In view of on the incomplete consideration of noise correlation in the fixed-interval smoothing algorithm for maneuvering target tracking
an optimal fixed-interval smoothing algorithm is proposed for discrete-time linear system with general correlated measurement noises and process noises. Based on the linear unbiased minimum variance estimation theory
the new algorithm estimates the system states recursively by using the centralized expanding-dimension method with all measurements in the fixed interval
and calculates the correlations between the errors precisely using analysis of the error transfer property. Compared with the uncorrelated Kalman smoothing algorithm and the forward-backward filtering based fusion-smoothing algorithm in which only the measurement noises correlation is considered
the new algorithm is the best one under the hypothesis of Gauss distribution. Bigger the correlation coefficient is
more obvious the superiority of the new algorithm is. Simulation results show that when the correlation coefficient is 0.36
the root mean square error of position tracking of the new algorithm is decreased 38% or more compared with the uncorrelated and measurement correlated Kalman smoothing algorithm.
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references
MIRKIN L,TADMDR G. Fixed-lag smoothing as a constrained version of the fixed-interval case [C]∥Proceedings of the 2004 American Control Conference. Boston, Massachusetts, USA: American Automatic Control Council, 2004: 4165-4170.
DONALD C F, JAMES E P. The optimum linear smoother as a combination of two optimum linear filters [J]. IEEE Transactions on Automatic Control, 1969, 14(8): 387-390.
SUN Shuli, MA Jing. Optimal filtering and smoothing for discrete-time stochastic singular systems [J]. Signal Processing, 2007, 87(1): 189-201.
NAKAMORI S, HERMOSO-CARAZO A, LINARES-PEREZ J. A general smoothing equation for signal estimation using randomly delayed observations in the correlated signal-noise case [J]. Digital Signal Processing, 2006(16): 369-388.
HERMOSO-CARAZO A, LINARES-PEREZ J. Linear smoothing for discrete-time systems in the presence of correlated disturbances and uncertain observations [J]. IEEE Transactions on Automatic Control, 1995, 40(8): 1486-1488.
DENG Zili, SHI Yin, SUN Shuli, et al. Fast suboptimal fixed-interval Wiener smoothing algorithm [J]. Control Theory Applications, 2004, 21(2): 275-278.
HAN Chongzhao, WANG Jie, LI Xiaorong. Smoothing algorithm for linear systems with general correlated measurement noises [J]. Journal of Xi'an Jiaotong University, 2000, 34(9): 1-4.
ZUO Dongguang, HAN Chongzhao, WEI Ruixuan,et al. Tracks association and fusion in case of correlated noises [J]. Acta Electronica Sinica, 2002, 30(8): 1117-1120.
LI Xiaorong, ZHU Yunmin, WANG Jie, et al. Optimal linear estimation fusion, part I: unified fusion rules [J]. IEEE Transactions on Information Theory, 2003, 49(9): 2192-2208.