Referring again to FIG. 2, in certain examples the substrate structure shown in FIGS. 8A and 8B, or variations thereof, may be used for one or more of the layers of the multi-layer substrate 230. For example, a cavity structure may be formed in the substrate layer that is between the top patch 210 and the bottom patch 220 to laterally vary the density, as discussed above. Alternatively, or in addition, a cavity structure may be formed in the substrate layer that is between the bottom patch 220 and the ground plane 240. In examples in which both layers of the substrate 230 include cavity patterns, those patterns may be the same or different, and may be selected to optimize the performance of the antenna element 200 in the array in which it is to be used. In further examples, the macroscopic density and/or dielectric constant of any one or more of the layers of the multi-layer substrate 230 may be varied using a technique other than frame structuring. For example, as the multi-layer substrate 230 is formed by additive manufacturing, different materials, having different densities and/or dielectric constants, can be printed in different regions of the substrate 230 and/or selected for different antenna elements. In addition, certain low-loss RF materials can be printed in a form having a porous foam structure, to lower the density thereof. The flexibility of additive manufacturing approaches allows any of these techniques and materials to be applied in any of the antenna elements 200 in an array to produce a phases array having improved or optimized performance through the mitigation of the corner/edge effect, as discussed above. Further, these improvements can be obtained while allowing the phased array to maintain the same profile level across all the antenna elements, which may be desirable for maintenance convenience as well as radome flush mounting over the entire antenna aperture front. In addition, the phased array antenna may be capable of operating over the same bandwidth with corner/edge effect mitigation applied. That is, no loss in operating bandwidth may be caused by applying corner/edge effect mitigation according to the techniques and approaches disclosed herein.