Design And Implementation Of Seismic Exploration And Positioning System Based On RSSI-LQI

Seismic exploration is one of the most important exploration methods in underground resource exploration.The positioning system for seismic exploration usually uses the GPS global positioning system.The GPS positioning system has the characteristics of high accuracy and strong anti-interference ability,but it may not receive GPS signals normally in a harsh environment.At present,the common positioning assistance system usually uses a ranging algorithm based on Received Signal Strength Indication(RSSI),but the ranging algorithm based on RSSI has the disadvantages of low accuracy and susceptibility to the environment.The improved weighted triangular centroid algorithm based on Received Signal Strength Indication-Link Quality Indicator(RSSI-LQI)is used as an auxiliary positioning method for the seismic exploration system and implements the positioning system to improve the reliability of seismic explorationThis thesis improves the ranging algorithm based on RSSI for two stages of positioning:(1)In the ranging stage,this thesis introduces the link quality of distance,which is the influencing factor of distance,analyzes the fading curves of RSSI and Link Quality Indicator(LQI)through the actual ranging experiment results,and fits the curve using a segmented method.In the positioning process,data measurement is the key to positioning.If accurate data support cannot be given,it will affect the subsequent positioning work.This article analyzes in detail the factors that affect the measurement errors,including the impact of hardware and environmental factors.Therefore,in data measurement,how to select the hardware correctly and reduce the impact of environmental and human factors is particularly important.Since the positioning system proposed in this thesis is ultimately used outdoors,for unknown nodes,the more complex the surrounding environment,the greater the change in the collected RSSI and LQI data values,so this thesis uses Kalman filter algorithm and mean filter algorithm.Combined way to correct the data values of RSSI and LQI collected by distance measurement to improve the accuracy of distance measurement;(2)In the positioning stage,in order to prevent the data frame from falling into an endless loop when experiencing multi-hops,the distance between the unknown node and the beacon node is too large,resulting in invalid ranging,etc.In this thesis,data such as distance sum,MAC address and hop value are added to the design of the data frame Structure.In addition,the positioning algorithm itself will also cause errors.At present,the common node coordinate calculation method of the positioning system is to use the weighted triangular centroid algorithm for positioning.However,when using the weighted triangular centroid algorithm for positioning,due to the error of the distance measurement,the weighted triangular centroid algorithm The three centroid circles may not intersect,which results in the weighted triangle centroid algorithm unable to locate,and the positioning accuracy of the weighted triangle centroid algorithm is low.Therefore,this thesis improves the weighted triangular centroid algorithm,proposes new weights,improves the positioning accuracy,and enables unknown nodes to locate normally when the error is too large.The MATLAB software compares the improved weighted triangular centroid algorithm based on RSSI-LQI proposed in this thesis with the other three positioning algorithms.The simulation results show that the proposed positioning algorithm is more accurate than the other three positioning algorithms.highFinally,based on the improved weighted triangular centroid algorithm based on RSSI-LQI,the design of the seismic exploration positioning system is completed,and the software and hardware platform of the positioning system is built.In the outdoor environment,the positioning experiment based on RSSI-based positioning system,LQI-based positioning system and the positioning system designed in this thesis were conducted.The experimental results show that the RSSI-LQI-based seismic exploration and positioning system designed in this thesis is more accurate than the other two positioning systems When the node communication radius is 20m,the positioning accuracy is about 1.7m,which provides the entire seismic exploration system.A strong guarantee.