IMAGING OF SCATTERERS ON MICROWAVE ANTENNA TEST RANGES

A circular synthetic aperture imaging technique for evaluating the per formance of antenna far-field test ranges is presented. Using multifre quency data, the fields incident on the region occupied by the scannin g antenna are used to produce microwave images showing the distributio n and level of scattering artifacts on the test site, Results are pres ented for S- and X-band ranges on a large outdoor antenna measurement facility. Various primary scatterers are identified, together with a s ource of secondary illumination of scattering objects.