Abstract
To improve the positioning accuracy of LORN-C Northwest Pacific Chain (8930 chain), the differential
correction method was proposed in this paper and tried at Tateyama Bay in 1997. The reference station which
measures the correction value of LOP (Line of Position), was set at the land fixed point being not far from
observation sea area.
The large local LOP errors l.56μs in Y station (Hokkaido) and 2.48/`S in Z station (Korea) were observed.
It is thought that these errors were caused by the change of SF (Secondary Factor) with long land propagation of
ground wave. By using the differential correction, the LOP errors were decreased to 14.7% in Y station and
26.9% in Z station. From this result, the efficiency of differential method was verificated.
