scholarly journals Design of Dual Circularly Polarised 2–15 GHz Feed and the Polarisation Degree Measurement for CSRH-II Antenna System

2015 ◽  
Vol 32 ◽  
Author(s):  
Sha Li ◽  
Yi Hua Yan ◽  
Zhi Jun Chen ◽  
Wei Wang ◽  
Fu Shun Zhang
Keyword(s):  
Standing Wave ◽  
Axial Ratio ◽  
Wide Band ◽  
Beam Width ◽  
Antenna System ◽  
Ultra Wide Band ◽  
The Sun ◽  
Fixed Phase ◽  
The Relationship ◽  
The Waves

AbstractThe Chinese Spectral Radioheliograph is an aperture-synthesis telescope observing the Sun in ultra wide bandwidth on the ground. It contains two arrays Chinese Spectral Radioheliograph-I and Chinese Spectral Radioheliograph-II from 0.4 to 15 GHz. In order to obtain ultra wide-band performance, the cascaded folded dipoles are used in this feed. At the same time, in order to get circularly polarised signals coming from the Sun, a wide-band 90° hybrid is added in the output ports of the feed. This feed has characteristics of about 10 dBi gain, less than 1.5 voltage standing wave ratio. It also has characteristics with low axial ratio, fixed phase centre location, and constant beam width in operating frequencies. Through cross-correlating all combinations of two orthogonal polarisations at each antenna, the polarisation state of the waves is measured and give a differential instrumental delay between two data channels. The relationship between the own polarisation degree of the Sun and the observed polarisation degree is also measured for cross-polarised delay in observing the Sun in this paper.

scholarly journals A New Impedance Matching Method for an Ultra-Wide Band and Dual Circularly Polarised Feed

2016 ◽  
Vol 33 ◽  
Author(s):  
Sha Li ◽  
Yi Hua Yan ◽  
Wei Wang ◽  
Zhi Jun Chen ◽  
Dong Hao Liu ◽  
...  
Keyword(s):  
High Frequency ◽  
Near Field ◽  
Impedance Matching ◽  
Axial Ratio ◽  
Wide Band ◽  
Beam Width ◽  
Metal Ring ◽  
Field Radiation ◽  
Fixed Phase ◽  
Strip Lines

AbstractIn traditional antenna design, metal components are not placed in the central part of the antenna as they change the characteristics of near field radiation. However, we show that placing a metal ring in the centre of the strip lines, which connect the ends of folded high-frequency dipoles, does not damage the performance of the feed. Instead it significantly improves the voltage standing wave ratio of the feed whilst other performance indicators are not compromised. Thus, our findings show an excellent way of improving the wide band feed. Based on this foundation, a new circularly polarised feed for operation between 0.4 to 2 GHz is introduced for the Chinese Spectral Radioheliograph in this paper. The issue of a feed impedance matching network is investigated. By optimising the impedance matching, the performance of the feed is enhanced with respect to the previous realisations of the Eleven feed. The simulation and experimental results show that the gain of the feed is about 10 dBi, and the VSWR is less than 2:1. In addition, the feed has a low axial ratio, fixed phase centre location, and constant beam width in the range of 0.4 to 2 GHz.

scholarly journals Efficient Microstrip Antenna system using Reduced GP Structure for Ultra-Wide Band (UWB) Applications

YMER Digital ◽  
2021 ◽  
Vol 20 (12) ◽  
pp. 790-807
Author(s):  
N Parthiban ◽  
◽  
M Mohamed Ismail ◽  
Keyword(s):  
Frequency Band ◽  
Antenna Arrays ◽  
Patch Antenna ◽  
Microstrip Antenna ◽  
Wide Band ◽  
Antenna System ◽  
Microstrip Patch Antenna ◽  
Ultra Wide Band ◽  
Microstrip Patch ◽  
Uwb Applications

Microstrip antenna is an essential choice for Ultra Wide Band (UWB) applications of its light weight, low profile and easy to form antenna arrays. However, the design of microstrip patch antenna bandwidth is greatly affects by the dielectric substrate material (FR4). In this research, the bandwidth enhancement of MPA was designed by minimizing the dimension of Defected GP (DGP) in GP for Ultra Wide Band wireless applications. But, the antenna design complexity increases with the number of an operating frequency band. In this research, the MPA was designed as small as size of 10×13×1.6 mm and operates on frequency band between 3.1GHz to 10.6GHz for VSWR less than 2. The microstrip patch antenna was designed at 3.1GHz to 10.6GHz using High-Frequency Structure Simulator (HFSS) software. The simulation result shows that the proposed microstrip patch antenna obtained <-10dB of return loss from 3.1GHz to 10.6GHz throughout the frequency range. The measured result proves that the proposed microstrip patch antenna has better characteristics to fulfill the requirements of UWB applications

scholarly journals An Ultra-Wide Band Antenna System for Pulsed Sources Direction Finding

Sensors ◽  
2020 ◽  
Vol 20 (17) ◽  
pp. 4695
Author(s):  
Razvan D. Tamas ◽  
Stefania Bucuci
Keyword(s):  
Power Distribution ◽  
Distribution Systems ◽  
Wide Band ◽  
Direction Finding ◽  
Antenna System ◽  
Ultra Wide Band ◽  
Electric Discharges ◽  
Power Distribution Systems ◽  
Short Pulses ◽  
Electromagnetic Signature

Electric discharges in high-voltage power distribution systems can be localized through their electromagnetic signature in the radio-frequency range. Since discharges produce series of short pulses, the corresponding spectrum usually covers wide frequency ranges, typically up to 1 GHz. In this paper, we propose an ultra-wide band (UWB) antenna system and a direction-finding (DF) approach based on using energy-based descriptors, instead of classical frequency-domain parameters. As an antenna system, we propose a dual-padlock configuration with a suitable pulse-matched response, featuring two unbalanced outputs. The proposed antenna system was successfully validated, both by simulations and measurements.

Diversity performance analysis of four port triangular slot MIMO antenna for WiBro and ultrawide band (UWB) applications

Frequenz ◽  
2021 ◽  
Vol 0 (0) ◽  
Author(s):  
Praveen Vummadisetty Naidu ◽  
Sai haranadh Akkapanthula ◽  
Maheshbabu Dhanekula ◽  
Neelima Vummadisetty ◽  
Arvind Kumar
Keyword(s):  
Mutual Coupling ◽  
Group Delay ◽  
Mimo System ◽  
Wide Band ◽  
Cost Effective ◽  
Antenna System ◽  
Ultra Wide Band ◽  
Mimo Antenna ◽  
Capacity Loss ◽  
Uwb Applications

Abstract This article discusses a 4-port micro-strip fed MIMO Antenna system with a triangular slot and an inverted L shape strip has been designed and analysed for both 2.3 GHz WiBro and Ultra-wide-band applications. The suggested antenna has been etched on a cost-effective epoxy (FR-4) substrate having ϵ r ${{\epsilon}}_{r}$  = 4.4 with an overall dimension of 45 × 45 × 1.6 mm3. Mutual coupling of −18 dB between the radiators has been obtained by orthogonal placement of radiators. From the simulated and practical results, the proposed compact MIMO system operates in frequency bands 2.26–2.42 GHz and 3.7–10.8 GHz respectively. The proposed small triangular MIMO system operates with an ECC less than 0.005 with an acceptable channel capacity loss <0.5 bits/s/Hz. Further, the diversity characteristics like DG, MEG, TARC, and group delay have been calculated and are presented in this paper.

scholarly journals Compact Ultra-Wide Band MIMO Antenna System for Lower 5G Bands

2018 ◽  
Vol 2018 ◽  
pp. 1-6 ◽  
Author(s):  
Haitham AL-Saif ◽  
Muhammad Usman ◽  
Muhammad Tajammal Chughtai ◽  
Jamal Nasir
Keyword(s):  
Mutual Coupling ◽  
Return Loss ◽  
Wide Band ◽  
Antenna System ◽  
Ultra Wide Band ◽  
Center Frequency ◽  
Mimo Antenna ◽  
Total Structure ◽  
Good Agreement ◽  
Array Geometry

This paper presents a novel compact 2 × 2 planar MIMO antenna system with ultra-wide band capability. Antenna system is specifically designed to target lower 5th generation operating bands ranging from 2 GHz to 12 GHz. This band also covers the IEEE 802.11 a/b/g/n/ac. The antenna array geometry has been simulated using CST MWS. The design is extremely miniaturized with total structure size of 13×25×0.254 mm3. The simulated and measured results have been presented. Measured and simulated return loss values for designed antenna are less than −10 dB over the operating band and lowest values of −35 dB and −32.5 dB can been seen at 5.2 GHz and 9.2 GHz, respectively, whereas at the center frequency the return loss is −25.2 dB. The mutual coupling between both elements is less than −20 dB over the transmission bandwidth. Simulated and measured radiation patterns in E and H planes at center frequency show nearly isotropic far fields. The maximum gain is measured as 4.8 dB. Promising results of Envelope Correlation Coefficient and gain diversity of the design have been achieved. Simulated and measured results are found in good agreement. The fractional bandwidth of antenna is measured as 143.2% which satisfies its ultra-wide band response.

scholarly journals A Wide Beam Printed Quadrifilar Helix based Circularly Polarised Radiating Element for Electronically Steered Antenna

2021 ◽  
Vol 71 (1) ◽  
pp. 66-70
Author(s):  
Raj Kumar ◽  
Pramendra Kumar Verma ◽  
M.V. Kartikeyan
Keyword(s):  
Beam Steering ◽  
Axial Ratio ◽  
Wide Band ◽  
Beam Width ◽  
Impedance Bandwidth ◽  
Band Frequency ◽  
Wide Beam ◽  
Radiating Element ◽  
Structure Simulation ◽  
Half Power

Wide beam and low axial ratio performance of printed quadrifilar antennas result in very attractive circularly polarised radiating element for wide scanned Electronically Steered Antenna. A compact printed quadrifilar Helix antenna (PQHA) has been designed and realised at S-Band frequency. Simulation and optimisation of designed antenna has been performed using ANSYS’s high frequency structure simulation (HFSS) software for its impedance, axial ratio (AR) performance and radiation characteristics. The developed circularly polarised antenna has 3-dB beam width of 130° and peak gain of 3.4dBic at 2.6 GHz. The developed antenna shows excellent AR performance over the frequency band as well as over the radiated beam. Half power axial ratio bandwidth of developed antenna is 27.4% (2.2 GHz - 2.9 GHz) while the impedance bandwidth is 32% (2.1 GHz - 2.9 GHz). Design has been validated through measured results. Designed wide band PQHA can be used as radiating element for electronically steered antenna for large beam steering application.

scholarly journals Efficient Microstrip Antenna system using Reduced GP Structure for Ultra-Wide Band (UWB) Applications

2021 ◽  
Author(s):  
Parthiban N ◽  
Mohamed Ismail M
Keyword(s):  
Frequency Band ◽  
Antenna Arrays ◽  
Patch Antenna ◽  
Microstrip Antenna ◽  
Wide Band ◽  
Antenna System ◽  
Microstrip Patch Antenna ◽  
Ultra Wide Band ◽  
Microstrip Patch ◽  
Uwb Applications

Abstract Microstrip antenna is an essential choice for Ultra Wide Band (UWB) applications of its light weight, low profile and easy to form antenna arrays. However, the design of microstrip patch antenna bandwidth is greatly affects by the dielectric substrate material (FR4). In this research, the bandwidth enhancement of MPA was designed by minimizing the dimension of Defected GP (DGP) in GP for Ultra Wide Band wireless applications. But, the antenna design complexity increases with the number of an operating frequency band. In this research, the MPA was designed as small as size of 10×13×1.6 mm and operates on frequency band between 3.1GHz to 10.6GHz for VSWR less than 2. The microstrip patch antenna was designed at 3.1GHz to 10.6GHz using High-Frequency Structure Simulator (HFSS) software. The simulation result shows that the proposed microstrip patch antenna obtained <-10dB of return loss from 3.1GHz to 10.6GHz throughout the frequency range. The measured result proves that the proposed microstrip patch antenna has better characteristics to fulfill the requirements of UWB applications.

Activity Recognition using Ultra Wide Band Range-Time Scan

2021 ◽  
Author(s):  
Arijit Chowdhury ◽  
Taniya Das ◽  
Smriti Rani ◽  
Anwesha Khasnobish ◽  
Tapas Chakravarty
Keyword(s):  
Activity Recognition ◽  
Wide Band ◽  
Ultra Wide Band ◽  
Time Scan
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