容错组合导航系统联邦滤波器设计中的信息同步

On Signal Synchronization in Designing Federated Filter for Fault-Tolerant Integrated Navigation System

探讨了各子滤波器同步时间差及同步滤波信息的计算。仿真计算结果表明，经同步处理后，融合精度与理想情况即所有子滤波器完全同步时的精度十分接近。

Carlson in 1988[4] assumed that, in the federated filter for fault - tolerant integrated navigation systems, all local filters worked synchronously and handed in their outputs to the master filter just at the same fusion time. In practical applications the design of such a fede-ated filter is impossible, because each local filter operates with its own measurement updating rate.To meet the need of practical applications, we propose a synchronization algorithm that includes the calculation of the time difference between fusing and filtering for each local filter, and the calculation of the time updating needed for taking such time difference into consideration.We designed a federated filter for a fault - tolerant integrated navigation system composed of the following subsystems: a ring Laser gyro strapdown inertial navigation system, a GPS C/A cord receiver, a Doppler radar, an air data system, a magnetometer, and a vertical gyro. Computer simulation of such a filter shows that our synchronization algorithm is effective.