The design of a monostatic, ultra wide band,VHF, pulse radar for detection of close-in targets
Date
2003-03
Authors
Van der Merwe, P. J.
Journal Title
Journal ISSN
Volume Title
Publisher
Stellenbosch : University of Stellenbosch
Abstract
Ground penetrating radar is currently proving itself as an invaluable tool for the prediction of
geological structures in the mining environment. Borehole radar is a specific application of this
technology, useful in the prediction of the course of rock layers between boreholes ahead of
mining. Establishing borehole radar as an industrial tool requires a system that is more userfriendly
and easier to deploy than the bi-static radar systems currently available.
The development of a monostatic radar system is discussed. It is an ultra wide band, pulse
radar system that operates at VHF (10-100 MHz). The system is required to detect reflections
from objects 5 m away and further. This translates to a total electromagnetic propagation time
of approximately 100 ns or more in the rock medium.
The complete design process - from fundamental requirements, through a conceptual design,
to a final electronic circuit - is discussed. The design is also built, measured in the laboratory
and taken for initial field trails. The following aspects are considered:
• Pulse generation by means of an original circuit based on power MOSFETs.
• Routing of the transmitted- and received signal between transmitter, receiver and
antenna. This is done using a novel, active quasi circulator topology.
• Methods of increasing isolation (actively and passively) between transmitter and
receiver.
• Interfacing with a specific receiver, antenna and data acquisition system.
Description
Thesis (MScEng (Electrical and Electronic Engineering))--University of Stellenbosch, 2003.
Keywords
Ground penetrating radar, Radar, Dissertations -- Electronic engineering, Theses -- Electronic engineering