| Irn recent years,various types of geological disasters have occurred frequently,which has brought huge economic losses and casualties to China.The landslide disasters with the largest proportion are the most widely distributed and the damage is very serious.Therefore,monitoring the landslide is very practical.The monitoring principle of landslide monitoring is based on the dynamic monitoring of the displacement of the landslide body to grasp the landslide sliding situation in real time,and then use these sliding conditions as the prediction basis for landslide disasters.Although there are many methods for landslide monitoring,these methods cannot meet the requirements of high precision,low cost and high practicability at the same time.Therefore,these methods are difficult to be widely used in real-time monitoring of landslide hazards.Through comparative analysis of landslide monitoring methods,it can be found that if the GPS landslide monitoring method is studied in depth,these three requirements can be met.This thesis studies the development history of GPS landslide monitoring technology at home and abroad and sumrnarizes the advantages and disadvantages of these GPS landslide monitoring technologies.After comparing the advantages and disadvantages of these technologies,it is found that these technologies are also difficult to meet these three requirements at the same time.In order to achieve this goal,this thesis studies RTK(Real-time kinematic)real-time dynamic carrier phase difference technology,a new commonly used satellite positioning measurement method.Therefore,the research content of this thesis is mainly the three key techniques of solving the integer ambiguity in the RTK carrier phase difference technology,the GPS baseline solution and the data link of the GPS differential system.Solving the integer ambiguity this thesis studies the classical LAMBDA algorithm and the improved particle swami optimization algoritlim,and makes some comparative experiments on the two.After correcting the integer ambiguity,the GPS baseline solution and attitude measurement principle are studied and the single-frequency GPS attitude detector is developed.Finally,the single-frequency GPS attitude detector is used as the reference station and rover in the RTK carrier phase difference technology to design a data link of the GPS differential system.The basic principle of the GPS landslide monitoring system studied in this thesis is to form a short baseline measurement method by placing the reference station and the rover in the RTK carrier phase difference technology in the landslide monitoring area,because the two observation stations are in the same monitoring area.The common en*or between them is the same,and if the difference between the two is done,these common errors can be eliminated to achieve high measurement accuracy of millimeters.In order to meet the requirements of high practicability,this thesis designs a data transmission system based on LoRa and GPRS.The system uses LoRa and GPRS data transmission modules to enable the observation data of the monitoring site to be transmitted to the monitoring center in time,thereby improving the real-time performance of landslide monitoring.It can be seen that the GPS landslide monitoring system and data transmission system designed in this thesis meet the requirements of high precision and low cost by using the short-baseline measurement forai of single-frequency GPS spectroscopy.On the other hand,the real-time monitoring of the monitoring system is realized by LoRa and GPRS modules,which meets the requirements of high practicability,so the landslide monitoring system that can theoretically meet these three requirements can be widely used in landslide monitoring,and this thesis also innovatively proposes an improved particle swarm optimization algorithm.The integer ambiguity is solved,and the algorithn can improve the efficiency of the integer ambiguity to better ensure the real-time monitoring of the landslide monitoring system. |
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