Design and performance of large phased arrays of aperture stacked patches

We present a technique to achieve large-bandwidth and low-profile printed phased arrays that can give good sky coverage; that is, a reasonable scan range and, therefore, may be suited to applications such as radio astronomy. The microstrip arrays consist of aperture stacked patches and can exhibit VSWR <2:1 bandwidths in excess of an octave over a scanning range of /spl plusmn/45/spl deg/ in the principal planes. A thorough investigation of these microstrip phased arrays is given using an infinite array analysis and a design strategy to achieve broad-band characteristics is proposed. It is shown that the element spacing and the dielectric material thicknesses are critical in optimizing the scan/bandwidth performance.