ABSTRACT
Microstrip patch antennas were first proposed in the early 1970s and since then a plethora of activity in this area of antenna engineering has occurred, probably more than in any other field of antenna research and development. Over the years there have been many conductor shapes proposed and investigated for a microstrip patch antenna. Edge-fed patches have several advantages over other feeding techniques. One of the key features of the technology is its ease of fabrication, because the feed layout and patches can be etched on one board. Probe feeding a microstrip patch antenna is another form of the original excitation methods proposed in the mid-1970s. Probe-fed microstrip patches have similar issues to edge-fed patches; namely, their bandwidth is somewhat small and these printed antennas are somewhat difficult to accurately analyze. The aperture-coupled patch has more design parameters than the direct contact fed patches and therefore has more flexibility or degrees of freedom for the antenna designer.
