以移动测绘平台定位定姿为应用背景，基于PPP模糊度固定技术和扩展卡尔曼滤波方法，深入研究模糊度固定解精密单点定位(PPP)与惯性导航系统(INS)进行紧组合的理论与方法。本项目的主要研究内容有：(1)模糊度固定解PPP/INS紧组合扩展卡尔曼滤波器构建；(2)借助INS短期导航精度高的优势，辅助PPP模糊度固定并实现瞬时重新固定；(3)适用于PPP/INS紧组合的前后向平滑算法；(4)模糊度固定解PPP/INS紧组合成果的质量检核方法。通过以上研究解决模糊度固定解PPP/INS紧组合中所面临的一系列理论难题，将丰富PPP模糊度固定及组合导航等相关理论。与常用的DGNSS/INS组合相比，新组合无需地面基准站支持、作业简单且成本低；与模糊度浮点解PPP/INS组合相比，新组合收敛时间短且能获取稳定的厘米级定位精度。

With applications to positioning and attitude determination of the mobile mapping platforms, this project will utilize the PPP (Precise Point Positioning) ambiguity fixing technology and the Extended Kalman Filter (EKF) approach to study the theories and methods of tight integration of ambiguity-fixed PPP and INS (Inertial Navigation System). Specially, this project will mainly focus on the following problems: (1) the design of EKF for tight integration of ambiguity-fixed PPP/INS; (2) PPP ambiguity fixing and instantaneously re-fixing aided by INS; (3) the forward backward smoother with application to tight integration of PPP/INS; (4) internal quality assurance methods for the results of tight integration of ambiguity-fixed PPP/INS. Through the above study, this project will solve several theory problems of the new integration and enrich the related theories about PPP ambiguity fixing, integrated navigation and so on. Additionally, compared with the conventional DGNSS/INS integration, the new integration has no requirement of base stations and reduces the complexity and cost of the system; and compared with the ambiguity-float PPP/INS integration, the new integration has short convergence time and could acquire stable centimeter-level positioning accuracy.