A slot coupled microstrip antenna with a thick ground plane

Analysis and equivalent circuit of aperture‐coupled cavity‐fed microstrip patch antenna

“…Variation of the series impedance of the antenna with respect to the aperture length L a1 is shown in Figure 5(b). The amount of signal coupling from a microstripline feed to aperture 1 increases with L a1 , which results in increasing R 1 . From the present theory, susceptance B f (Y f ϭ G f ϩ jB f ) is negative, and its magnitude decreases as L a1 increases; hence, the resonant frequency decreases.…”

“…Recently, a thick ground plane has been added to aperture-coupled microstrip patch antennas (especially for active phased-array antenna applications) in order to serve as a heat sink for active TR modules and provide structural support for thin substrates [1,2]. However, the coupling to the patch decreases rapidly with increasing ground-plane thickness since the thick slot behaves as a waveguide below cutoff [2].…”

“…Electrodynamics of substances with simultaneously negative values of electric permittivity and magnetic permeability studied by Veselago in the late 1960s [1], has recently found its application in artificial composite materials. Left-handed materials (LHMs), as they are also known, have been widely investigated [2][3][4] and various structures have been experimentally realized at microwaves [5][6][7].…”