Experimental observation of the creeping-wave phenomenon in backscatter using a short-pulse radar system

1965 ◽  
Vol 53 (8) ◽  
pp. 1102-1104 ◽  
Author(s):  
D.E. Foreman ◽  
D.F. Sedivec
Keyword(s):  
Experimental Observation ◽  
Wave Phenomenon ◽  
Short Pulse ◽  
Radar System ◽  
Pulse Radar ◽  
Creeping Wave

Borehole radar applied to characterization of fracture zones

1989 ◽  
Vol 20 (2) ◽  
pp. 149 ◽  
Author(s):  
O. Olsson ◽  
L. Falk ◽  
O. Forslund ◽  
B. Niva ◽  
E. Sandberg
Keyword(s):  
Granitic Rock ◽  
Short Pulse ◽  
3D Models ◽  
Radar System ◽  
Fracture Zones ◽  
Borehole Logging ◽  
Single Hole ◽  
Pulse Radar ◽  
Borehole Radar

A new short-pulse radar system (RAMAC) developed by ABEM AB has now been in operation for three years during which more than 100 km of borehole logging has been performed. The bulk of the surveys have been in granites and gneisses.The RAMAC system operates at centre frequencies in the interval 20 to 60 MHz. At those frequencies single-hole reflection ranges of 50 to 150 m are normally obtained in gneissic and granitic rock. Cross-hole ranges have in some cases exceeded 300 m. The large probing range in combination with resolution of the order of a few metres makes borehole radar a unique technique for investigation of fracture zones in crystalline rock.Case histories illustrate application of the RAMAC system in three different configurations (single-hole reflection, cross-hole reflection, and cross-hole tomography) and demonstrate how combination of these three can yield consistent 3D models of fracture zones and other structures.

scholarly journals Antenna Parts and Waveguide Transmission Line of Short Pulse Radar System Design

2014 ◽  
Vol 14 (12) ◽  
Author(s):  
Maxim Golubtsov ◽  
Vasily Ovechkin ◽  
Natalia Fadeeva ◽  
Alexey Parschikov ◽  
Arkady Borisov
Keyword(s):  
Transmission Line ◽  
System Design ◽  
Short Pulse ◽  
Radar System ◽  
Pulse Radar ◽  
Waveguide Transmission

A New Ultra Wideband, Short Pulse, Radar System for Mine Detection

2002 ◽  
pp. 175-182 ◽  
Author(s):  
F. Gallais ◽  
V. Mallepeyre ◽  
Y. Imbs ◽  
B. Beillard ◽  
J. Andrieu ◽  
...  
Keyword(s):  
Short Pulse ◽  
Radar System ◽  
Ultra Wideband ◽  
Mine Detection ◽  
Pulse Radar

scholarly journals Airborne River-Ice Thickness Profiling with Helicopter-Borne UHF Short-Pulse Radar

1987 ◽  
Vol 33 (115) ◽  
pp. 330-340 ◽  
Author(s):  
Steven A Arcone ◽  
Allan J Delaney
Keyword(s):  
Short Pulse ◽  
Hanging Wall ◽  
Open Water ◽  
High Water ◽  
High Water Content ◽  
Ice Thickness ◽  
Frazil Ice ◽  
Pulse Radar ◽  
Detailed Surface ◽  
Ice Conditions

AbstractThe ice-thickness profiling performance of a helicopter-mounted short-pulse radar operating at approximate center frequencies of 600 and 900 MHz was assessed. The antenna packages were mounted 1.2 m off the skid of a small helicopter whose speed and altitude were varied from about 1.8 to 9 m/s and 3 to 12 m. Clutter from the helicopter offered minimal interference with the ice data. Data were acquired in Alaska over lakes (as a proving exercise) and two rivers, whose conditions varied from open water to over 1.5 m of solid ice with numerous frazil-ice formations. The most readily interpretable data were acquired when the ice or snow surface was smooth. Detailed surface investigations on the Tanana River revealed good correlations of echo delay with solid ice depth, but an insensitivity to frazil-ice depth due to its high water content. On the Yukon River, coinciding temporally coherent surface and bottom reflections were associated with solid ice and smooth surfaces. All cases of incoherent surface returns (scatter) occurred over ice rubble. Rough-surface scattering was always followed by the appearance of bottom scattering but, in many cases, including a hanging-wall formation of solid frazil ice, bottom scattering occurred beneath coherent, smooth-surface reflections. Areas of incoherent bottom scattering investigated by drilling revealed highly variable ice conditions, including frazil ice. The minimum ice thickness that could be resolved from the raw data was about 0.2 m with the 600 MHz antenna and less than 0.15 m with the 900 MHz antenna.

scholarly journals Stratigraphic continuity in 400MHz short-pulse radar profiles of firn in West Antarctica

2004 ◽  
Vol 39 ◽  
pp. 195-200 ◽  
Author(s):  
Steven A. Arcone ◽  
Vandy B. Spikes ◽  
Gordon S. Hamilton ◽  
Paul A. Mayewski
Keyword(s):  
Short Pulse ◽  
Accumulation Rate ◽  
High Density ◽  
Thin Layers ◽  
East Antarctica ◽  
Relative Amplitude ◽  
Accumulation Rates ◽  
West Antarctica ◽  
Constructive Interference ◽  
Pulse Radar

AbstractWe track dated firn horizons within 400 MHz short-pulse radar profiles to find the continuous extent over which they can be used as historical benchmarks to study past accumulation rates in West Antarctica. The 30–40cm pulse resolution compares with the accumulation rates of most areas. We tracked a particular set that varied from 30 to 90 m in depth over a distance of 600 km. The main limitations to continuity are fading at depth, pinching associated with accumulation rate differences within hills and valleys, and artificial fading caused by stacking along dips. The latter two may be overcome through multi-kilometer distances by matching the relative amplitude and spacing of several close horizons, along with their pulse forms and phases. Modeling of reflections from thin layers suggests that the – 37 to – 50 dB range of reflectivity and the pulse waveforms we observed are caused by the numerous thin ice layers observed in core stratigraphy. Constructive interference between reflections from these close, high-density layers can explain the maintenance of reflective strength throughout the depth of the firn despite the effects of compaction. The continuity suggests that these layers formed throughout West Antarctica and possibly into East Antarctica as well.

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