A Theoretical Description of the IsoFilter Rejection Curve
Author: Doren W. Hess
Publication: EuCAP 2011
Copyright Owner: IEEE
The early work with the IsoFilterTM
technique demonstrated that the radiation emanating from the aperture of a horn,
located several wavelengths above a ground plane, could be separated from the radiation due to the sidelobe and backlobe
illumination of the ground plane itself. The success of this demonstration encouraged us to pursue further the question of
how well the IsoFilterTM
technique worked to suppress other types of secondary signals such as signals coming from
other elements of an array antenna or another individual first-order primary radiator nearby.  In the process of
evaluating the goodness of the secondary signal suppression we devised a method for identifying the locations and
strengths of an antenna's radiation sources that is an alternative to conventional back-projection. The alternative method
utilizes the antenna's far-field measured radiation pattern and successive spherical modal analyses to ascertain the relative
strength of the antenna's sources that give rise to its far field. We believe that this alternative technique has applicability to
the general problem of antenna diagnostics. Please see the Figure below for an example of an IsoFilterTM rejection curve. 
You have requested a Reprint of an IEEE Paper
Copyright 2011 IEEE. Reprinted from EuCAP 2011 Conference.
This material is posted here with permission of the IEEE. Such permission of the IEEE does not in any way imply IEEE endorsement of any of NSI-MI Technologies' products or services. Internal or personal use of this material is permitted. However, permission to reprint/republish this material for advertising or promotional purposes or for creating new collective works for resale or redistribution must be obtained from the IEEE by writing to email@example.com.
By choosing to view this document, you agree to all provisions of the copyright laws protecting it.