说明：  在船舶航行中，会观测其轨迹，但是一般的观测手段会有很多噪声。引入卡尔曼滤波器后，会消除一部分噪声，提高准确率。
(In ship navigation, its trajectory will be observed, but the general observation means will have a lot of noise. After introducing Kalman filter, a part of the noise will be eliminated and the accuracy will be improved.)