| Indoor positioning technology is the difficulty of indoor and outdoor continuous and high-precision positioning.In recent years,because indoor positioning technology can provide location information in buildings,it has broad potential commercial application prospects in the fields of safety monitoring,emergency rescue and public location services in large and complex indoor public places,and has become a hot spot of international research.Pseudolite positioning,foot-mounted inertial navigation(FMIN)and pseudolite/FMIN/landmark hybrid positioning on dedicated terminal are effective solutions to achieve indoor and outdoor continuous and high-precision positioning.However,there are a series of technical bottlenecks in these technologies,such as pseudolite anti-multipath in complex indoor environment,irregular path heading correction,pedestrian motion pattern recognition and hybrid positioning mechanism.Study on the pseudolite/FMIN/landmark multi-source hybrid positioning method contributes to improve the usability and accuracy of indoor and outdoor positioning system.It can not only enrich and improve indoor and outdoor multi-source hybrid positioning methods and theories,but also provide technical support for indoor and outdoor multi-source hybrid positioning.By taking the dedicated terminal as the carrier and artificial intelligence method and multi-source hybrid positioning theory as the basic,pseudolite signal electromagnetic compatibility was systematically studied through theoretical calculation,simulation verification,test platform construction,experiment and analysis,as well as pseudolite indoor positioning,foot-mounted inertial navigation heading correction,and the hybrid positioning of indoor and outdoor.The main contributions are as follows:(1)The pulse duty cycle design of pseudolite navigation signal was completed based on the analysis of the navigation signal compatibility of pseudolite,GPS and Beidou.The indoor signal propagation characteristics of pseudolite were excavated from multiple angles,a fitness function based on carrier phase measurement error was constructed,and the pseudolite indoor positioning algorithm based on genetic algorithm framework was proposed.Compared with the positioning results of Doppler difference algorithm and traversal search algorithm,it was found that the positioning error of the proposed algorithm was 0.714 m,which was reduced by71.26% and 77.98% respectively,and has stronger multipath suppression ability;An indoor pseudolite positioning algorithm with weighting factor adjustment was proposed,the experimental results shown that it was able to effectively reduce the dependence of pseudolite positioning accuracy on the state of transmitting antenna.(2)The relationship model between the y-axis angular rate amplitude peak of foot-mounted inertial sensor and zero-velocity phase detection threshold was constructed.A strict pedestrian straight-line walking detection mechanism and a heading constraint method which can work on irregular straight-line paths(non intersecting 90 ° or 45 °)were proposed.On this basis,the enhanced heuristic drift elimination(e HDE)technology was proposed.The experimental results shown that compared with the heuristic drift elimination(HDE)and its improved algorithm,the e HDE method not only improved the zero-velocity phase detection accuracy under different pedestrian at changing walking speed,but also has stronger heading constraint ability on irregular paths with many linear features.(3)Responsible for building a pedestrian multi-source hybrid positioning test platform,focusing on the development of GNSS/pseudolite high-precision positioning module,selecting commercial inertial measurement unit and microprocessor to build a foot-mounted inertial navigation module,and using smartphone as the platform for the development of multi-source hybrid positioning algorithm.The outdoor high-precision positioning and indoor pseudolite original observation output were realized on the GNSS/pseudolite high-precision module.The foot-mounted inertial positioning algorithm was developed in the foot-mounted inertial positioning module,the pseudolite positioning algorithm and multi-source hybrid positioning algorithm were developed in the smartphone.The data interaction protocol between GNSS/pseudolite high-precision positioning module,foot-mounted inertial positioning module and smartphone was designed,which provided a dedicated test platform for pseudolite/foot-mounted inertial navigation/landmark indoor and outdoor hybrid positioning research.(4)A landmark assisted foot-mounted inertial navigation heading error elimination mechanism was established,a foot-mounted inertial navigation assisted pseudolite carrier phase observation error matching positioning was proposed and a pseudolite/FMIN/landmark indoor and outdoor hybrid positioning filtering model was designed.The experimental results shown that the RTK/pseudolite/FMIN/landmark coupled has the highest positioning accuracy and can constrain the heading of foot-mounted inertial navigation to a very close to the real heading.On the 365 meters path from outdoor to the end of indoor corridor,the positioning error of foot-mounted inertial navigation was 7.616 meters,while the positioning error of FMIN/landmark coupled loosely was only 0.876 meters,which was reduced by 88.5%;In the indoor area where the pseudolite was deployed,compared with foot-mounted inertial navigation,the positioning error of pseudolite/FMIN coupled loosely was reduced by56.6%.There are 103 figures,32 tables and 196 references in this dissertation. |
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