GPS/惯性组合方式讨论与导航精度分析

DISCUSSION ON THE INTEGRATION APPROACHES AND NAVIGATION PERFORMANCE OF INTEGRATED GPS / INERTIAL NAVIGATION SYSTEMS

本文讨论GPS/惯性组合两种方式的优缺点。并以GPS伪距和伪距率与惯导组合为例,按GPS测量误差的不同,以及使用差分机等情况,仿真计算了机载使用的组合导航性能,进行了详细的精度分析。结果表明,这种组合的导航精度比GPS和惯导各自的导航精度高。在采用差分GPS机与惯导组合后,位置误差将进一步减少,使组合导航具有开辟例如飞机进场着陆等新的使用领域的可能性。

There are two basic approaches to integrate the Global Positioning System(GPS) with Inertial Navigation System (INS). One approach utilizes the navigation solution of GPS receiver to aid INS. This paper discusses mainly the another approach which utilizes the pseudo range and pseudo range rate measurements of GPS receiver to integrate GRS with INS. It shows that the integrated system pro'vides excellent performance which cannot be achieved by either GPS of ins alone. The improved accuracy is based on the facts that the system uses both position and velocity integration which can complement each other; the system makes the bias of pseudo range measurement observable; comparing with navigation solution of GPS receiver, the system can restrain the effect of GPS Geometric dilution of precision (GDOP) on navigation accuracy. Numerical simulation results are presented to demonstrate the improved performance of the integrated system under different conditions, such as different values of GPS measurement errors, integrating with general GPS or differential GPS.