Dual-polarized low-profile 16×4 SIW cavity-backed patch array for direct broadcast satellite applications

We developed a cavity backed patch 16×4 array suitable for dual polarization. The array is designed based on a cluster of eight of 2×4 sub-array that are fed using coaxial probes. Two probes are used to feed the sub-arrays, one for each polarization, meanwhile long SIW guides are used for feeding these subarrays. The large array requires three layers. The top layer has the radiating microstrip patches, i.e. 8 clusters of 2×4 sub-arrays, and the middle layer has the backing SIW cavities (located under the patches), and the bottom layer has the extra layer for the feed waveguides. For both arrays, each patch element in the subarray is dual-fed by horizontal and vertical microstrip lines at orthogonal edges of the patches. In addition, a set of four patches were added to allow staggering of the microstrip dividers to reduce coupling and simplify feed.