| dc.description.abstract | Ground Penetrating Radar (GPR) is one of the non-destructive methods which
employ electromagnetic waves of frequency that ranges from few MHz to tens of GHz
to map the buried features inside the ground or man-made structures. In transmitter and
receiver parts of GPR, the demand for high gain, wideband and small antenna is
increasing, owing to its benefits such as deeper signal penetration, ability to carry higher
data rate and easy to handle particularly when space is a constraint. Instead of antenna,
geological aspects such as soil types, humidity and soil temperature need to be
considered as well since it has a significant effect to the GPR measurement
performance. The GPR measurement results are much dependent on the geological
aspects, for example, soil condition of different areas has different properties. The other
important parameter of GPR system is the microwave imaging technique. This
technique is required to map the buried object into 2-dimensinal graphical form and
finally shows the overall performances of the GPR system. In order to fulfil these
requirements, the methodology in this thesis is divided into three phases. In Phase I, the
design of the Slotted Bowtie Antenna (SBA) and Notch Circular Patch (NCP) which
have low ringing field, light weight and wideband characteristic frequency that ranges
from 1.25 GHz to 3.0 GHz and 0.5 GHz to 3.0GHz respectively, is proposed. In order to
obtain higher gain, a metallic reflector has been located at the back of the antennas and
the performances of the proposed antenna in term of S-parameter, radiation pattern and
gain is observed. The antennas are fabricated using Taconic TLY-5 and the measured
performances are compared and analysed. Both antennas have a good agreement for
simulated and measured results such as wide bandwidth which are higher than 60% for
SBA and 150% for NCP antennas, higher gain more than 8 dB and have a directional
radiation pattern. In Phase II the geological aspect, Eight (8) types of soil samples in
local region (Perlis) have been collected to measure the dielectric properties in three (3)
different condition which are normal (ambience), wet (10% water content) and dry
(50oC). | en_US |
