Radar Signal Propagation and Detection Through Ice

2010 ◽  
pp. 247-269
Author(s):  
Wlodek Kofman ◽  
Roberto Orosei ◽  
Elena Pettinelli
Keyword(s):  
Signal Propagation ◽  
Radar Signal

Radar signal propagation through the ionosphere of Europa

2015 ◽  
Vol 117 ◽  
pp. 421-428 ◽  
Author(s):  
Cyril Grima ◽  
Donald D. Blankenship ◽  
Dustin M. Schroeder
Keyword(s):  
Signal Propagation ◽  
Radar Signal

Determining Bridge Deck Chloride Quantities Using Ground Penetrating Radar

2021 ◽  
Author(s):  
Anthony Alongi
Keyword(s):  
Ground Penetrating Radar ◽  
Bridge Deck ◽  
Bridge Decks ◽  
Cost Effective ◽  
Chloride Content ◽  
Signal Propagation ◽  
Radar Signal ◽  
Signal Loss ◽  
Deicing Salts ◽  
Ground Penetrating

<p>Chlorides from deicing salts attack the steel reinforcement in bridge decks which can ultimately cause delamination and deterioration of the concrete. For transportation agencies, the repair cost from these defects are estimated to exceed $5B per year in USA and make up between 50% - 85% of bridge maintenance budgets. While, the removal and replacement of chloride contaminated concrete is the most long-lasting and cost-effective remediation, few methods exist to determine chloride content in bridge decks. This research describes an entirely new method for determining chloride quantity in bridge decks using ground penetrating radar (GPR) technology and establishes and quantifies the relationship between chlorides in concrete (which cause corrosion of reinforcing steel and delamination of concrete) and the effect on GPR signal propagation. Specifically, it shows that there is a deterministic relationship between radar signal attenuation and the amount of chloride and moisture in bridge deck concrete, and that when moisture content is known it is possible to estimate chloride quantity based on signal loss or attenuation measurements. Our research also demonstrates the practical application of this concept by utilizing GPR along with limited coring (three or more core samples) and laboratory chloride measurements to produce an accurate and quantitative, spatial mapping of chlorides in bridge decks.</p>

scholarly journals On Some Aspects of the Interaction of the Pulse and the Medium during the Vertical Echo Sounding of Glaciers

1975 ◽  
Vol 15 (73) ◽  
pp. 469-469
Author(s):  
G. V. Trepov ◽  
B. A. Fedorov ◽  
G. P. Khokhlov
Keyword(s):  
Electromagnetic Waves ◽  
Signal Propagation ◽  
Surface Velocity ◽  
Radar Signal ◽  
List Type ◽  
Signal Attenuation ◽  
Fluctuation Pattern ◽  
Effective Temperatures ◽  
Radar Signals ◽  
Representative Samples

The paper discusses three aspects of the interaction of a radar pulse and the medium which is being sounded, that is the glacier proper and the lower scattering surface. These aspects are: Radar signals attenuation during vertical sounding.The rale of radar signal propagation through the glacier.Fluctuations of radar signals during horizontal movements.Representative samples of signal attenuation were chosen for two points in the vicinity of Mirny station in Antarctica, these samples were obtained under roughly constant temperature conditions of the ice. The scattering properties of the bedrock are shown to be the controlling factor. Histograms of attenuation for these two points are given; effective temperatures of the ice were estimated.The measurements of the propagation velocity of electromagnetic waves were made along paths near “Molodezhnaya” station. Interesting results were obtained. The curves of the variation of the amplitude of reflected pulses were obtained for a number of short-distance paths with the radar moving horizontally, the working radar frequencies were 60, 213 and 440 MHz. Radii of autocorrelation of signal fluctuations were estimated. The fluctuation pattern along each of the paths is shown to be stable in time provided the distance is short enough. Measurement of the surface velocity of ice sheet movement by the transition of the fluctuation pattern in time seems quite promising.

Simulation of Radar Signal Propagation via Multipath

2018 ◽  
Author(s):  
Alicia Sudol ◽  
Seth E. Gordon ◽  
Hallie Ford ◽  
Eric Inclan ◽  
Dimitri N. Mavris ◽  
...  
Keyword(s):  
Signal Propagation ◽  
Radar Signal

scholarly journals Effects of propagation conditions on radar beam-ground interaction: impact on data quality

2005 ◽  
Vol 2 ◽  
pp. 201-208 ◽  
Author(s):  
A. Fornasiero ◽  
P. P. Alberoni ◽  
R. Amorati ◽  
L. Ferraris ◽  
A. C. Taramasso
Keyword(s):  
Data Processing ◽  
Data Quality ◽  
General Scheme ◽  
Signal Propagation ◽  
Radar Data ◽  
Radar Signal ◽  
Ground Clutter ◽  
Combined Algorithm ◽  
Radar Data Processing ◽  
Processing Steps

Abstract. A large part of the research in the radar meteorology is devoted to the evaluation of the radar data quality and to the radar data processing. Even when, a set of absolute quality indexes can be produced (like as ground clutter presence, beam blockage rate, distance from radar, etc.), the final product quality has to be determined as a function of the task and of all the processing steps. In this paper the emphasis lies on the estimate of the rainfall at the ground level taking extra care for the correction for ground clutter and beam blockage, that are two main problems affecting radar reflectivity data in complex orography. In this work a combined algorithm is presented that avoids and/or corrects for these two effects. To achieve this existing methods are modified and integrated with the analysis of radar signal propagation in different atmospheric conditions. The atmospheric refractivity profile is retrieved from the nearest in space and time radiosounding. This measured profile is then used to define the `dynamic map' used as a declutter base-field. Then beam blockage correction is applied to the data at the scan elevations computed from this map. Two case studies are used to illustrate the proposed algorithm. One is a summer event with anomalous propagation conditions and the other one is a winter event. The new algorithm is compared to a previous method of clutter removal based only on static maps of clear air and vertical reflectivity continuity test. The improvement in rain estimate is evaluated applying statistical analysis and using rain gauges data. The better scores are related mostly to the ``optimum" choice of the elevation maps, introduced by the more accurate description of the signal propagation. Finally, a data quality indicator is introduced as an output of this scheme. This indicator has been obtained from the general scheme, which takes into account all radar data processing steps.

scholarly journals On Some Aspects of the Interaction of the Pulse and the Medium during the Vertical Echo Sounding of Glaciers

1975 ◽  
Vol 15 (73) ◽  
pp. 469
Author(s):  
G. V. Trepov ◽  
B. A. Fedorov ◽  
G. P. Khokhlov
Keyword(s):  
Electromagnetic Waves ◽  
Signal Propagation ◽  
Surface Velocity ◽  
Radar Signal ◽  
List Type ◽  
Signal Attenuation ◽  
Fluctuation Pattern ◽  
Effective Temperatures ◽  
Radar Signals ◽  
Representative Samples

The paper discusses three aspects of the interaction of a radar pulse and the medium which is being sounded, that is the glacier proper and the lower scattering surface. These aspects are: Radar signals attenuation during vertical sounding. The rale of radar signal propagation through the glacier. Fluctuations of radar signals during horizontal movements. Representative samples of signal attenuation were chosen for two points in the vicinity of Mirny station in Antarctica, these samples were obtained under roughly constant temperature conditions of the ice. The scattering properties of the bedrock are shown to be the controlling factor. Histograms of attenuation for these two points are given; effective temperatures of the ice were estimated. The measurements of the propagation velocity of electromagnetic waves were made along paths near “Molodezhnaya” station. Interesting results were obtained. The curves of the variation of the amplitude of reflected pulses were obtained for a number of short-distance paths with the radar moving horizontally, the working radar frequencies were 60, 213 and 440 MHz. Radii of autocorrelation of signal fluctuations were estimated. The fluctuation pattern along each of the paths is shown to be stable in time provided the distance is short enough. Measurement of the surface velocity of ice sheet movement by the transition of the fluctuation pattern in time seems quite promising.

scholarly journals ANALYSIS OF MULTIPATH PIXELS IN SAR IMAGES

2016 ◽  
Vol XLI-B7 ◽  
pp. 873-877
Author(s):  
J. W. Zhao ◽  
J. C. Wu ◽  
X. L. Ding ◽  
L. Zhang ◽  
F. M. Hu
Keyword(s):  
Mean Amplitude ◽  
Signal Propagation ◽  
Propagation Path ◽  
Radar Signal ◽  
Mutual Position ◽  
Physical Parameters ◽  
Sar Images ◽  
Radar Images ◽  
Real Model ◽  
Imaging Simulation

As the received radar signal is the sum of signal contributions overlaid in one single pixel regardless of the travel path, the multipath effect should be seriously tackled as the multiple bounce returns are added to direct scatter echoes which leads to ghost scatters. Most of the existing solution towards the multipath is to recover the signal propagation path. To facilitate the signal propagation simulation process, plenty of aspects such as sensor parameters, the geometry of the objects (shape, location, orientation, mutual position between adjacent buildings) and the physical parameters of the surface (roughness, correlation length, permittivity)which determine the strength of radar signal backscattered to the SAR sensor should be given in previous. However, it's not practical to obtain the highly detailed object model in unfamiliar area by field survey as it's a laborious work and time-consuming. In this paper, SAR imaging simulation based on RaySAR is conducted at first aiming at basic understanding of multipath effects and for further comparison. Besides of the pre-imaging simulation, the product of the after-imaging, which refers to radar images is also taken into consideration. Both Cosmo-SkyMed ascending and descending SAR images of Lupu Bridge in Shanghai are used for the experiment. As a result, the reflectivity map and signal distribution map of different bounce level are simulated and validated by 3D real model. The statistic indexes such as the phase stability, mean amplitude, amplitude dispersion, coherence and mean-sigma ratio in case of layover are analyzed with combination of the RaySAR output.

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