&lt;title&gt;New ultrawide-bandwidth horn-fed dipole GPR antenna design&lt;/title&gt;

Chen, Chi‐Chih; Higgins, Matthew B.

doi:10.1117/12.383503

Cited by 3 publications

(2 citation statements)

References 0 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…For frequencies higher than about 200 MHz, the TEM horn antenna (a flared stripline) has sometimes been used for higher efficiency and to provide a useful narrowing of the beam whilst allowing up to three octaves bandwidth free of dispersion. The combination of a horn, filled with dielectric similar in permittivity to the ground, or ice, and feeding a 'bow tie' dipole on the ground surface has been described by Chen and Higgins (2000) and shown to have an input reflection coefficient < − 10 dB from 20 to 800 MHz.…”

Section: Temperate Glaciersmentioning

confidence: 99%

Investigations of the form and flow of ice sheets and glaciers using radio-echo sounding

2004

View full text Add to dashboard Cite

Radio-echo sounding (RES), utilizing a variety of radio frequencies, was developed to allow glaciologists to measure the thickness of ice sheets and glaciers. We review the nature of electromagnetic wave propagation in ice and snow, including the permittivity of ice, signal attenuation and volume scattering, along with reflection from rough and specular surfaces. The variety of instruments used in RES of polar ice sheets and temperate glaciers is discussed. The applications and insights that a knowledge of ice thickness, and the wider nature of the form and flow of ice sheets, provides are also considered. The thickest ice measured is 4.7 km in East Antarctica. The morphology of the Antarctic and Greenland ice sheets, and many of the smaller ice caps and glaciers of the polar regions, has been investigated using RES. These findings are being used in three-dimensional numerical models of the response of the cryosphere to environmental change. In addition, the distribution and character of internal and basal reflectors within ice sheets contains information on, for example, ice-sheet layering and its chrono-stratigraphic significance, and has enabled the discovery and investigation of large lakes beneath the Antarctic Ice Sheet. Today, RES from ground-based and airborne platforms remains the most effective tool for measuring ice thickness and internal character.

show abstract

Section: Temperate Glaciersmentioning

confidence: 99%

Investigations of the form and flow of ice sheets and glaciers using radio-echo sounding

2004

View full text Add to dashboard Cite

show abstract

“…Conventional antenna modeling often employs Commercial Computational Electromagnetics (CEM) software such as FEKO, HFSS, ADS, IE3D, and CST for obtaining solutions to partial differential equations under specified boundary conditions through computer-based methods. These software tools are extensively utilized for antenna design, applying Maxwell's equations to simulate the interaction between electromagnetic fields and antennas [32]. While widely applied in antenna simulation and testing [33], numerical analysis approaches like Methods of Moments (MoM), Finite Element Method (FEM), and Finite Difference Time Domain (FDTD) exhibit commonality.…”

Section: Machine Learning (Ml) Based Optimizationmentioning

confidence: 99%

Machine Learning-Optimized Compact Frequency Reconfigurable Antenna With RSSI Enhancement for Long-Range Applications

Yahya,

Soeung,

Rahim

et al. 2024

IEEE Access

View full text Add to dashboard Cite

This study presents an innovative and compact monopole antenna with dual-band frequency reconfigurability for LoRa applications. It operates within the 915 MHz and 868 MHz frequencies, aligning with the designated bands for use in America, Asia and Europe. No existing compact reconfigurable antenna with these features for LoRa applications within ISM bands below 1 GHz is known. Employing an economical FR-4 substrate in its design, the antenna attains a compact size of 40 × 42 mm 2 (0.12 λ 0 × 0.12 λ 0 ), where λ 0 denotes the wavelength in free space corresponding to 868 MHz. A single RF PIN diode enables seamless switching between 868 MHz and 915 MHz bands. Design, simulation, and optimization employed CST MWS ® software. Supervised regression Machine Learning (ML) models predicted resonance frequencies, with Gaussian Process Regression emerging as optimal, achieving Rsquared and variance scores of 92.87% and 93.77%, respectively. A maximum gain of 2 dBi at 915 MHz and 70% efficiency, boasting good radiation patterns and matching was demonstrated by the antenna. Experimental validation in a football field at Universiti Teknologi PETRONAS, Malaysia, assessed the proposed antenna's performance on a LoRa transceiver system based on LoRa SX1276. The Received Signal Strength Indicator (RSSI) of the proposed antenna consistently exceeded the conventional commercially available monopole antenna by an average of −12 dBm at every point up to 300 m, showcasing enhanced signal reception. The antenna proves promising for wireless sensor nodes in long-range applications.INDEX TERMS Dual-band, LoRa, PIN-diode, reconfigurable, RSSI.

show abstract

Application of Alford rotation to ground-penetrating radar data

Gestel

Stoffa

2001

GEOPHYSICS

View full text Add to dashboard Cite

We investigate the application of Alford rotation to ground‐penetrating radar (GPR) data. By recording the reflected field amplitudes using four different configurations, we extract information about the orientation of buried objects that have angle‐dependent reflectivity. In theory this method can be successfully applied to find the orientation of dipping layers, cylinders, and vertical fractures. Modeling results show angle‐dependent reflections in all three cases; as a result, we can exactly determine the orientation of these targets. Analysis of a field survey at a controlled GPR test site in which reflections were collected from an elongate cylinder buried in a homogeneous soil show good prediction of the angle of orientation of the cylinder and confirm the expected theoretical and modeling results. The Alford rotation method requires accurate data acquisition for effective practical implementation. Improved results will require exact knowledge of the radiation pattern of the GPR antennas under different circumstances.

show abstract

<title>New ultrawide-bandwidth horn-fed dipole GPR antenna design</title>

Cited by 3 publications

References 0 publications

Investigations of the form and flow of ice sheets and glaciers using radio-echo sounding

Investigations of the form and flow of ice sheets and glaciers using radio-echo sounding

Machine Learning-Optimized Compact Frequency Reconfigurable Antenna With RSSI Enhancement for Long-Range Applications

Application of Alford rotation to ground-penetrating radar data

Contact Info

Product

Resources

About