Translated Spherical Wave Expansion (TSWE) is an advanced Near-Field/Far-Field (NF/FF) transformation tool which allows to reduce the number of samples in case of offset spherical NF measurements.

TSWE is based on the modification of the Spherical Wave Functions which are properly redefined in a new reference system located on the AUT (not on the center of the measurement sphere).

How does it work?
  • If the DUT is offset with respect to the center of the measurement sphere more samples are needed to correctly represent the DUT (bigger minimum sphere and more rapidly varying phase).
  • The information associated to the DUT should not depend on its location since the radiator itself is unchanged.
  • The additional samples needed in case of offset measurements can be strongly reduced using TSWE.