The Kalman filtering (KF) is widely used in the low-cost MEMS-SINS/GPS integrated navigation system. In such a system, the quaternion method is usually used to calculate the attitude angles, and then the attitude angular error correction is made by the periodic Kalman filtering. This will result in two different effects. One is the produced angular divergence if the filtering cycle is long; another is the increased complexity and the affected real-time effects if the filtering cycle is short. To trade off the filtering performance and the real-time effect, the KPCA (Kernel principal component analysis) based KF is proposed in this...