In another example, the dielectric substrates of the second plurality of edge antenna elements each has a second dielectric constant and the dielectric substrates of the third plurality of central antenna elements each has a third dielectric constant, the second dielectric constant being higher than the first dielectric constant, and the third dielectric constant being higher than the second dielectric constant.

In one example, the dielectric substrate is a multi-layer dielectric substrate, and the conductive patch includes a top patch disposed on a first surface of the multi-layer dielectric substrate and a bottom patch disposed within the multi-layer dielectric substrate below the top patch. Each microstrip antenna element may further include a ground plane disposed on a second surface of the multi-layer dielectric substrate below the bottom patch. Each microstrip antenna element may further include a waveport configured to couple RF signals into and out of the microstrip antenna element. In one example, the waveport includes an RF stripline feed and H-shaped open aperture on the ground plane.

In another example, the dielectric substrates of the first plurality of corner antenna elements each has a density that is lower than a density of the dielectric substrates of the second plurality of edge antenna elements and the third plurality of central antenna elements.