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1.
Particle filters have been widely used in nonlinear/nonGaussian Bayesian state estimation problems.However,efficient distribution of the limited number of particles in state space remains a critical issue in designing a particle filter.A simplified unscented particle filter(SUPF) is presented,where particles are drawn partly from the transition prior density(TPD) and partly from the Gaussian approximate posterior density(GAPD) obtained by a unscented Kalman filter.The ratio of the number of particles drawn from TPD to the number of particles drawn from GAPD is adaptively determined by the maximum likelihood ratio(MLR).The MLR is defined to measure how well the particles,drawn from the TPD,match the likelihood model.It is shown that the particle set generated by this sampling strategy is more close to the significant region in state space and tends to yield more accurate results.Simulation results demonstrate that the versatility and estimation accuracy of SUPF exceed that of standard particle filter,extended Kalman particle filter and unscented particle filter.  相似文献   

2.
Cubature粒子滤波   总被引:6,自引:1,他引:5  
非线性非高斯下后验概率密度函数解析值无法获得,需设计合理的重要性密度函数进行逼近。传统粒子滤波(particle filter, PF)直接采用未含最新量测信息的状态转移先验分布函数作为重要性密度函数来逼近后验概率密度函数。针对PF缺乏量测信息的问题,提出一种基于Cubature卡尔曼滤波(Cubature Kalman filter, CKF)重采样的Cubature粒子滤波新算法(Cubature particle filter, CPF)。该算法在先验分布更新阶段融入了最新的观测数据,通过CKF设计重要性密度函数,使其更加接近系统状态后验概率密度。仿真表明CPF估计精度高于PF和扩展卡尔曼滤波(extended particle filter, EPF),与无轨迹粒子滤波(unscented particle filter, UPF)相比,其精度相当,但算法运行时间降低了约20%。  相似文献   

3.
粒子滤波是指利用Monte Carlo仿真方法处理递推估计问题的非线性滤波算法,这种方法不受模型线性和Gauss假设的约束,是一种处理非线性非高斯动态系统状态估计的有效算法。在粒子滤波的基础上融合扩展卡尔曼滤波(EKF)算法,融合后的新算法在计算提议概率密度分布时,粒子的产生充分考虑当前时刻的量测,使得粒子的分布更加接近状态的后验概率分布。仿真结果表明,该算法对机动目标有更好的跟踪效果。  相似文献   

4.
混杂系统粒子滤波混合状态估计及故障诊断算法   总被引:1,自引:0,他引:1  
混杂系统同时包含连续动态特性和离散动态特性,并且两种动态相互作用,使其故障诊断变得更加困难。针对此问题,提出了一种混合系统粒子滤波混合状态估计及故障诊断算法,提高了现有方法的适用范围和诊断效率。针对混杂系统受控迁移、自治迁移和随机迁移等特点,首先利用随机混杂自动机对系统离散状态(包括故障)和连续状态进行统一建模,重点对现有基于扩展卡尔曼粒子滤波的连续估计算法进行改进,支持利用在线监测数据来估计混杂系统各类迁移产生的各种离散和连续状态,最后根据离散状态估计结果快速实现故障诊断。通过对典型非线性混杂系统的故障诊断,证明了该方法的有效性。  相似文献   

5.
一种补偿的扩展KALMAN粒子滤波   总被引:1,自引:0,他引:1  
设计合适的重要性概率密度函数是粒子滤波中的一个重要问题.首先分析了扩展Kalman滤波器的线性化误差,然后加入调节因子,采用补偿的方法减小线性化误差,并用此方法获取粒子滤波中的重要性概率密度函数,同时该概率密度函数参考了最新的观测量,因此提议分布产生的粒子更能反映系统状态的后验概率分布.实验结果表明新算法的估计性能优于标准粒子滤波和Kalman粒子滤波,与Unscented Patticle Filter相比,新算法降低了计算复杂度.  相似文献   

6.
In order to resolve the state estimation problem of nonlinear/non-Gaussian systems,a new kind of quadrature Kalman particle filter (QKPF) is proposed.In this new algorithm,quadrature Kalman filter (QKF) is used for generating the importance density function.It linearizes the nonlinear functions using statistical linear regression method through a set of GaussianHermite quadrature points.It need not compute the Jacobian matrix and is easy to be implemented.Moreover,the importantce density function integrates the latest measurements into system state transition density,so the approximation to the system posterior density is improved.The theoretical analysis and experimental results show that,compared with the unscented partcle filter (UPF),the estimation accuracy of the new particle filter is improved almost by 18%,and its calculation cost is decreased a little.So,QKPF is an effective nonlinear filtering algorithm.  相似文献   

7.
An adaptive unscented Kalman filter (AUKF) and an augmented state method are employed to estimate the timevarying parameters and states of a kind of nonlinear high-speed objects. A strong tracking filter is employed to improve the tracking ability and robustness of unscented Kalman filter (UKF) when the process noise is inaccuracy, and wavelet transform is used to improve the estimate accuracy by the variance of measurement noise. An augmented square-root framework is utilized to improve the numerical stability and accuracy of UKF. Monte Carlo simulations and applications in the rapid trajectory estimation of hypersonic artillery shells confirm the effectiveness of the proposed method.  相似文献   

8.
Study of nonlinear filter methods: particle filter   总被引:1,自引:0,他引:1  
1.INTRODUCTIONExtended Kalmanfilter(EKF)is probably the most com-mon and popular tool to deal with nonlinear esti mationproblems.It is based on andli mited by model linearizationand Gauss hypothesis.EKF might cause more errors forthose nonlinear systems while esti mating systemstate andits variance.Moreover the linearization maylead to diver-gence of filtering process.The paper introduces a newap-proachto opti mal nonlinear filtering.It is applied to thenonlinear non-Gauss problem.It …  相似文献   

9.
A novel particle filter bandwidth adaption for kernel particle filter (BAKPF) is proposed. Selection of the kernel bandwidth is a critical issue in kernel density estimation (KDE). The plug-in method is adopted to get the global fixed bandwidth by optimizing the asymptotic mean integrated squared error (AMISE) firstly. Then, particle-driven bandwidth selection is invoked in the KDE. To get a more effective allocation of the particles, the KDE with adap- tive bandwidth in the BAKPF is used to approximate the posterior probability density function (PDF) by moving particles toward the posterior. A closed-form expression of the true distribution is given. The simulation results show that the proposed BAKPF performs better than the standard particle filter (PF), unscented particle filter (UPF) and the kernel particle filter (KPF) both in efficiency and estimation precision.  相似文献   

10.
Modified unscented particle filter for nonlinear Bayesian tracking   总被引:1,自引:0,他引:1  
A modified unscented particle filtering scheme for nonlinear tracking is proposed, in view of the potential drawbacks (such as, particle impoverishment and numerical sensitivity in calculating the prior) of the conventional unscented particle filter (UPF) confronted in practice. Specifically, a different derivation of the importance weight is presented in detail. The proposed method can avoid the calculation of the prior and reduce the effects of the impoverishment problem caused by sampling from the proposal distribution, Simulations have been performed using two illustrative examples and results have been provided to demonstrate the validity of the modified UPF as well as its improved performance over the conventional one.  相似文献   

11.
基于集合卡尔曼滤波的改进粒子滤波算法   总被引:3,自引:0,他引:3  
提出一种基于集合卡尔曼滤波的粒子滤波改进方法。该方法利用集合卡尔曼滤波的最大后验概率估计产生粒子滤波每一时刻各粒子的建议分布函数,使建议分布函数融入最新观测信息的同时,更加符合状态的真实后验概率分布。该方法在对粒子滤波的建议分布进行估计时使用采样方法近似非线性分布,且采样点数灵活可变,使计算精度和算法效率得到提高。仿真结果表明,提出的集合卡尔曼粒子滤波的估计性能明显优于标准粒子滤波、扩展卡尔曼粒子滤波和无迹粒子滤波。  相似文献   

12.
基于IEK-PF的多传感器序贯融合跟踪   总被引:1,自引:0,他引:1  
针对粒子滤波中得到优化的重要性密度函数比较困难的问题,将迭代扩展卡尔曼滤波和序贯融合与粒子滤波相结合,应于雷达和红外多传感器目标融合跟踪.利用基于迭代扩展卡尔曼滤波的序贯融合算法得到的系统状态更新矩阵和误差协方差矩阵来构造粒子滤波的重要性密度函数,使重要性密度函数能够融入最新观测信息的同时,更加符合真实状态的后验概率分布.仿真结果表明基于序贯融合的迭代扩展卡尔曼粒子滤波(IEK-PF)能提高状态估计的精度.  相似文献   

13.
Bayesian target tracking based on particle filter   总被引:7,自引:0,他引:7  
1 .INTRODUCTIONIn many fields including target tracking, robotics ,signal processing, ti me-series analysis , etc , theKal manfilter is one of the most widely used methodsfor esti mationinlinear Gaussiansystemand measure-ment models . However , the application of theKal man filter to nonlinear systems can be difficult .Most common approach is to use the extendedKal manfilter (EKF) .EKFsi mplylinearizes all non-linear models by using Taylor series expansions andcan, however , lead to p…  相似文献   

14.
Many Bayesian learning approaches to the multi-layer perceptron (MLP) parameter optimization have been proposed such as the extended Kalman filter (EKF). This paper uses the unscented Kalman particle filter (UPF) to train the MLP in a selforganizing state space (SOSS) model. This involves forming augmented state vectors consisting of all parameters (the weights of the MLP) and outputs. The UPF is used to sequentially update the true system states and high dimensional parameters that are inherent to the SOSS model for the MLP simultaneously. Simulation results show that the new method performs better than traditional optimization methods.  相似文献   

15.
针对连续弱测量中存在高斯测量噪声的问题,提出一种基于卡尔曼滤波的在线量子状态估计的预测-修正-投影优化算法.首先,在常规在线卡尔曼滤波算法预测状态时间更新和估计状态测量更新的基础上,通过增加对量子态的约束条件,将其应用于在线的量子状态估计中,将量子态在线估计问题转化为一个带有量子态约束条件的卡尔曼滤波优化问题.其次,通...  相似文献   

16.
针对现有机动目标跟踪中粒子滤波算法的不足,提出了一种改进的粒子滤波方法。该方法在高斯粒子滤波的基础上通过利用当前时刻量测值对量测误差的分布参数进行实时的统计和更新,并以此得到粒子的权值,从而考虑到了量测值对估计值的影响,该方法适合于量测误差分布为高斯白噪声且状态量与量测误差相关条件下的非线性估计。仿真结果表明,与传统的自举粒子滤波(boot trap particle filter, BPF)、高斯粒子滤波(Gaussian particle filter, GPF)以及无迹粒子滤波(unscented particle filter, UPF)相比,该方法具有较高的精度和较少的计算量。  相似文献   

17.
A marginalized particle filtering(MPF)approach is proposed for target tracking under the background of passive measurement.Essentially,the MPF is a combination of particle filtering technique and Kalman filter.By making full use of marginalization,the distributions of the tractable linear part of the total state variables are updated analytically using Kalman filter,and only the lower-dimensional nonlinear state variable needs to be dealt with using particle filter.Simulation studies are performed on an illustrative example,and the results show that the MPF method leads to a significant reduction of the tracking errors when compared with the direct particle implementation.Real data test results also validate the effectiveness of the presented method.  相似文献   

18.
闪烁噪声下的改进粒子滤波跟踪算法   总被引:2,自引:0,他引:2  
在实际雷达目标跟踪系统中,雷达量测常受到闪烁噪声干扰,传统的滤波算法在闪烁噪声下,滤波性能急剧下降甚至发散。提出了一种改进的粒子滤波(particle filter, PF)算法,按照高斯牛顿迭代方法对迭代扩展卡尔曼滤波(iterated extended Kalman filter, IEKF)中的测量更新进行修正,利用修正的IEKF来产生PF的重要性密度函数。进一步,采用马尔科夫链蒙特卡罗(Markov chain Monte Carlo, MCMC)方法来消除重采样引起的粒子贫化问题。在给出的闪烁噪声统计模型基础上,将所提算法与PF及MCMCPF算法进行了仿真比较,结果表明该算法具有更好的跟踪性能。  相似文献   

19.
This paper proposes a particle swarm optimization(PSO) based particle filter(PF) tracking framework,the embedded PSO makes particles move toward the high likelihood area to find the optimal position in the state transition stage,and simultaneously incorporates the newest observations into the proposal distribution in the update stage.In the proposed approach,likelihood measure functions involving multiple features are presented to enhance the performance of model fitting.Furthermore,the multi-feature weights are self-adaptively adjusted by a PSO algorithm throughout the tracking process.There are three main contributions.Firstly,the PSO algorithm is fused into the PF framework,which can efficiently alleviate the particles degeneracy phenomenon.Secondly,an effective convergence criterion for the PSO algorithm is explored,which can avoid particles getting stuck in local minima and maintain a greater particle diversity.Finally,a multi-feature weight self-adjusting strategy is proposed,which can significantly improve the tracking robustness and accuracy.Experiments performed on several challenging public video sequences demonstrate that the proposed tracking approach achieves a considerable performance.  相似文献   

20.
欺骗路径规划是作战仿真中的研究内容之一。对于欺骗路径,传统的路径识别方法存在很大的局限性,识别效率不高。针对目前路径识别方法中存在的不足,提高对欺骗路径的识别效果,将粒子滤波技术引入到欺骗路径识别领域。通过建立系统状态方程和观测方程,一方面降低观测噪声带来的干扰,准确把握当前时刻识别对象的位置信息;另一方面根据采集到的动态数据估计欺骗模型中的关键参数,从而对识别对象的运动趋势和真实目标进行判断。仿真实验表明,基于粒子滤波技术的欺骗路径识别方法能够提升识别效率,准确地判断出识别对象的真实进攻目标。  相似文献   

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