Experimental study on the refinement detection at the bottom of foundation pit used by GPR in the strong interference environment

Abstract

Due to the refraction of the detection environment and conditions, the electromagnetic waves emitted by the ground penetrating radar are susceptible to interference from external factors. The received reflected waves often have the characteristics of “weak signals and strong interference”, resulting in low sensitivity and low signal-to-noise in the collected data. Resolution tolerances cause difficulties in data interpretation. Based on the uniqueness characteristics of spectral response for the single medium, and the differences of energy intensity between effective signal and interference signal, the spectrum energy intensity analysis is introduced into signal processing in this article, the spectral response feature of different target mediums have been extract from the signal of radar reflected wave, the spectral energy strength about the underground target medium has been calculated, and the geological distribution feature of underground soil has been inversed according to three-dimensional reconstruction technology in further. It showed that this data processing method proposed in this article can remove interference and preserve effective signal which even weak and deep at the same time by the detection and application effect in the strong interference environment at the bottom of construction foundation pit, the interpretation accuracy of ground penetrating radar had improved and the purpose of refinement data processing had achieved.