给出了一种交互多模型(interacting multiple model,IMM)算法中 Markov 转移概率矩阵在线修正的方法,并将平方根容积卡尔曼滤波器(square-root cubature Kalman filter,SRCKF)引入到 IMM 算法中,提出一种时变转移概率的机动目标跟踪 IMM-SRCKF 算法。该算法利用当前量测中包含的模式信息,对 IMM 算法中的转移概率矩阵进行实时递推估计,避免了常规 IMM 算法中转移概率先验确定的困难,提高了模型切换速度和跟踪精度;同时,SRCKF 以目标状态协方差的平方根进行迭代更新,确保了滤波过程中协方差矩阵的对称性和半正定性,改善了数值精度和稳定性。仿真实验结果表明,该算法对机动目标的跟踪性能优于常规的 IMM 及 IMM-CKF算法。
An on-line updating method of Markov transition probability for the interacting multiple model (IMM)algorithm is proposed,and the square-root cubature Kalman filter(SRCKF)is introduced into IMM,so a novel time-varying Markov transition IMM-SRCKF algorithm is obtained.Using real-time recursive estimation method based on the system mode information implicit in the current measurements,the proposed algorithm ef-fectively avoids the problem of prior determination of the Markov transition probability matrix in traditional IMM.Furthermore,SRCKF propagates the square root of the covariance in filter interaction so that it guaran-tees the symmetry and positive semi-definiteness of the covariance matrix and greatly improves the numerical stability and numerical accuracy.Simulation results show that the proposed algorithm has better tracking per-formance and higher efficiency compared with the conventional IMM and IMM-CKF.