scholarly journals Dual Circularly Polarized Omnidirectional Antenna with Slot Array on Coaxial Cylinder

2015 ◽  
Vol 2015 ◽  
pp. 1-7 ◽  
Author(s):  
Bin Zhou ◽  
Junping Geng ◽  
Zhe Li ◽  
Wenzhi Wang ◽  
Xianling Liang ◽  
...  
Keyword(s):  
Return Loss ◽  
Axial Ratio ◽  
Coaxial Cylinder ◽  
Circularly Polarized ◽  
Left Hand ◽  
Omnidirectional Antenna ◽  
Right Hand ◽  
Two Sides

A dual circularly polarized (CP) omnidirectional antenna based on slot array in coaxial cylinder structure is presented in this paper. It is constructed by perpendicular slot pairs around and along the axis of the coaxial cylinder to realize the omnidirectional CP property, and two ports are assigned in its two sides as left hand circularly polarized (LHCP) port and right hand circularly polarized (RHCP) port, respectively. The proposed antenna achieves a bandwidth of 16.4% ranging from 5.05 to 5.95 GHz with an isolation higher than 15 dB between the two CP ports, and the return loss (RL) is higher than 10 dB within the bandwidth in both of the two ports. From the measured results, the average axial ratio (AR) of the proposed antenna in omnidirectional plane is lower than 1.5 dB.

scholarly journals A SYNCHRONOUS SUB-ARRAY CIRCULARLY POLARIZED MICROSTRIP ANTENNA FOR BISAR ONBOARD UAV

2018 ◽  
Author(s):  
Yohandri
Keyword(s):  
Circular Polarization ◽  
Microstrip Antenna ◽  
Axial Ratio ◽  
Array Antenna ◽  
Circularly Polarized ◽  
Left Hand ◽  
Right Hand ◽  
L Band

A circularly polarized microstrip antenna for bi-static SAR onboard UAV has been investigated. The both senseof the circular polarization left-hand circularly polarized (LHCP) and right-hand circularly polarized (RHCP) arecan be achieved on experimental and simulation. The 2x2 sub array antenna operated in 1.176 (L-band) withnovel proximity synchronous feed method has been designed, fabricated, and evaluated to show the characteristic of the antenna. The measured result give the axial ratio bandwidth (<3dB) of about 28 MHz (2%), whichconsistent with the simulated result of about 27 MHz (2%). These results satisfy the specification for our BiSARsystem installed onboard UAV.

scholarly journals Simple Reconfigurable Circularly Polarized Antenna at Three Bands

Sensors ◽  
2019 ◽  
Vol 19 (10) ◽  
pp. 2316 ◽  
Author(s):  
Tu Le ◽  
Han-Young Park ◽  
Tae-Yeoul Yun
Keyword(s):  
Axial Ratio ◽  
Loop Antenna ◽  
Impedance Bandwidth ◽  
Simple Design ◽  
Pin Diodes ◽  
Circularly Polarized ◽  
Left Hand ◽  
Fabrication Cost ◽  
Right Hand ◽  
Triple Band

In this paper, a simple design for a triple-band circularly polarized (CP) antenna with the capability of switching its polarization between dual-sense CPs is presented. The proposed antenna is comprised of a monopole loop antenna as a primary radiator. By placing a parasitic loop around the primary radiator, an additional CP band is achieved. Reconfigurability of the polarization between right-hand CP (RHCP) and left-hand CP (LHCP) at three different frequencies of 2.5, 3.3, and 3.8 GHz was realized by controlling the ON/OFF states of two PIN diodes. For validation, the fabricated antenna yielded an impedance bandwidth of 52.6% (2.34–4.01 GHz), while the axial ratio bandwidths for both the RHCP and LHCP states were 3.5% (2.47–2.56 GHz), 6.6% (3.20–3.42 GHz), and 2.4% (3.74–3.83 GHz). The measured broadside gains within the axial ratio bandwidth were 1.2, 2.7, and 1.4 dBi, respectively. Compared to other reconfigurable multi-band CP antennas, the proposed design is the first work to achieve a reconfigurable polarization at three distinct bands at a low fabrication cost by using only two diodes. The proposed antenna is suitable for WLAN and WiMAX applications.

Bilayer split-ring chiral metamaterial based reconfigurable antenna for polarization conversion

Frequenz ◽  
2021 ◽  
Vol 0 (0) ◽  
Author(s):  
Preet Kaur ◽  
Pravin R. Prajapati
Keyword(s):  
Low Cost ◽  
Axial Ratio ◽  
Center Frequency ◽  
Impedance Bandwidth ◽  
Split Ring ◽  
Circularly Polarized ◽  
Left Hand ◽  
Rectangular Patch ◽  
Mode 2 ◽  
Chiral Metamaterial

Abstract A bilayer split-ring chiral metamaterial converts the linearly polarized wave, into a nearly perfect left or right-handed circularly polarized wave. The proposed antenna is intended to operate at center frequency of 5.80 GHz with switchable polarization capability. The polarization re-configurability is achieved by electronically switching of two PIN-diode pairs, which are embedded into bilayer split-ring Chiral Metamaterial. The optimized length of rectangular patch is 16 mm and width is 12.1 mm. Two types of radiation characteristics offered by the proposed antenna; left hand circularly polarized in mode 1 and right hand circularly polarized in mode 2. Measured results show that its impedance bandwidth is 155 MHz from 5.70 to 5.855 GHz for both mode 1 and mode 2. The measured axial-ratio bandwidth is 100 MHz from 5.75 to 5.85 GHz for mode 1 and 110 MHz from 5.73 to 5.84 GHz for mode 2. Antenna has LHCP gain of 2.52 dBi and RHCP gain of −23 dBi in mode 1. RHCP gain of 2 dBi and polarization purity of about −20 dBi is obtained in mode 2. The proposed antenna has simple structure, low cost and it has potential application in field of wireless communication (i.e., WiMax, WLAN etc.).

Development and Miniaturized of Circularly Polarization Diversity at Cavity Backed SIW Antenna for X-Band Application

Frequenz ◽  
2019 ◽  
Vol 73 (9-10) ◽  
pp. 317-320
Author(s):  
Saeid Karamzadeh ◽  
Vahid Rafiei ◽  
Hasan Saygin
Keyword(s):  
Schottky Diodes ◽  
Axial Ratio ◽  
Impedance Bandwidth ◽  
Polarization Diversity ◽  
Circularly Polarized ◽  
Left Hand ◽  
Low Profile ◽  
X Band ◽  
Coaxial Feed ◽  
Good Agreement

Abstract In this work circularly polarization diversity has been achieved by utilizing two Schottky diodes on low profile cavity-backed substrate integrated waveguide (CBSIW). In comparison with other studies in the literature, the size of antenna has been reduced to 0.54λg × 0.76λg by helping a 50-Ohm coaxial feed line. The impedance bandwidth, axial ratio bandwidth and antenna gain are improved to 10.02 %, 5.2 % and 7.68dBi, respectively. In addition, the proposed antenna can generate either a left-hand circularly polarized (LHCP) or a right-hand circularly polarized (RHCP) radiation. The developed antenna was fabricated and tested and the achieved results were in good agreement with the simulated one.

Circularly Polarized Rectangular Microstrip Patch Antenna with Finite Ground Plane

2015 ◽  
Vol 4 (2) ◽  
pp. 74
Author(s):  
Sanyog Rawat ◽  
Kamlesh Kumar Sharma
Keyword(s):  
Patch Antenna ◽  
Return Loss ◽  
Ground Plane ◽  
Axial Ratio ◽  
Microstrip Patch Antenna ◽  
Simulation Software ◽  
Impedance Bandwidth ◽  
Circularly Polarized ◽  
Microstrip Patch ◽  
Rectangular Patch

<p class="Abstract"><span style="font-weight: normal;">In this paper a new geometry of patch antenna is proposed with improved bandwidth and circular polarization. The radiation performance of circularly polarized rectangular patch antenna is investigated by applying IE3D simulation software and its performance is compared with that of conventional rectangular patch antenna.</span> <span style="font-weight: normal;">Finite Ground truncation technique is used to obtain the desired results. The simulated return loss, axial ratio and smith chart with frequency for the proposed antenna is reported in this paper. It is shown that by selecting suitable ground-plane dimensions, air gap and location of the slits, the impedance bandwidth can be enhanced upto 10.15 % as compared to conventional rectangular patch (4.24%) with an axial ratio bandwidth of 4.05%.</span></p><p> </p><p> </p>

Right-Hand/Left-Hand Circularly Polarized High-Gain Antennas Using Partially Reflective Surfaces

2014 ◽  
Vol 13 ◽  
pp. 431-434 ◽  
Author(s):  
Avinash R. Vaidya ◽  
Rajiv K. Gupta ◽  
Sanjeev K. Mishra ◽  
Jayanta Mukherjee
Keyword(s):  
High Gain ◽  
Circularly Polarized ◽  
Left Hand ◽  
Right Hand ◽  
Reflective Surfaces

Analysis and Design of a Multi Octave Circularly Polarized Monopole Antenna for UWB, X and Ku-Band Applications

2018 ◽  
Vol 7 (3.4) ◽  
pp. 80
Author(s):  
Saritha Vanka ◽  
Tanmayi Seedrala ◽  
Jhansi Rani Areti
Keyword(s):  
Return Loss ◽  
Impedance Matching ◽  
Axial Ratio ◽  
Frequency Region ◽  
Monopole Antenna ◽  
Impedance Bandwidth ◽  
Good Correspondence ◽  
Circularly Polarized ◽  
Analysis And Design ◽  
Ku Band

This work presents a circularly polarized, CPW-Fed multi band operating monopole antenna. The monopole antenna consists of three parasitic elements, along with a stub at ground for impedance matching. The parasitic elements so far accumulated have shown their excellence in increasing the impedance bandwidth over the 6-18GHz band. The antenna was carved on FR-4 epoxy substrate which result a copper clad laminated structure. The CPW-Fed monopole antenna exhibits excellent circular polarization levels in the frequency region 6-18GHz. The simulation resulted a Return loss of less than -10dB, with good axial ratio less than -3dB over entire band of interest. The simulation was carried out through HFSS microwave studio. The antenna measured values are in good correspondence to the simulated values. 

Handwriting, Typewriting and Handedness

1968 ◽  
Vol 20 (3) ◽  
pp. 282-289 ◽  
Author(s):  
K. A. Provins ◽  
D. J. Glencross
Keyword(s):  
Performance Levels ◽  
Positive Correlation ◽  
Left Hand ◽  
Right Hand ◽  
Significant Difference ◽  
The Right ◽  
Two Sides

The performance of two groups of 20 trained touch typists and one group of 20 nontypists was tested on seven different typewriting exercises. Three of these exercises were executed entirely with the right hand and three were completed using only the left. A comparison of performances of the two sides showed, for the typists, no differences between the sides or a difference in favour of the left hand; and for the non-typists, a difference between hands in favour of the right side in two of the three comparisons. A comparison of handwriting performance with the preferred and non-preferred hands was carried out on 80 subjects. Apart from a highly significant difference in performance between the sides in favour of the preferred hand, this task showed, as did the typewriting task, a marked positive correlation between the performance levels of the two sides. These findings are briefly discussed in relation to the training histories of the subjects.

scholarly journals WAVEGUIDE FEED NETWORK FOR HORN ANTENNA WITH CIRCULAR POLARIZATION

2021 ◽  
Author(s):  
Stepan Piltyay
Keyword(s):  
Circular Polarization ◽  
Electromagnetic Waves ◽  
Metal Structure ◽  
Horn Antenna ◽  
Variable Cross ◽  
Circularly Polarized ◽  
Maximum Gain ◽  
Left Hand ◽  
Right Hand ◽  
Feed Network

The article presents the methodology for designing and optimizing of feed network for a circularly polarized horn antenna. A horn antenna has a metal structure and consists of a waveguide that has a variable cross-section and an open radiating end. Electromagnetic waves in such antenna are excited by a waveguide that is connected to a horn antenna in through the narrow wall. The proposed feed network of the horn antenna consists of a rectangular waveguide with a slot. In order to obtain the excitation of signals with circular polarization at the output, a slot was cut in the waveguide at an angle of 45º. As a result, the network makes it possible to form the signals with right-hand circular polarization and left-hand circular polarization. The presented design of the horn antenna feed network eliminates the need to develop a separate waveguide device of polarization processing. The designed feed network of the circularly polarized horn antenna can be used at an operating frequency of 8.0 GHz. At these frequency the reflection coefficient is less than −19 dB. The proposed horn antenna provides a maximum gain of 21 dB for right-hand circular polarization and a maximum gain of 10 dB for left-hand circular polarization. Cross-polarization isolation is higher than 10 dB. Therefore, the developed feed network of the horn antenna provides narrowband operating mode at the circular polarization with satisfying electromagnetic polarization characteristics and matching at the frequency of 8 GHz. Developed feed network of the horn antenna with circular polarization can be used in radio engineering systems, which carry out polarization processing of signals.

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