Monitoring of St. Sophia Cathedral interior using Ka-band Ground Based Noise Waveform SAR

This work is devoted to measurement of shifts inside an old Cathedral using a Ka-band ground based noise waveform SAR (GB NW-SAR). Design of this SAR is based upon synthetic aperture antennas and noise radar technology. The system is intended for small shifts measurement at large objects using differential interferometry technique and it can be used for detection of pre-catastrophic changes. In current experiments, GB NW-SAR was used in monostatic regime with CW signals. Resolution of the GB NW-SAR was ~ 30 cm both in range and azimuth. The SAR has been placed inside the St. Sophia Cathedral in Kiev and used for shifts detection in sealing of the building covered with ancient frescos and mosaics. Precision of shifts measurements up to 0.1 mm has been shown. Influences of reflections inside the building have been analyzed. High stability of the object of interest has been shown.