This thesis is devoted to analyzing of the Radar Cross Section (RCS) of rectangular patch
antenna using Metamaterial Absorber (MMA) and the analysis of its reducing techniques. The
addressed theme has a great complexity and it covers various areas that include designing and
optimization of target geometrical model of rectangular patch antenna structures and making it
compatible with respect to metamaterial geometry. Analyses have been made to optimize and
validate the structure performances that include numerical methods for electromagnetic field
computation, MMA behavior, characterization, extraction of parameters, antenna radiation
performance analyses, simulation, fabrication, testing, and optimization with back validating
the designs.
The MMA structure finds its applications in antenna designing for the reduction of
Monostatic and Bistatic RCS in stealth platform for lower detectable objects. However, there
is still more emphasis needed to devote for in-band frequency response for low RCS of the
antenna. Therefore, making these assumptions, we have been proposing novel designs of
single-band, dual-band, and triple-band MMA structures. These structures provide significant
scattering characteristics and offering flexibility to the designer to control and tune the resonant
frequency, based on the specific applications as compared to that of the other MMAs in the
microwave regime of the Electromagnetic (EM) spectrum.
To explore the research scope, a three dimensional Frequency Selective Surface (FSS)
structure has been analyzed and its simulation responses with respect to parametric analyses
have been made. The research investigation further extended to Electronic Band Gap (EBG)
Structure and Defected Ground Structure (DGS). A hybrid structure of patch antenna is
proposed and designed for an inset feed rectangular microstrip patch antenna operating at 2.45
GHz in the Industrial, Scientific, and Medical (ISM) band. This hybrid structure claims the size
reduction, bandwidth, and gains enhancement.
The main focus of this research work is limited to determine the potential and practical
feasibility of MMA’s to enhance the stealth performance of rectangular patch antennas. For this
purpose, Monostatic and Bistatic RCS simulation and measurements are carried out in an
anechoic chamber and practical methods for Radar Cross Section reduction are discussed and
analyzed
