Concerning the advantage of particle filter in non-linear systems
and the problem of noise influence during the dissemination process
an improved particle filter algorithm with threshold de-noising is proposed. The idea of wavelet threshold de-noising is introduced into the particle filter
that is
after applying the wavelet packet decomposition on the signal
the coefficients that are greater than a certain threshold are reserved while other coefficients are set to 0. Thus
with the assistance of particle history information
the noise is reduced and the estimated filter state value is more accurate. Monte Carlo simulation results show that the particle filter with threshold de-noising can effectively reduce the filter root mean square error(RMSE)and improve filter accuracy
and that RMSEs in the corresponding linear and non-linear systems are reduced by 14% and 12% respectively.
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references
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