Multi-point Surface Deformation Monitoring Method And Its Performance Study

Real-time monitoring and early warning of geological hazards and engineering buildings can effectively protect people’s lives and property,of which the monitoring of deformation state is the main means of monitoring and early warning.Radar displacement measurement can monitor a number of monitoring points on the target surface at the same time,simple,direct and accurate monitoring of object surface deformation,with the advantages of all-weather,high dynamic,high precision,etc.In the traditional radar deformation monitoring,there is a conflict between the range of phase method displacement measurement and measurement accuracy,and in the traditional measurement of the deformation object abstracted as a rigid body and replaced by a point,can not obtain detailed deformation information,while the interference of environmental clutter will also greatly reduce the reliability of deformation monitoring.In thesis,to address these problems,the linear frequency modulated continuous wave（LFMCW）based displacement measurement algorithm with high accuracy is investigated to address these problems,and the four main points are as follows.1.Aiming at the key problem of small displacement measurement range due to phase ambiguity in this algorithm,the range extension technique using multi-scale measurement method is studied,which can achieve the extension of displacement measurement range while ensuring the measurement accuracy,and the various problems affecting its measurement accuracy are studied.2.For the problem of multi-target distinction,this thesis investigates the multi-target distinction method based on time-sharing measurement method and simultaneous measurement method,which can realize the distinction of multi-targets without affecting the accuracy of single-point displacement measurement.3.For the problem of environmental clutter interference,this thesis investigates the polarization reversal clutter suppression method,which can effectively suppress environmental clutter.4.Develop radar deformation instrument prototype,complete hardware design and software implementation.After simulation and experimental verification,the range extension technique of multi-scale measurement method proposed in thesis solves the phase ambiguity problem and realizes the displacement monitoring effect with high precision and large range.Combining the multi-target differentiation method based on time-sharing measurement method and simultaneous measurement method and the environmental clutter suppression method based on polarization twist,the high-precision displacement monitoring of multiple targets can be realized.