scholarly journals Octave-Band Four-Beam Antenna Arrays with Stable Beam Direction Fed by Broadband 4 × 4 Butler Matrix

Electronics ◽  
2021 ◽  
Vol 10 (21) ◽  
pp. 2712
Author(s):  
Andrzej Dudek ◽  
Piotr Kanios ◽  
Kamil Staszek ◽  
Slawomir Gruszczynski ◽  
Krzysztof Wincza
Keyword(s):  
Antenna Arrays ◽  
Octave Band ◽  
Radiation Patterns ◽  
Frequency Range ◽  
Beam Direction ◽  
Butler Matrix ◽  
Directional Filters ◽  
Signal Switching ◽  
Novel Concept ◽  
Theoretical Analyses

A novel concept of four-beam antenna arrays operating in a one-octave frequency range that allows stable beam directions and beamwidths to be achieved is proposed. As shown, such radiation patterns can be obtained when radiating elements are appropriately spaced and fed by a broadband 4 × 4 Butler matrix with directional filters connected to its outputs. In this solution, broadband radiating elements are arranged in such a way that, for the lower and upper frequencies, two separate subarrays can be distinguished, each one consisting of identically arranged radiating elements. The subarrays are fed by a broadband Butler matrix at the output to which an appropriate feeding network based on directional filters is connected. These filters ensure smooth signal switching across the operational bandwidth between elements utilized at lower and higher frequency bands. Therefore, as shown, it is possible to control both beamwidths and beam directions of the resulting multi-beam antenna arrays. Moreover, two different concepts of the feeding network connected in between the Butler matrix and radiating elements for lowering the sidelobes are discussed. The theoretical analyses of the proposed antenna arrays are shown and confirmed by measurements of the developed two-antenna arrays consisting of eight and twelve radiating elements, operating in a 2–4 GHz frequency range.

scholarly journals Diffuse Sound Absorptive Properties of Parallel-Arranged Perforated Plates with Extended Tubes and Porous Materials

Materials ◽  
2020 ◽  
Vol 13 (5) ◽  
pp. 1091 ◽  
Author(s):  
Dengke Li ◽  
Daoqing Chang ◽  
Bilong Liu
Keyword(s):  
Boundary Condition ◽  
Porous Material ◽  
Porous Materials ◽  
Sound Absorption ◽  
Azimuthal Angle ◽  
Octave Band ◽  
Frequency Range ◽  
Absorption Coefficients ◽  
Perforated Plates ◽  
Absorption Performance

The diffuse sound absorption was investigated theoretically and experimentally for a periodically arranged sound absorber composed of perforated plates with extended tubes (PPETs) and porous materials. The calculation formulae related to the boundary condition are derived for the periodic absorbers, and then the equations are solved numerically. The influences of the incidence and azimuthal angle, and the period of absorber arrangement are investigated on the sound absorption. The sound-absorption coefficients are tested in a standard reverberation room for a periodic absorber composed of units of three parallel-arranged PPETs and porous material. The measured 1/3-octave band sound-absorption coefficients agree well with the theoretical prediction. Both theoretical and measured results suggest that the periodic PPET absorbers have good sound-absorption performance in the low- to mid-frequency range in diffuse field.

STUDY OF PHASED ARRAYS OF SLOTTED WAVEGUIDE ANTENNAS WITH DIELECTRIC FILLING

2021 ◽  
pp. 42-47
Author(s):  
A. O. Pelevin ◽  
A. M. Lerer ◽  
G. F. Zargano
Keyword(s):  
Computer Simulation ◽  
Antenna Arrays ◽  
Dielectric Layer ◽  
Phased Arrays ◽  
Frequency Range ◽  
Phased Antenna Arrays ◽  
Operating Frequency Range ◽  
Slotted Waveguide ◽  
Dielectric Filling ◽  
Thin Dielectric Layer

The article describes the computer simulation of phased antenna arrays consisting of slotted waveguide antennas with air and dielectric filling. It is shown that inser-tion of a thin dielectric layer shifts the operating frequency range of phased anten-na arrays by 1 GHz or more down in frequency while maintaining directional char-acteristics.

A Broadband $3\times4$ Butler Matrix and its Application in Multibeam Antenna Arrays

2019 ◽  
Vol 67 (12) ◽  
pp. 7622-7627
Author(s):  
Kai-Ran Xiang ◽  
Fu-Chang Chen ◽  
Qing-Xin Chu ◽  
Michael J. Lancaster
Keyword(s):  
Antenna Arrays ◽  
Multibeam Antenna ◽  
Butler Matrix

scholarly journals Design and Development of a Wideband Planar Yagi Antenna Using Tightly Coupled Directive Element

Micromachines ◽  
2020 ◽  
Vol 11 (11) ◽  
pp. 975
Author(s):  
Muhammad A. Ashraf ◽  
Khalid Jamil ◽  
Ahmed Telba ◽  
Mohammed A. Alzabidi ◽  
Abdel Razik Sebak
Keyword(s):  
Reflection Coefficient ◽  
Wireless Communication ◽  
Radiation Pattern ◽  
Excellent Agreement ◽  
Frequency Range ◽  
Fractional Bandwidth ◽  
Yagi Antenna ◽  
Tightly Coupled ◽  
Simulation Results ◽  
Novel Concept

In this paper, a novel concept on the design of a broadband printed Yagi antenna for S-band wireless communication applications is presented. The proposed antenna exhibits a wide bandwidth (more than 48% fractional bandwidth) operating in the frequency range 2.6 GHz–4.3 GHz. This is achieved by employing an elliptically shaped coupled-directive element, which is wider compared with other elements. Compared with the conventional printed Yagi design, the tightly coupled directive element is placed very close (0.019λ to 0.0299λ) to the microstrip-fed dipole arms. The gain performance is enhanced by placing four additional elliptically shaped directive elements towards the electromagnetic field’s direction of propagation. The overall size of the proposed antenna is 60 mm × 140 mm × 1.6 mm. The proposed antenna is fabricated and its characteristics, such as reflection coefficient, radiation pattern, and gain, are compared with simulation results. Excellent agreement between measured and simulation results is observed.

scholarly journals A Compact UWB Antenna with a Quarter-Wavelength Strip in a Rectangular Slot for 5.5 GHz Band Notch

2013 ◽  
Vol 2013 ◽  
pp. 1-9 ◽  
Author(s):  
Pichet Moeikham ◽  
Chatree Mahatthanajatuphat ◽  
Prayoot Akkaraekthalin
Keyword(s):  
Frequency Band ◽  
Communication Systems ◽  
Notch Filter ◽  
Radiation Patterns ◽  
Frequency Range ◽  
Uwb Antenna ◽  
Antenna Structure ◽  
Rectangular Slot ◽  
Quarter Wavelength ◽  
Uwb Applications

The limitation of the electromagnetic interferences (EMIs) caused by UWB radiating sources into WLAN/WiMAX communication systems operating in the frequency band located around 5.5 GHz requires the adoption of appropriate design features. To this purpose, a notch filter integrated into an UWB antenna, which is able to ensure a better electrical insulation between the two mentioned communication systems with respect to that already presented by the authors Moeikham et al. (2011), is proposed in this paper. The proposed filter, consisting in a rectangular slot including a quarter-wavelength strip integrated on the lower inner edge of the UWB radiating patch, is capable of reducing the energy emission in the frequency range between 5.1 and 5.75 GHz resulting in lower EMIs with sensible electronic equipments working in this frequency band. The antenna structure has no need to be tuned after inserting the rectangle slot with a quarter-wavelength strip. The proposed antenna has potential to minimize the EMIs at a frequency range from 5.1 to 5.75 GHz. The radiation patterns are given nearly omnidirectional in plane and likely bidirectional in plane at all frequencies by the proposed antenna. Therefore, this antenna is suitable to apply for various UWB applications.

scholarly journals Principle for the Realization of Dual-Orthogonal Linearly Polarized Antennas for UWB Technique

2011 ◽  
Vol 2011 ◽  
pp. 1-11 ◽  
Author(s):  
Grzegorz Adamiuk ◽  
Mario Pauli ◽  
Thomas Zwick
Keyword(s):  
Substrate Surface ◽  
Single Point ◽  
Broad Band ◽  
Main Beam ◽  
Cross Polarization ◽  
Frequency Range ◽  
Beam Direction ◽  
Array Configuration ◽  
Uwb Radar ◽  
Linearly Polarized

A concept of an array configuration for an ultrawideband suppression of the cross-polarization is presented. The method is explained in detail, and a mathematical description of the principle is given. It is shown that the presented configuration is convenient for the development of very broad band, dual-orthogonal, linearly polarized antennas with high polarization purity. The investigated configuration shows a high decoupling of the orthogonal ports and is capable for antennas with a main beam direction perpendicular to the substrate surface, that is, for a planar design. The phase center of the antenna configuration remains fixed at one single point over the complete desired frequency range, allowing a minimum dispersion of the radiated signal. The influence of nonidealities in the feeding network on the polarization purity is investigated. The presented method introduces a superior possibility of an extension of typical UWB technique to fully polarized systems, which improves significantly performance in, for example, UWB-MIMO or UWB-Radar.

Sign in / Sign up

Export Citation Format

Share Document