Research On Multi-source Navigation Signal Source Simulation And Interference Modeling Technolog

In modern navigation systems,the integrated navigation of inertial navigation and satellite navigation has received widespread attention due to its strong autonomy and high positioning accuracy.To verify the accuracy of traditional navigation algorithms,the algorithm needs to be loaded into the target carrier for actual testing.The accuracy of this method is reliable,but the upgrade and performance improvement of the navigation algorithm need to be measured,which leads to the increasing research time of navigation algorithm and severely inhibit the development of navigation systems.In order to solve this problem,this thesis analyzes and models the signal of multi-sensor information sources in different environments,and establishes a sensor information source database and a noise model database.The specific work is as follows:(1)Research the mathematical model of GPS intermediate frequency signal and error in the propagation process,based on the software platform to realize the generation of GPS satellite C/A code,navigation message and digital intermediate frequency signal,in-depth discussion of various GPS jamming signals,according to the Monte Carlo simulation model,using the bit error rate as an evaluation index to evaluate the influence of suppressive interference on the communication link.(2)Study the generation mechanism and components of the random drift of inertial sensors,identify the collected sensor data by the Allan variance method and the modified Allan variance method to obtain the coefficients of each error term,and compare the identification effects of the two methods on random drift;After the random drift preprocessing,the model is ordered by the criterion and the criterion,and the time series model of the output data of the inertial sensor is obtained.(3)In order to collect the random drift data of the inertial sensor,the multi-channel highprecision analog-to-digital conversion chip ADS1256 is used as the core chip,and the STM32F103C8T6 is the main control chip to build the inertial sensor data acquisition system to complete the inertial measurement unit P1-IMU-01 G data collection work.(4)Considering the problems of the inconvenience of use and the difficulty in obtaining the flight trajectory of the carrier,a scheme of generating inertial navigation signal source using semi-physical simulation is proposed,and the simulation carrier is simulated.Through the strapdown inertial navigation inversion algorithm,the ideal output information of the gyroscope and accelerometer corresponding to the trajectory point is calculated inversely,and the random error model of the real inertial measurement unit is superimposed to realize th e simulation of the real inertial sensor signal source.