Restrictions on the field of view for an undersampled 1-D synthetic thinned aperture radiometry

Traditional radio astronomy formulation of the field of view (FOV) applied to a non-Nyquist spatially sampled synthetic thinned aperture radiometers appear to overestimate the FOV. Utilizing the current design of the Hurricane Imaging Radiometer (HIRad) as a baseline instrument, a simple analytical instrument simulator is developed to investigate the different methods of determining the FOV. Analytically, this value is found to be 70deg. However the usable range seems to extend only to 61deg. The presence of aliased grating lobes is easily seen in the synthesized antenna patterns. Beam efficiency plots with threshold levels can be used to determine the reduced FOV. Error analysis is performed utilizing several sample images of Hurricane Katrina.