Design and Applications of Multi-Frequency Holographic Subsurface Radar: Review and Case Histories

Holographic subsurface radar (HSR) is not currently in widespread usage. This is due to a historical perspective in the ground-penetrating radar (GPR) community that the high attenuation of electromagnetic waves in most media of interest and the inability to apply time-varying gain to the continuous-wave (CW) HSR signal preclude sufficient effective penetration depth. While it is true that the fundamental physics of HSR, with its use of a CW signal, does not allow amplification of later (i.e., deeper) arrivals in lossy media (as is possible with impulse subsurface radar (ISR)), HSR has distinct advantages. The most important of these is the ability to do shallow subsurface imaging with a resolution that is not possible with ISR. In addition, the design of an HSR system is simpler than for ISR due to the relatively low-tech transmitting and receiving antennae. This paper provides a review of the main principles of HSR through an optical analogy and describes possible algorithms for radar hologram reconstruction. We also present a review of the history of development of systems and applications of the RASCAN type, which is possibly the only commercially available holographic subsurface radar. Among the subsurface imaging and remote sensing applications considered are humanitarian demining, construction inspection, nondestructive testing of dielectric aerospace materials, surveys of historic architecture and artworks, paleontology, and security screening. Each application is illustrated with relevant data acquired in laboratory and/or field experiments.

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Design and Applications of Multi-Frequency Holographic Subsurface Radar: Review and Case Histories

10.20944/preprints202106.0059.v1 ◽

2021 ◽

Author(s):

Sergey I. Ivashov ◽

Lorenzo Capineri ◽

Tim Bechtel ◽

Masaharu Inagaki ◽

Vladimir Razevig ◽

...

Keyword(s):

Electromagnetic Waves ◽

Field Experiments ◽

Continuous Wave ◽

Subsurface Imaging ◽

Shallow Subsurface ◽

High Attenuation ◽

Sensing Applications ◽

History Of ◽

Boring Insect ◽

Ground Penetrating

Holographic subsurface radar (HSR) is currently not in widespread usage. This is due to an historical perspective in the ground penetrating radar (GPR) community that the high attenuation of electromagnetic waves in most media of interest, and the inability to apply time-varying gain to the continuous wave (CW) HSR signal precludes sufficient effective penetration depth. While it is true that the fundamental physics of HSR, with its use of a CW signal, does not allow amplification of later (i.e. deeper) arrivals in lossy media (as is possible with impulse subsurface radar — ISR), HSR has distinct some distinctive advantages. The most important of these is the ability to do shallow subsurface imaging with a resolution that is not possible with ISR. In addition, the design of an HSR system is simpler than for ISR due to the relatively low-tech transmitting and receiving antennae. This paper provides a review of the main principles of HSR through an optical analogy and describes possible algorithms for radar hologram reconstruction. We also present a review of the history of development of systems and applications for HSR of the “RASCAN” type which is possibly the only holographic subsurface radar that is produced in lots. Among the subsurface imaging and remote sensing applications considered are humanitarian demining, construction inspection, surveys of historic architecture and artworks, nondestructive testing of dielectric aerospace materials, security applications, paleontology, detection of wood-boring insect damage, and others. Each application is illustrated with relevant data acquired in laboratory and/or field experiments.

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Design and Applications of Multi-Frequency Holographic Subsurface Radar: Review and Case Histories

10.20944/preprints202105.0321.v1 ◽

2021 ◽

Author(s):

Sergey I. Ivashov ◽

Lorenzo Capineri ◽

Tim Bechtel ◽

Masaharu Inagaki ◽

Vladimir Razevig ◽

...

Keyword(s):

Electromagnetic Waves ◽

Field Experiments ◽

Continuous Wave ◽

Subsurface Imaging ◽

Shallow Subsurface ◽

High Attenuation ◽

Sensing Applications ◽

History Of ◽

Boring Insect ◽

Ground Penetrating

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Design and Applications of Multi-Frequency Holographic Subsurface Radar: Review and Case Histories

10.20944/preprints202108.0158.v1 ◽

2021 ◽

Author(s):

Sergey I. Ivashov ◽

Lorenzo Capineri ◽

Tim Bechtel ◽

Masaharu Inagaki ◽

Vladimir Razevig ◽

...

Keyword(s):

Electromagnetic Waves ◽

Field Experiments ◽

Continuous Wave ◽

Subsurface Imaging ◽

Security Screening ◽

Shallow Subsurface ◽

Sensing Applications ◽

History Of Development ◽

History Of ◽

Ground Penetrating

Holographic subsurface radar (HSR) is not currently not in widespread usage. This is due to an historical perspective in the ground penetrating radar (GPR) community that the high attenuation of electromagnetic waves in most media of interest, and the inability to apply timevarying gain to the continuous wave (CW) HSR signal precludes sufficient effective penetration depth. While it is true that the fundamental physics of HSR, with its use of a CW signal, does not allow amplification of later (i.e. deeper) arrivals in lossy media (as is possible with impulse subsurface radar — ISR), HSR has distinct advantages. The most important of these is the ability to do shallow subsurface imaging with a resolution that is not possible with ISR. In addition, the design of an HSR system is simpler than for ISR due to the relatively low-tech transmitting and receiving antennae. This paper provides a review of the main principles of HSR through an optical analogy and describes possible algorithms for radar hologram reconstruction. We also present a review of the history of development of systems and applications for HSR of the “RASCAN” type which is possibly the only commercially available holographic subsurface radars. Among the subsurface imaging and remote sensing applications considered are humanitarian demining, construction inspection, nondestructive testing of dielectric aerospace materials, surveys of historic architecture and artworks, paleontology, and security screening. Each application is illustrated with relevant data acquired in laboratory and/or field experiments.

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WISDOM Antenna Pattern in the presence of Rover and Soil

10.5194/egusphere-egu21-14846 ◽

2021 ◽

Author(s):

Wolf-Stefan Benedix ◽

Dirk Plettemeier ◽

Christoph Statz ◽

Yun Lu ◽

Ronny Hahnel ◽

...

Keyword(s):

Pattern Matching ◽

Ground Penetrating Radar ◽

Electromagnetic Waves ◽

Complete System ◽

Near Field ◽

System Model ◽

Soil Types ◽

Broadband Antenna ◽

Shallow Subsurface ◽

Ground Penetrating

The WISDOM ground-penetrating radar aboard the 2022 ESA-Roscosmos Rosalind-Franklin ExoMars Rover will probe the shallow subsurface of Oxia Planum using electromagnetic waves. A dual-polarized broadband antenna assembly transmits the WISDOM signal into the Martian subsurface and receives the return signal. This antenna assembly has been extensively tested and characterized w.r.t. the most significant antenna parameters (gain, pattern, matching). However, during the design phase, these parameters were simulated or measured without the environment, i.e., in the absence of other objects like brackets, rover vehicle, or soil. Some measurements of the rover's influence on the WISDOM data were performed during the instrument's integration.It was shown that the rover structure and close surroundings in the near-field region of the WISDOM antenna assembly have a significant impact on the WISDOM signal and sounding performance. Hence, it is essential to include the simulations' environment, especially with varying surface and underground.With this contribution, we outline the influences of rover and ground on the antenna's pattern and particularly on the footprint. We employ a 3D field solver with a complete system model above different soil types, i.e., subsurface materials with various combinations of permittivity and conductivity.

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Radar Imager for Mars’ Subsurface Experiment—RIMFAX

Space Science Reviews ◽

10.1007/s11214-020-00740-4 ◽

2020 ◽

Vol 216 (8) ◽

Author(s):

Svein-Erik Hamran ◽

David A. Paige ◽

Hans E. F. Amundsen ◽

Tor Berger ◽

Sverre Brovoll ◽

...

Keyword(s):

Continuous Wave ◽

Sand Dunes ◽

Landing Site ◽

Wide Band ◽

Center Frequency ◽

Depth Range ◽

Fmcw Radar ◽

Shallow Subsurface ◽

Eventual Return ◽

Ground Penetrating

AbstractThe Radar Imager for Mars’ Subsurface Experiment (RIMFAX) is a Ground Penetrating Radar on the Mars 2020 mission’s Perseverance rover, which is planned to land near a deltaic landform in Jezero crater. RIMFAX will add a new dimension to rover investigations of Mars by providing the capability to image the shallow subsurface beneath the rover. The principal goals of the RIMFAX investigation are to image subsurface structure, and to provide information regarding subsurface composition. Data provided by RIMFAX will aid Perseverance’s mission to explore the ancient habitability of its field area and to select a set of promising geologic samples for analysis, caching, and eventual return to Earth. RIMFAX is a Frequency Modulated Continuous Wave (FMCW) radar, which transmits a signal swept through a range of frequencies, rather than a single wide-band pulse. The operating frequency range of 150–1200 MHz covers the typical frequencies of GPR used in geology. In general, the full bandwidth (with effective center frequency of 675 MHz) will be used for shallow imaging down to several meters, and a reduced bandwidth of the lower frequencies (center frequency 375 MHz) will be used for imaging deeper structures. The majority of data will be collected at regular distance intervals whenever the rover is driving, in each of the deep, shallow, and surface modes. Stationary measurements with extended integration times will improve depth range and SNR at select locations. The RIMFAX instrument consists of an electronic unit housed inside the rover body and an antenna mounted externally at the rear of the rover. Several instrument prototypes have been field tested in different geological settings, including glaciers, permafrost sediments, bioherme mound structures in limestone, and sedimentary features in sand dunes. Numerical modelling has provided a first assessment of RIMFAX’s imaging potential using parameters simulated for the Jezero crater landing site.

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High-resolution ultra-shallow subsurface imaging by integrating near-surface seismic reflection and ground-penetrating radar data in the depth domain

Journal of Applied Geophysics ◽

10.1016/j.jappgeo.2007.01.001 ◽

2007 ◽

Vol 62 (3) ◽

pp. 281-286 ◽

Cited By ~ 22

Author(s):

Steven D. Sloan ◽

Georgios P. Tsoflias ◽

Don W. Steeples ◽

Paul D. Vincent

Keyword(s):

High Resolution ◽

Ground Penetrating Radar ◽

Seismic Reflection ◽

Radar Data ◽

Subsurface Imaging ◽

Near Surface ◽

Shallow Subsurface ◽

Ground Penetrating

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Mapping anthropogenic fill with GPR for unmarked grave detection: A case study from a possible location of Mokare’s grave, Albany, Western Australia

10.31219/osf.io/pd9ex ◽

2021 ◽

Author(s):

Paul Bladon ◽

Ian Moffat ◽

David Guilfoyle ◽

Alice Beale ◽

Jennifer Milani

Keyword(s):

Western Australia ◽

Shallow Subsurface ◽

Non Invasive ◽

Disturbed Areas ◽

Historical Figure ◽

Invasive Method ◽

History Of ◽

A Site ◽

Ground Penetrating ◽

Colonial Settlement

Geophysical techniques are a commonly used, non-invasive method for the location of unmarked graves. Contrary to popular perception, most studies rely not on directly imaging skeletal material but instead on locating the subsurface disturbance created by grave digging. This approach is effective only when sufficient contrast exists between detectable properties (such as structure, mineralogy or porosity) of the grave fill and the surrounding sediment. Resolving these features can be particularly problematic in disturbed areas where other anthropogenic fill is in place, as it is often complex in character and lacks a natural stratigraphy.In many cultural heritage projects, it is often more important to ensure that burials are not disturbed rather than to specifically locate them. Under these circumstances, ground penetrating radar (GPR) can be used to locate modern anthropogenic fill. This may show which areas of the site are younger than the targeted graves and therefore of no archaeological interest. This approach is trialled on a site thought to contain the grave of Mokare, a significant historical figure in the colonial settlement of the Albany area in Western Australia. The delineation of a package of modern fill in the shallow subsurface in the context of the probable history of earthworks on the site demonstrates that Mokare is not buried in the surveyed location. This approach, applied to suitable sites, could contribute to culturally sensitive non-invasive investigation of burial sites in other locations.

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WISDOM Calibration and Data Processing Pipeline for the ExoMars 2020 Mission

10.5194/egusphere-egu2020-19464 ◽

2020 ◽

Author(s):

Dirk Plettemeier ◽

Christoph Statz ◽

Yun Lu ◽

Wolf-Stefan Benedix ◽

Sebastian Hegler ◽

...

Keyword(s):

Data Processing ◽

Electromagnetic Waves ◽

Continuous Wave ◽

Field Measurements ◽

Processing Pipeline ◽

Martian Soil ◽

Wave Radar ◽

Past Life ◽

Manual Processing ◽

Ground Penetrating

The WISDOM instrument is part of the 2020 ESA-Roscosmos ExoMars Rosalind-Franklin rover payload. It is a fully-polarimetric ground penetrating RADAR (GPR) operating as a stepped-frequency continuous-wave radar at frequencies between 500 MHz and 3 GHz yielding a centimetric resolution and a penetration depth of about 3 m in Martian soil. WISDOMs primary scientific objective is the detailed characterization the material distribution of the Martian subsurface as a contribution to the search for evidence of present and past life.WISDOM&#160; works by transmitting electromagnetic waves in the observable zone of the subsurface below the antenna. The transfer function of the observed zone is then recovered from the received signal. The processing of the WISDOM data involves several calibration steps, where environment and temperature as well as instrument influences are compensated in order to obtain interpretable results. The data processing involves several filters that are designed to extract and quantify features of interest w.r.t. the surface and subsurface. Calibration and processing are implemented in the WISDOM Data Processing Framework (WDPF). It can be operated manually (via GUI integration) as well as automatically as part of the ROCC processing pipeline yielding comparable and reproducible results from automatic and manual processing of WISDOM data. The capabilities of WDPF are validated on laboratory and field measurements performed with the WISDOM instrument.

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A review of ground-penetrating radar studies related to peatland stratigraphy with a case study on the determination of peat thickness in a northern boreal fen in Quebec, Canada

Progress in Physical Geography Earth and Environment ◽

10.1177/0309133313501106 ◽

2013 ◽

Vol 37 (6) ◽

pp. 767-786 ◽

Cited By ~ 11

Author(s):

Sandra Proulx-McInnis ◽

André St-Hilaire ◽

Alain N. Rousseau ◽

Sylvain Jutras

Keyword(s):

Ground Penetrating Radar ◽

Electromagnetic Waves ◽

Open Water ◽

Coefficient Of Determination ◽

Cross Sectional ◽

Soil Thickness ◽

Shallow Subsurface ◽

Observation Method ◽

Time Required ◽

Ground Penetrating

Ground-penetrating radar (GPR) is a non-intrusive geophysical observation method based on propagation and reflection of high-frequency electromagnetic waves in the shallow subsurface. The vertical cross-sectional images obtained allow the identification of thickness and lithologic horizons of different media, without destruction. Over the last decade, several studies have demonstrated the potential of GPR. This paper presents a review of recent GPR applications to peatlands, particularly to determine peat stratigraphy. An example study of acquisition and comparison of peatland soil thickness of a fen-dominated watershed located in the James Bay region of Quebec, using (1) a meter stick linked to a GPS RTK and (2) a GSSI GPR, is given. A coefficient of determination ( r2) of 56% was obtained between the ordinary krigings performed on data gathered using both techniques. Disparities occurred mainly in the vicinity of ponds which can be explained by the attenuation of GPR signal in open water. Despite these difficulties – the higher time required for analysis and the error margin – it seems more appropriate to use a GPR, instead of a graduated rod linked to a GPS, to measure the peat depths on a site like the one presented in this study. Manual measurements, which are user-dependent in the context of variable mineral substrate densities and with the presence of obstacles in the substrate, may be more subjective.

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Mapping Subsurface Drainage in Agricultural Areas Using a Frequency-Domain Ground Penetrating Radar

10.5194/egusphere-egu2020-1887 ◽

2020 ◽

Author(s):

Triven Koganti ◽

Ellen Van De Vijver ◽

Barry J. Allred ◽

Mogens H. Greve ◽

Jørgen Ringgaard ◽

...

Keyword(s):

Antenna Array ◽

Ground Penetrating Radar ◽

Continuous Wave ◽

Subsurface Drainage ◽

High Attenuation ◽

Local Soil ◽

Increased Risk ◽

3D Gpr ◽

Ground Penetrating ◽

Agricultural Areas

Artificial subsurface drainage systems are installed in agricultural areas to remove excess water and convert poorly naturally drained soils into productive cropland. Some of the most productive agricultural regions in the world are a result of subsurface drainage practices. Drain lines provide a shortened pathway for the release of nutrients and pesticides into the environment, which presents a potentially increased risk for eutrophication and contamination of surface water bodies. Knowledge of drain line locations is often lacking. This complicates the understanding of the local hydrology and solute dynamics and the consequent planning of mitigation strategies such as constructed wetlands, saturated buffers, bioreactors, and nitrate and phosphate filters. In addition, accurate knowledge of the existing subsurface drainage system is required in designing the installation of a new set of drain lines to enhance soil water removal efficiency. The traditional methods of drainage mapping involve the use of tile probes and trenching equipment which are time-consuming, tiresome, and invasive, thereby carrying an inherent risk of damaging the drain pipes. Non-invasive geophysical sensors provide a potential alternative solution to the problem. Previous research has focused on the use of time-domain ground penetrating radar (GPR) with variable success depending on local soil and hydrological conditions and the center frequency of the specific equipment used. For example, 250 MHz antennas proved to be more suitable for drain line mapping. Recent technological advancements enabled the collection of high-resolution spatially exhaustive data. In this study, we present the use of a stepped-frequency continuous wave (SFCW) 3D-GPR (GeoScope Mk IV 3D-Radar with DXG1820 antenna array) mounted in a motorized survey configuration with real-time georeferencing for subsurface drainage mapping. The 3D-GPR system offers more flexibility for application to different (sub)surface conditions due to the coverage of wide frequency bandwidth (60-3000 MHz). In addition, the wide array swathe of the antenna array (1.5 m covered by 20 measurement channels) enables effective coverage of three-dimensional (3D) space. The surveys were performed on twelve different study sites with various soil types with textures ranging from sand to clay till. While we achieved good success in finding the drainage pipes at five sites with sandy, sandy loam, loamy sand and organic topsoils, the results at the other seven sites with more clay-rich soils were less successful. The high attenuation of electromagnetic waves in highly conductive clay-rich soils, which limits the penetration depth of the 3D-GPR system, can explain our findings obtained in this research.

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