说明：  扩展kalman滤波在目标跟踪中的应用。给出了一种基于距离的目标跟踪算法Matlab源程序，并附上详细注释，程序调试通过，可直接运行。
(Extended kalman filter in target tracking. Gives a target distance based tracking algorithm Matlab source, along with detailed notes, debugging through, it can be directly run.)