DEVICE AND METHOD FOR DETERMINING A ROUGH COMPONENT OF A LATITUDE OR LONGITUDE POSITION OF A MOVING CRAFT

摘要

A device and a method for determining a rough component of a latitude or longitude position of a moving craft. The position is reconstructed cyclically by combining the rough component with a corresponding fine component. The device determines the sign of a difference between the fine component for an acquisition cycle and the fine component for a preceding acquisition cycle. The device then computes the rough component corresponding to the given acquisition cycle of the fine component, as a function of the sign of the difference and of the sign and of the value of the speed of the craft. The device and the corresponding method make it possible to extrapolate an unrefreshed rough component as a function of the trend of the fine component and of the sign of the speed of the moving craft to reduce error associated with the computation of the latitude or longitude position.

主权项

1. A device for determining a coarse component of a latitude or longitude position datum of a moving craft, said position datum being reconstructed cyclically in accordance with cycles of reconstruction of the position datum, by combining said coarse component acquired cyclically in accordance with cycles of acquisition of the coarse component, with a corresponding fine component acquired cyclically in accordance with cycles of acquisition of the fine component, comprising:
a first determination module configured to determine a sign of a difference between the fine component for a given cycle of acquisition of the fine component and the fine component for the preceding cycle of acquisition of the fine component; a second determination module configured to determine a sign and a value of the speed of the craft; a computer configured to compute the coarse component corresponding to said given cycle of acquisition of the fine component, as a function of said sign of the difference between the fine component for said given cycle of the fine component and the fine component for said preceding cycle of the fine component, and as a function of said sign and said value of the speed of the craft.