Reprint:
https://www.cnblogs.com/zhoug2020/p/8376509.html
https://zhuanlan.zhihu.com/p/25598462 (know almost classical Kalman filter paper)
https://blog.csdn.net/woaizgw/article/details/73648578 (PPT formula which is good)
The meaning of each parameter of the Kalman filter equations five
Kalman filtering and smoothing understanding of the relationship between Kalman
Common signal smoothing method