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LANDMINES DETECTION USING GROUND PENETRATING RADAR.
MADE BY:-SOURABH KANT
Quick Intro to RadarElectromagnetic radiationUsually in the microwave frequencies
500 MHz into the 10s of GHzOperates with pulse-echo mechanism
Similar to ultrasoundUsually very narrow band
Except for Ground Penetrating Radar (GPR)
UF Mine Detection Technology
What does it do? Identifies landmines based
on GPR image What is it?
Neural network classifier GPR signal pre-processing
and pos-processing Neural network training
method
GPR IntroductionSimilar to ordinary radar
except: Uses lower frequencies
(25 MHz to a few GHz) Extremely wide band Antennas transmit
directly downApplications:
Search for buried objects Geological strata Search for land mines Archaeology
Ground Penetrating Radar
Ground penetrating radarhigh resolution
electromagnetic technique
to investigate shallow subsurface of the earth
images scattering of electromagnetic waves from buried objects
Frequently used similarly to seismology.
Geometry for GPR
Mine Detection Modeling
Mine hunting schematicBistatic antenna
arrangement (separate xmt/rcv)
Use Helmholtz equation to define a circuit model
This ultra wide band radar provides centimeter resolution to locate even small targets. There are two distinct types of GPR, time-domain and frequency domain. Time domain or impulse GPR transmits discrete pulses of nanosecond duration and digitizes the returns at GHz sample rates. Frequency domain GPR systems transmit single frequencies either uniquely, as a series of frequency steps, or as a chirp. The amplitude and phase of the return signal is measured. The resulting data is converted to the time domain. GPR operates by detecting the dielectric contrasts in the soils, which allows it to locate even non metallic mines.
The impulse GPR system developed in the International Research Centre for Telecommunications-transmission and Radar (IRCTR). Impulse GPR system comprises a Impulse generator, Transmitter, Receiver, Pulse extender, A/D converter, Processor and Visual display.
GPR ModelModel for EM wave to travel to reach mine (TNT).This can readily be converted to a transmission
line equivalent of EM wave propagation.
Each section of the abovepath can be replaced by a transmission line segment, model from wave equation.
GPR Transmission Line ModelThe values of the circuit parameters can be readily
derived from the transmission line equations.
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LjR
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V
CjGLjR
zVV
s
s
os
oZ
and,
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ADVANTAGES ¢ GPR has accurate measurements.¢ GPR locates even small targets.¢ It has been well founded by the defense.¢ GPR operates by detecting the dielectric soils which allows it to locate even no metallic mines.¢ Biological sensors can only operate for limited periods, but in GPR has no such limits.¢ GPR has been tested in different environmental conditions.DISADVANTAGES¢ The sensor such as GPR is larger and heavier.¢ GPR is more power hungry.¢ GPR can suffer falls alarm rates as high as metal detectors.
Development of GPR Models to Detect and Discriminate Landmines
Description: The objective is to develop a landmine detection technique or algorithm that isolates landmines, particularly plastic anti-personnel mines, from clutter-causing objects. This includes: Statistical modeling of different
Ground Penetrating Radar (GPR) systems’ performance
Sensitivity of the sensor and detection technique against simulated or inert landmines
Space-Time Adaptive Processing (STAP) as applied to GPR
Design of robust processors which improve processor performance in terms of convergence, SINR, computational and numerical complexity
R RRRR
R
TR TRAir
SandClay
Granite
Test Bed Layout
Impulse GPR system is using for detecting anti-tank and anti-personal mines. Anti-tank mines are using for destroying the vehicles and anti-personal mines, which are designed to kill and maim people. Currently, very little technology is used in real-world demining activities. Active programs by the U.S Army in both land mine detection sensor development and systems integration are evaluating new technologies, incrementally improving existing technologies, increasing the probability of detection, reducing the false alarm rate, and planning out useable deployment scenarios. Through iterative design, build test cycles, and blind and scored testing at Army mine lanes, steady progress is being made.
CONCLUSION
Global Military Expenditures and Demining Operations
SWOT AnalysisStrengths Built on mature GPR platform Allows for faster detection of mines Allows for significant reduction in false positives Allows for smaller demining teams resulting in net savings since the largest expense utilizing current metal detection technologies is the cost of labor. Weakness
Remains untested in field Out of over 750 different
types of mines, currently only recognizes approx. 200 types
Test Runs with Mine Shells
Combining NQR w. GPROne attractive way to combine these
technologies is to use GPR as a filter to select targets.
NQR can then be used to identify the nature of the suspicious reflecting source.
This could be a basis for a response to the solicitation mentioned previously .
Test Studies
THANK YOU