Development of Multi-Cavity-Backed Stacked Multi-Resonator Microstrip Antenna.

This paper analyses the effect of introducing multi-cavity-backing up to four cavities on a two-layered suspended stacked one bottom four top rectangular microstrip antenna. The analysis brings out the concurrent enhancement of bandwidth, gain and isolation between two antennas with progressive cavity-backing up to three cavities. Compared to stacked rectangular microstrip antennas without cavity, the single and triple cavity-backed configurations yielded a 40% and 83% enhancement in bandwidth and 0.80 and 2.20 dB enhancement in gain, respectively. The proposed novel triple cavity-backed one bottom four top rectangular microstrip antenna yields a bandwidth of 65.2% and an average gain of 12.85 dBi with an efficiency of 89%. The triple cavity-backed configuration yielded cross-polarization of less than −50 dB in both E and H planes and two such proposed antennas with rim-to-rim separation of 0.35 λ0 give uniform isolation better than 40 dB covering the entire bandwidth. Measured results are in close agreement with the simulated one, which validates the performance of the antenna. The proposed antenna is deemed suitable for Through the Wall and Ground Penetrating Radar applications because of the improved characteristics offered by the proposed antenna in the S-band. [ABSTRACT FROM AUTHOR]