Abstract: The algorithm of UKF_IMM has better tracking performance for arbitrary nonlinear systems under the Gaussian conditions.But serious errors can arise when it is used in nonlinear nongaussian systems.PF_IMM is effective in nonlinearity and nongaussianity，however，it has a large computation.In existing literature on combining IMM and PF or UKF techniques to tackle difficult target maneuvers，a PF or UKF is usually used in every model.In comparison，IUS_IMM which uses a PF in the 2DTR model and UKF in the remaining models is put forward.Simulation results show that IUS_IMM has superior performance than UKF_IMM when maneuvering target is under high turn frequency circumstances.

摘要： UKF_IMM算法对任何非线性高斯系统都有较好的跟踪性能，但在用于强非线性、非高斯系统时将产生极大的误差。PF_IMM算法适用于任何非线性非高斯系统，但它因计算量很大而导致实时性太差。在现有的基于PF或UKF的IMM滤波算法中，PF或UKF通常被用于每一个模型，基于此，提出了IUS_IMM算法，即在转弯模型中使用标准粒子滤波器（SPF），在其他模型中用UKF滤波器，仿真结果表明，对于转弯频率高的机动目标，IUS_IMM的性能要好于UKF_IMM算法。