前后向平滑算法在精密单点定位/INS紧组合数据后处理中的应用  

Forward-backward-smoothing algorithm with application to tightly coupled PPP/INS data post-processing

作　　者：刘帅[1] 孙付平[1] 李海峰[1] 张伦东 

机构地区：[1]信息工程大学导航与空天目标工程学院,郑州450001

出　　处：《中国惯性技术学报》2015年第1期85-91,共7页Journal of Chinese Inertial Technology

基　　金：国家自然科学基金(41374027)

摘　　要：精密单点定位技术只需单台双频GNSS接收机就能实现分米到厘米级定位精度,将其与INS进行组合可以广泛应用于测量领域。但当GNSS信号被完全遮挡时,只能依赖纯惯性导航工作模式,而当重新捕获GNSS信号时,又需要一定时间才能使精密单点定位重新收敛到理想精度。针对以上问题,提出了一种适用于精密单点定位/INS紧组合的前后向平滑算法来同时提高GNSS信号完全遮挡段和重新收敛段的导航精度,详细推导了该算法的数学模型。对实测的跑车实验数据后处理表明:前后向平滑算法能有效提高精密单点定位/INS紧组合导航精度;对60 s完全遮挡段的位置误差统计表明,前向和后向滤波的三维位置误差RMS分别为44.46 cm和10.81 cm,平滑后改善到了10.47 cm。Precise point positioning (PPP) techniques can achieve decimeter-to centimeter-level accuracy only by using one dual-frequency GNSS receiver, and hence the integration of PPP with INS can be widely used in survey fields. However when GNSS signals are totally obstructed, the PPP/INS system can only rely on INS solutions; and when GNSS signals are reacquired, the PPP/INS system can only re-convergence to ideal positioning accuracy by taking considerable time. To solve this problem, a forward-backward-smoothing (FBS) algorithm suitable for tightly-coupled PPP/INS integration is proposed. The mathematical model for implementing the FBS algorithm is derived. The post-processing results of field test data indicate that the FBS algorithm can effectively improve the PPP/INS navigation accuracy. The statistics of the positioning error during 60 s total-blockage demonstrate that the 3D positioning error RMSs of forward and backward filters are 44.46 cm and 10.81 cm, respectively; and they are improved to 10.47 cm after using the smoothing algorithm. ©, 2015, Editorial Department of Journal of Chinese Inertial Technology. All right reserved.

关 键 词：精密单点定位 惯性导航系统 紧组合 前后向平滑 定位测姿 

分 类 号：U666.1[交通运输工程—船舶及航道工程]