EFFECT OF RADAR SENSITIVITY ON METEOR ECHO DURATIONS

1953 ◽  
Vol 31 (5) ◽  
pp. 758-767 ◽  
Author(s):  
D. W. R. McKinley
Keyword(s):  
Dipole Antenna ◽  
System Sensitivity ◽  
System Parameters ◽  
Radar Systems ◽  
Half Wave ◽  
Sensitivity Ratio ◽  
Experimental Relation

Meteor echo durations were observed simultaneously with two radar systems having a power sensitivity ratio of 33 db. An experimental relation between echo duration and system sensitivity is obtained which shows that the duration of meteor echoes varies slowly, but significantly, with system parameters. Curves are furnished to correct observed durations to zenithal durations, applicable to any system using a horizontal half-wave dipole antenna.

scholarly journals Design of Broadband Compact Canonical Triple-Sleeve Antenna Operating in UHF Band

2021 ◽  
Vol 21 (4) ◽  
pp. 291-298
Author(s):  
Chandana SaiRam ◽  
Damera Vakula ◽  
Mada Chakravarthy
Keyword(s):  
Wireless Communication ◽  
Instantaneous Frequency ◽  
Dipole Antenna ◽  
Frequency Range ◽  
Broadband Antenna ◽  
Operating Frequency Range ◽  
Half Wave ◽  
Measurement Results ◽  
Antenna Configuration ◽  
Good Agreement

In this paper, a novel compact broadband antenna at UHF frequencies is presented with canonical shapes. Hemispherical, conical and cylindrical shapes have all been considered for antenna configuration. The designed antenna provides an instantaneous frequency range from 370 to 5,000 MHz with omnidirectional characteristics. The antenna was simulated in CST Microwave Studio, fabricated and evaluated; the results are presented. The simulated and measurement results are in good agreement. The antenna has voltage standing wave ratio (VSWR) ≤ 1.9:1 in 400–570 MHz, 2,530–3,740 MHz and 4,180–4,620 MHz; it has VSWR ≤ 3:1 over the operating frequency range 370–5,000 MHz and the measured gain varies from -0.6 to 4.5 dBi over the frequency band. The concept of canonical-shaped antenna elements and the incorporation of triple sleeves resulted in a reduction of the length of the antenna by 62% compared to the length of a half-wave dipole antenna designed at the lowest frequency. The antenna can be used for trans-receiving applications in wireless communication.

scholarly journals Simple Half-Wave Dipole Antenna Analysis for Wireless Applications by CST Microwave Studio

2014 ◽  
Vol 94 (7) ◽  
pp. 21-23 ◽  
Author(s):  
Mohammad Tareq ◽  
Dewan Ashraful Alam ◽  
Mazidul Islam ◽  
Razin Ahmed
Keyword(s):  
Dipole Antenna ◽  
Wireless Applications ◽  
Half Wave ◽  
Cst Microwave Studio

scholarly journals Determination of Optimum Frequency for Electromagnetic-Assisted Nanofluid Core Flooding

2019 ◽  
Vol 9 (21) ◽  
pp. 4608 ◽  
Author(s):  
Wahaab ◽  
Yahya ◽  
Shafie ◽  
Soleimani ◽  
Rostami ◽  
...  
Keyword(s):  
Dipole Antenna ◽  
Reservoir Rock ◽  
Electromagnetic Properties ◽  
Core Flooding ◽  
The Finite Element Method ◽  
Optimum Frequency ◽  
Half Wave ◽  
Propagation Pattern ◽  
Dual Resonance

The coupling of electromagnetic (EM) wave to nanoflooding experiments, termed EM-assisted nanoflooding has gained enormous attention in recent years. This brings about the consideration of transmitter efficiency and the propagation pattern of the ensuing EM wave, both of which depend on reservoir electromagnetic properties. However, this has not been considered in previous works, despite its potential to improve the efficiency of the process through energy maximization. Hence, this study considers the effects of reservoir EM properties on the operation of a transmitter. The EM properties of saturated reservoir rock samples were measured. Afterward, a half-wave dipole antenna was modeled in a cylindrical reservoir based on the measured EM properties. The EM propagation pattern of the antenna was simulated in a frequency range of 100 MHz—2.0 GHz using the finite element method. The antenna was found to display dual resonance (at 800 MHz and 1.3 GHz) for sandstone saturated with oil, brine and nanofluid. Application of the EM wave at resonance frequency can help increase the efficiency of EM-assisted nanoflooding.

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