I assume that you have measured something that you did not expect. We
have been working on theoretical analysis of power and ground plane
behavior. What kind of field distribution have you observed?
Can you describe your structure? What geometries and materials are
involved? Are there holes or cuts in the planes? What kind of
distortion in the field distribution do the apertures cause?
-- Bob Techentin firstname.lastname@example.org Mayo Foundation (507) 284-2702 Rochester MN, 55905 USA http://www.mayo.edu/sppdg/sppdg_home_page.html