Ground Penetrating Radars

Received: May 15, 2015
Accepted: September 16, 2015
Authors: 
V.I. Pravda, O.D. Mrachkovskyj, A.O. Abramovych

NTUU "KPI"

Georadars - a modern geophysical instrument, the use of which for non-destructive research allows monitoring environment at shallow depths with high detail, making it unique among other geophysical equipment.
The method is the reflection of electromagnetic waves radiated from the interface layers with different dielectric constants.
These limits can be both geological features and local heterogeneity of various origins (voids).
Georadars consists of three main parts: antenna unit (consisting of the transmitting and receiving antennas), received signal processing unit and computing unit for visualization and interpretation of data. The maximum depth of 50 meters is limited research in the environment of low attenuation (dry soil).
    Georadars working on the following principles:
• Method of electromagnetic induction
• Pulse method
The article is a description of existing principles of building modern ground penetrating radar, an indication of the positive and negative characteristics of each of them, prompting the current lineup and analysis of promising directions and methods for creating new ground penetrating radar.    
Pulse method
Ground penetrating radar, built on this principle, using short duration pulses for remote sensing. In reflection of the heterogeneity of the study is a change of the signal depending on the electrical properties of heterogeneity. Used pulses of 100 nsec (low resolution at depths - 10-40 m) to 0.5 nsec (with high resolution up to 0.5 m).
Method of electromagnetic induction
Electromagnetic induction method can detect metal objects around them when creating an alternating electromagnetic field.
Use two sensor coils in the search, one of which is radiating, and the second - selection. Availability between metal coils changes inductive connection between them, therefore there is a difference signal in the receiving coil. The signal reflected from the metal changes its phase.
 One of the most widely used ground penetrating radar device type is takoho company Schiebel AN19 / 2. Ground penetrating radar detects this type of 0.15 g of black metal to a depth of 10 cm and a typical anti-tank mine in a metal casing to a depth of 50 cm.
WAYS OF FURTHER RESEARCH
Further studies on the subject are as ground penetrating radar to develop methods for processing the received signal to be able to classify the type of target that is hidden in a dielectric medium.