| 摘要 |
A method and associated algorithm for filtering time-varying location solution coordinates Px,n, Py,n and Pz,n (301) determined by a Satellite Positioning System (SATPS), which operates in a static mode and a dynamic mode (303), to reduce large discontinuities and control the rate at which a changing sequence of measurement errors can induce a change in a sequence of position solutions. The method forms sequences of filtered location coordinates {P &cir& x,n}, {P &cir& y,n} and {P &cir& z,n} (325), smoothed to reduce discontinuities that occur with a changing set of measurement errors. The filtered location coordinates P &cir& x,n, P &cir& y,n and P &cir& z,n (325) are formed as linear combinations of the respective unfiltered location solutions Px,n, Py,n and Pz,n (301) with predicted location coordinates P &cir& x,n-, P &cir& y,n- and P &cir& z,n-. The predicted location coordinates for the present fix time t=tn are formed by projecting ahead the respective preceding filtered location coordinates P &cir& x,n-1, P &cir& y,n-1 and P &cir& z,n-1 for the preceding fix time t=tn-1, using the respective average velocities sqrt(Vx,n + Vx,n-1), sqrt(Vy,n + Vy,n-1) and sqrt(Vz,n + Vz,n-1) in the time interval tn-1 </= t >/= tn.
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