A finite passive periodic antenna array, or Frequency Selective Surface, exhibits a phenomenon that an infinite passive array, or FSS, does not. Namely, surface waves which propagate along the periodic array structure may be induced in the array at frequencies below the resonant frequency of the array. These surface waves may radiate energy when they reach the ends or other discontinuities in the finite array and may therefore increase the Radar Cross Section of the array.
Surface waves on arrays that are periodic and infinite in one dimension will be studied. A number of array geometries will be investigated, including planar, corner, multilayer, curved, and cylindrical arrays. Several techniques to reduce the backscat-tered field from these surface waves will be studied. These techniques include resis¬tive loading along the entire array, resistive loading at the points of discontinuity, and special shaping of the array to shed the surface wave energy. Numerous calculated examples will be presented, and several examples of measured results will be given to verify the calculated results.