| 摘要 |
<p><P>PROBLEM TO BE SOLVED: To acquire navigation data by a certain method in a short time. <P>SOLUTION: In a positioning system 1, a mobile-type phone 2 demands against a server 3 differential ephemeris data that is a difference between ephemeris data at a predetermined basis date and ephemeris data at a current date. The server 3 receives the demand to generate a differential ephemeris data at a current date based on the ephemeris data at the predetermined basis date and the ephemeris data at the current date, both transmitted from the mobile-type phone 2 from among ephemeris data that is sequentially acquired by a GPS satelite or an external system and is cumulatively memorized, and to transmit the differential ephemeris data to the mobile-type phone 2. The mobile-type phone 2 performs a predetermined positioning operation based on the differential ephemeris data at the current date received from the server 3 and memorized basis ephemeris data to determine a current position. <P>COPYRIGHT: (C)2009,JPO&INPIT</p> |
