1. Dr. Sergey BondarenkoDr. Sergey Bondarenko
Email: Serge.Bondarenko@gmail.comEmail: Serge.Bondarenko@gmail.com

2.  The main difference between the approaches is object primary registration method. The firstThe main difference between the approaches is object primary registration method. The first
is based on wave reflection only, the second one can also use wave attenuationis based on wave reflection only, the second one can also use wave attenuation
 It follows surface units are unburied or slightly buried in contrast to borehole unitsIt follows surface units are unburied or slightly buried in contrast to borehole units
 However cross borehole techniques provide twice more underground space observationHowever cross borehole techniques provide twice more underground space observation
with equal system dynamic range for the both radarswith equal system dynamic range for the both radars
 Generally the both techniques allow computer tomography data processing and haveGenerally the both techniques allow computer tomography data processing and have
similar topography and differ only “borehole deepness”similar topography and differ only “borehole deepness”
 The most important part of UWB radar is RF unit especially buried wideband antennaThe most important part of UWB radar is RF unit especially buried wideband antenna
 The most important process is energy accumulation: on the transmitter side (a few MW inThe most important process is energy accumulation: on the transmitter side (a few MW in
a short pulse like GPR “Loza”) or on the receiver side (stepped frequency continuous wavea short pulse like GPR “Loza”) or on the receiver side (stepped frequency continuous wave
(SFCW) like 3d-Radar MARA Nord)(SFCW) like 3d-Radar MARA Nord)
 Nowadays the both technologies are intensively developed for different applications (see,Nowadays the both technologies are intensively developed for different applications (see,
for example, LWD Borehole Radar presentation)for example, LWD Borehole Radar presentation)
 Under “unlimited processing time” SFCW approach becomes more attractive allowing toUnder “unlimited processing time” SFCW approach becomes more attractive allowing to
use both pulse synthesis method and multi-frequency phase processing method.use both pulse synthesis method and multi-frequency phase processing method.
2

3. 3
t
ufu
t
Δf
Δt
Direct Synthesis
Synthesis by
Weighted Processing

4. 4
f=1000 МГцf=100 МГц

5. 5
UWB Surface Based Radar TechnologyUWB Surface Based Radar Technology
for Tunnel Detection (Square Monitoring)for Tunnel Detection (Square Monitoring)
Transmitters (Tx) radiate power into the ground. Receivers (Rx) collect the received field and send the informationTransmitters (Tx) radiate power into the ground. Receivers (Rx) collect the received field and send the information
to the main station at a drone for tomography processing. Due to option of one way propagation mode and theto the main station at a drone for tomography processing. Due to option of one way propagation mode and the
object primary registration method based on wave attenuation in addition to wave reflection the distancesobject primary registration method based on wave attenuation in addition to wave reflection the distances
between transmitters and receivers can be a big enough (tens or hundreds meters depending on groundbetween transmitters and receivers can be a big enough (tens or hundreds meters depending on ground
parameters).parameters).

6. 6
UWB Borehole Radar TechnologyUWB Borehole Radar Technology
for Tunnel Detection (Borderline Monitoring 1)for Tunnel Detection (Borderline Monitoring 1)
Ground Penetrating Radar (GPR) methodology. Transmitter (Tx) of the transceiver unit radiates powerGround Penetrating Radar (GPR) methodology. Transmitter (Tx) of the transceiver unit radiates power
driving along the borderline into the horizontal borehole. Receiver (Rx) of the unit collects thedriving along the borderline into the horizontal borehole. Receiver (Rx) of the unit collects the
scattered field during the drive and produces D-scan.scattered field during the drive and produces D-scan.
Tx Tx
Tx
Rx Rx
Rx
Tunnel

7. 7
UWB Borehole Radar TechnologyUWB Borehole Radar Technology
for Tunnel Detection (Borderline Monitoring 2)for Tunnel Detection (Borderline Monitoring 2)
A few vertical boreholes along borderline are used. Transmitter radiates power (Tx) driving into a oneA few vertical boreholes along borderline are used. Transmitter radiates power (Tx) driving into a one
borehole. Receiver (Rx) collects the penetration field during the drive into the other borehole.borehole. Receiver (Rx) collects the penetration field during the drive into the other borehole.
Collected information is used for tomography processing.Collected information is used for tomography processing.
Penetration
field
TunnelTunnel

8.  The main advantage of the radar method is a high constant difference of theThe main advantage of the radar method is a high constant difference of the
permittivity between tunnel (permittivity between tunnel ( εεrr ≈≈ 11 ) and around space () and around space ( εεrr ≥≥ 4-64-6 ) for use of the) for use of the
reflective method on a one hand and significant tunnel width (reflective method on a one hand and significant tunnel width (more than 2 metersmore than 2 meters))
for use of the attenuation method on the otherfor use of the attenuation method on the other
 Nowadays there is a good opportunity to gather three well developed techniques,Nowadays there is a good opportunity to gather three well developed techniques,
namely, tomography reconstruction, UWB radar (GPR) and digital directnamely, tomography reconstruction, UWB radar (GPR) and digital direct
synthesizer (DDS) to successfully solve tunnel detection problemsynthesizer (DDS) to successfully solve tunnel detection problem
 At last, combination acoustic (“hammer”) and UWB radar methods is reasonableAt last, combination acoustic (“hammer”) and UWB radar methods is reasonable
 There are many complete or good verified independent results in all these fieldsThere are many complete or good verified independent results in all these fields
 The mainstream is right coordination of independent research and technologicalThe mainstream is right coordination of independent research and technological
resources.resources.
Thank you for attention.Thank you for attention.
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