Array near field focusing

Antenna arrays are normally characterized in terms of their far field radiation patterns, beam width and directive gain. However, for some applications the array is focused in the near field. The focus size is determined in terms of the near field properties of the array. The focusing is done through adjusting the phase of the elements of the array. The simulations are done using the method of moments (MoM). Two methods for adjusting the phase are compared. The focusing techniques analyzed here have several applications including imaging apertures, for which high spatial resolution is of great importance.