Grating lobe suppression in an array antenna with element spacing greater than a half wavelength

The element allocation is formulated to suppress grating lobes in an array antenna with element spacing greater than a half wave-length. The number of the driven elements should be constant between lines of elements in order to eliminate larger periodicities than the element spacing. By this design, the sub-array shape can be kept identical. It is also easy to cope with linear polarizations. An array antenna with 192 elements was simulated and compared with the case of alternate allocations of driven and parasitic elements. It was shown that grating lobes are significantly suppressed by this design. Accordingly, the theoretical consideration has been confirmed.