Patent ID: 6774843
Filing Date: 2004-08-10
Classification: G01S

Abstract:
A method for acquiring azimuth information comprising:a step of disposing a single GPS planar antenna having a hemispherical antenna pattern with its beam center horizontal to form a sky coverage area of antenna sensitivity that is a sky quarter-sphere in a direction GPS antenna faces bounded by a great semicircle passing through the zenith; a step of causing a GPS receiver connected to the GPS antenna to attempt reception of signals transmitted by GPS satellites in the sky hemisphere; a step of processing at a date processing unit signals received by the receiver to discriminate the satellites present in the coverage area; a step of using azimuths of the satellites obtained by a positioning calculation process to arrange the satellites found to be present in the sky coverage area in clockwise order as viewed from the sky coverage area start azimuth; and a step of limiting the azimuth of a direction in which one side of the great semicircle faces within an azimuth range defined clockwise whose start azimuth is the azimuth of the satellite corresponding to the last in said order and whose end azimuth is the reverse direction from the azimuth of the satellite corresponding to the first in said order.