A novel micro-deformation monitoring system for large scale structure

This paper describes a novel remote sensing technique for deformation monitoring. This system consists of two parts: a set of radio beacons and a telemetering receiver. The radio beacons are installed apart on the large structure. These beacons have the same carrier modulated by the same PN codes with different delays that exceed one chip period. The distance between any two PN codes is unique so as to distinguish the beacons from each other. The telemetering receiver receives the mixed signal from all the beacons, and uses de-correlation to recover every beacon´s carrier. Phase detectors measure the phase difference between all other carriers and the reference carrier. The micro-deformation value Δd is proportional to the phase difference Δθ, and then the deformation curve can be drawn out. The simulation result has proved that the technique proposed by this paper is correct.