Systmem Design And Algorithm Research Forindoor Integrated Navigation

With the rapid development of navigation technology,the demand for positioning is enhanced.Under the complex indoor environment,the positioning information from a single source can no longer meet the requirements of high-precision positioning.Therefore,the navigation and positioning technology of multi-source information fusion has become the inevitable trend.In this paper,it takes the indoor navigation system integrated of INS/CSS as the research object.It includes the principle of INS&CSS,IMU design,and inertial navigation experiment based on INS.The design of CSS star selection algorithm,extended Kalman filter fusion algorithm are also studied.The specific work is shown as follows:First of all,the basic principle of INS and the wireless positioning technology based on CSS are analyzed and studied.For INS,this paper analyzes how to solve the posture and position of carrier by inertial information,geomagnetic information,velocity and position information of carrier based on navigation coordinate system principle and posture angle definition.It shows the urgency of different types of information fusion and the challenges.As for the CSS positioning technology,the CSS information transmission carrier and its unique ranging method are studied.Finally,the CSS communication environment and its detailed indoor positioning process are explained in detail.Then,the research and design based on INS of indoor positioning system are started.By reckoning algorithm for pedestrian navigation,the pulse counting velocimetry algorithm to acquire the carrier displacement is proposed.For the posture angle of the carrier,we design and realize the IMU based on MPU9250 multi-axis sensor.The design system takes ARM-LPC1788 as a microprocessor,transplants digital motion processing(DMP)database successfully,and acquires accurate and reliable data by quarternion solution.After that,extension interpolation model is used to optimize the data to eliminate the jitter error and obtain the stable posture value.Since the MPU9250 contains a magnetometer,it can avoid the cumulative error of the heading angle.The designed IMU can collect the accurate posture information of the current carrier in real time,and the measurement deviation is less than 0.1°.It provides a more stable and accurate posture angle reference standard for the PDR algorithm in the inertial navigation system.Through the inertial navigation experimental,it indicates that the average error of the inertial navigation system is 0.2941 m when walking in a straight line.And the average error of zigzag walking is 0.3023 m.Finally,INS-assisted CSS navigation and positioning method research is conducted.Satellite selection method according to the three-sides principle of a triangle is proposed by analysis of CSS NLOS ranging error.The star selection algorithm effectively reduces the impact of the NLOS in the indoor complex environment,and a CSS indoor positioning simulation experiment is conducted.With the analysis of single CSS positioning error,integrated navigation design method of CSS-aided INS is raised.The paper introduces the realization principles and advantages of the CSS-aided INS positioning method exhaustively.It also proposes the combination of positioning result between INS and CSS by Extended Kalman filter,which could get more stable and accurate positioning results.We carried out the comparison experiments of three kinds positioning method in the underground garage of Hangzhou DianZi University library and the practical application experiment of navigation and positioning in the underground garage.The results show that the average positioning error of the proposed CSS-aided INS positioning system is less than 1 meter,and the performance is 50% better than other two single location methods.