Radome Diagnostics—Source Reconstruction of Phase Objects With an Equivalent Currents Approach

Abstract

Radome diagnostics are acquired in the design process, the delivery control, and in performance verication of repaired and newly developed radomes. A measured near or far eld may indicate deviations, e.g., increased side-lobe levels, but the origin of the aws are not revealed. In this paper, radome diagnostics are performed by visualizing the equivalent surface currents on the 3D-radome body, illuminated from the inside. Three dierent far-eld measurement series at 10 GHz are employed. The measured far eld is related to the equivalent surface currents on the radome surface by using a surface integral representation. In addition, a surface integral equation is employed to ensure that the sources are located inside the radome. Phase shifts, insertion phase delays (IPD), caused by patches of dielectric tape attached to the radome surface, are localized. Specically, patches of various edge sizes (0.5 − 2.0 wavelengths), and with the smallest thickness corresponding to a phase shift of a couple of degrees are imaged.

Source Reconstruction by Far-Field Data for Imaging of Defects in Frequency Selective Radomes

“…2. In this paper, we only give a short outline of the algorithm and some key implementation aspects, since the algorithm is thoroughly described in previous works, see [12,14]. The electric surface integral equation (EFIE) [7] …”

“…1a, is set to 2200 m. Employing larger radii do not change the results signicantly. More details, parameter choices of the MoM code, and discussions about the regularization parameter are found in [14].…”

“…Especially, radiation contributions from leaky cables are analyzed in [16], antennas are diagnosed in [1,8,9,11,17], and equivalent currents on a base station antenna are studied in [5]. A more detailed background of source reconstruction methods is found in [14]. This paper revisits the reconstruction algorithm described in [12,14] in order to investigate if defects on an FSS radome can be imaged.…”

“…A more detailed background of source reconstruction methods is found in [14]. This paper revisits the reconstruction algorithm described in [12,14] in order to investigate if defects on an FSS radome can be imaged. In Sec.…”

“…In this paper, we focus on the rst two measurement series illuminating the top. The last two series are utilized as reference measurements to set the regularization parameter as described in [14]. Moreover, in the last series, a dielectric patch was attached to the radome surface, and the reconstruction of this patch was employed to verify the absolute position of the radome in the chamber.…”