Near-field to far-field transformation by using antenna array factor

When radiation pattern of an antenna or scattering pattern of radar cross-section (RCS) is measured, its characteristics is usually evaluated in the far-field area. In this case, it is measured in the radio anechoic chamber to reduce unnecessary reflected wave and deviate from the condition of the far-field according to the size or the measuring frequency. On the other hand, it is well known method such as compact-range or the transformation processing method which transform pick-up data from the near-field to the far-field. This paper presents simple method and measurement results of this far-field transformation by using the idea of array-factor for prediction far-field from the near-field data of antenna and RCS in cylindrical scanning system.