Design of series-fed, aperture-coupled microstrip arrays

Series-fed resonant arrays of aperture-coupled antennas have been designed. Design curves have been generated that provide good accuracy when used in conjunction with standard array design methods. Arrays fabricated with these methods have demonstrated low sidelobe levels without special timing. An error analysis has demonstrated low sidelobe levels without special tuning. An error analysis has demonstrated that the primary limiting factor in low sidelobe performance was fabrication tolerances associated with the resonant length of the patch radiators. The errors in the resonant length of the patch antennas were estimated to be approximately +or-50 mu m and this produces about +or-14 degrees of phase error in the field radiated by the patches. For the array considered here, this limits the relative sidelobe level to approximately -25 dB.<>