measured 10-dB return loss bandwidth and the 3-dB gain bandwidth of the RCA with DF-PTS are 46% and 12%, respectively.

Sign in / Sign up

Export Citation Format

Share Document