the distribution model. Since the characteristics of horizontal and vertical positioning
errors are identical, this paper only calculates the self-correlation function of vertical
positioning error of single-point positioning and differential positioning, as shown in
Figs. 6 and 7.
It can be seen qualitatively from Figs. 6 and 7 that the self-correlation of the singlepoint positioning error sequence is high and the samples are not independent which
makes it difficult to meet the requirements of modeling. However, the self-correlation
of the differential positioning error sequence is low and the samples are nearly independent. So the distribution model can be directly established for integrity evaluation.
Fig. 6. Self-correlation function of single-point positioning error sequence
Fig. 7. Self-correlation function of differential positioning error sequence
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H. Li et al.
errors are identical, this paper only calculates the self-correlation function of vertical
positioning error of single-point positioning and differential positioning, as shown in
Figs. 6 and 7.
It can be seen qualitatively from Figs. 6 and 7 that the self-correlation of the singlepoint positioning error sequence is high and the samples are not independent which
makes it difficult to meet the requirements of modeling. However, the self-correlation
of the differential positioning error sequence is low and the samples are nearly independent. So the distribution model can be directly established for integrity evaluation.
Fig. 6. Self-correlation function of single-point positioning error sequence
Fig. 7. Self-correlation function of differential positioning error sequence
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H. Li et al.