Radome diagnostics - source reconstruction of phase objects with an equivalent currents approach

Radome diagnostics are acquired in the design process, the delivery control and in performance verification of repaired and newly developed radomes. A measured near or far field may indicate deviations, e.g., increased side lobe levels, but the origin of the flaws are not revealed. In this paper, radome diagnostic is performed by visualizing equivalent currents on a radome surface. We localize phase shifts, an effective insertion phase delay (IPD), caused by patches of dielectric tape attached to a radome surface. The IPD of one layer tape, 0.15 mm, is detected. Imaging results from three different far-field measurement series at 10 GHz are presented. The measured far field is related to the equivalent surface currents on the radome surface by using a surface integral representation together with the extinction theorem. The problem is solved by a body of revolution method of moment (MoM) code utilizing a singular value decomposition (SVD) for regularization. (Less)