METHOD FOR FINDING LATITUDE AND LONGITUDE AND TIMEPIECE UTILIZING METHOD THEREOF

摘要

PURPOSE: To determine the approximate latitude and longitude of the place at the time without depending on an artificial satellite by determining the present longitude by comparing the time at the site and the time in a reference time region, measuring the inclination of the geomagnetic field to the horizontal face, and determining the latitude at the site based on the inclination. CONSTITUTION: Since the time regions are determined by dividing the surface of the globe into 24 regions at angular width of 15 degrees, respectively, the content of the time difference counter 25 corresponds approximately to the display of the longitude of the place where a person who put on the watch. Consequently, these contents compose time difference data necessary for an electronic control means 22. Unidirectional magnetic sensors 32, 34 measure two horizontal components Bx , By of the geomagnetic field and a unidirectional magnetic sensor 36 measures the vertical component Bz . Three measurement intensities are sent to the means 22 and the means 22 can compute the inclination of the magnetic field to the horizontal face based on these three components-measured values of the geomagnetic field. Moreover, the means 22 can determine the value of the latitude of the place where the user locates as a function of the time region and the inclination of the geomagnetic field determined by the sensors 32, 34, 36.