Why can't the dual frequency long baseline kinematic positioning be solved accurately? In kinematic positioning, the coordinates changes epoch by epoch, and the number of the observation equations per unknown does not increase. Hence, the averaging effect of the least square solution can't work well in contrast to the static positioning. So, when the baselinelength is long and the error increases, the least square solution can't give the accurate solution. Supplementary information for the correct solution would be required. In case of static positioning, a constraint that the coordinates of the receivers are constant is imposed . If a similar constraint is found in kinematic positioning, it may be a strong help to obtain the accurate solution. The initial phase ambiguity of the wide-lane combination can be obtained correctly irrespective of the baseline length by using HMW (Hatch-Melbourne-Wi bbena) combination. The ionospheric delay may be estimated with rather nice accuracy by using the external source such as IONEX and the geometry free combination. So, the use of these informationmay be useful. Specifically, a nice approximation of the coordinates is obtained by solving the wide-lane combination where the above mentioned ambiguities and the ionospheric delays are used. The ionosphere free combination is solved under the constraint of these coordinates.

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In the first report (Isshiki (2005)), theory and algorithm of a new dual frequency long baseline kinematic positioning was discussed, and the effectiveness was verified by some numerical examples. The results seem reasonable and correct. In the present report, the effect of epoch interval and measuring length is investigated by numerical calculations. The relationshipbetween the positioning error and the baseline length is also discussed. Furthermore, an algorithm for the real time application is shown.

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Secular crustal deformation in the Kanto and Tokai regions, central Japan was deduced from the wavelet decomposition analysis of the GPS time-series data acquired by Geographical Survey Institute, Japan. The time-series data during the period from April 1996 to March 2002 were assumed to be composed of several trends, i.e., seasonal, transient and secular(linear) trends along with discontinuities (co-seismic or artificial jumps) and white noises. The north-south (NS), east-west (EW) and up-down (UD) components of the time-series data were also assumed to be mutually independent. After removing data-jumps, we decomposed each of the NS, EW and UD components to the desired level of 8 by using the orthogonal Daubechies wavelets. We could recognize a seasonal variation clearly in the detail component at level 8, and could estimate a secular velocity from the approximation component at the same level.
We estimated secular horizontal velocities at about 540 GPS sites in central Japan on the basis of the wavelet decomposition analysis, and then evaluated horizontal velocities at 7 km × 7 km grid points by applying the least-square collocation method. We also estimated distributions of dilatational, maximum-shear, and principal strain rates. We could find out the following characteristics concerning the secular crustal deformation in the Kanto and Tokai regions, central Japan: (1) the entire region is generally under a compressive regime, (2) there exists a remarkably compressed area with a strain rate of 0.2×10^-6/yr near the Boso peninsula, (3) higher maximum-shear strain rates of about 0.2 × 10-6/yr are shown near the Boso peninsula and off the eastern coast of the Izu peninsula, and (4) there exists a slight dilatational area near Mt. Fuji, corresponding to the collision zone at the northern end of the Izu peninsula. The observed features of the secular crustal deformation in the Kanto and Tokai regions were approximately explained on the basis of the back-slip fault model and the antiextensional fault model. The present back-slip fault model was assumed to consist of the multiple-fault systems along the subduction boundaries, i .e., the Sagami and Suruga-Nankai troughs. The anti-extensional fault model was also presumed to locate at the collision zone between the Sagami and Suruga troughs, i.e., the area near Mt. Fuji.

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