Simulation of locating buried objects via fringe pattern-based measurements in an optical fiber sensor-integrated continuous-wave ground-penetrating radar system

摘要

A new ground-penetrating radar system that can determine the depth and position of a buried metal cylinder, which is the combination of an optical fiber sensor (OFS), continuous-wave transmitter, and optical communication link, is proposed and simulated in the MATLAB and Optiwave program packages. Employing an optical sensor instead of a standard radio frequency (RF) receiver offers the advantage of preventing electromagnetic interference along the sensor's main unit cable and lower amplification noise. In this paper, the electric field distribution at the OFS due to reflections from the soil surface and the buried object is obtained mathematically using Green's function. The OFS's detected electric signal is then simulated. The effects of the cylinder's depth and the RF transmitter frequency are observed. The plots of the OFS output voltages vs. the x-axis distance to the burial point display interference fringe patterns. The position and the depth of the cylinder are determined using the characteristics of these patterns. It is estimated that the burial depth can be ascertained with a maximum 5-cm error for a 1-GHz transmitter frequency.