Reduced aperture low sidelobe patch array

This Letter presents the design of a reduced aperture low sidelobe 4 × 4 patch array whose aperture is much smaller than that of a conventional 4 × 4 patch array since the spacing between adjacent elements is less than l_o/2. Low sidelobes are achieved without implementing an aperture distribution. This results in more efficient patch elements of the array and therefore the overall gain is higher than that of a conventional array of the same aperture. Moreover, as patches are series-fed, the width of feed lines is not limited by patch impedances and no matching transformer is required in the design. The experiment shows that a gain of 15.3 dB at 16.5 GHz and a sidelobe level of -16.7 dB in the E-plane and -15.1 dB in the H-plane are achieved.