2006-153695 is referenced by 10 patents.

PROBLEM TO BE SOLVED: To reduce the power consumption of a position detection device born by a user or mounted in a vehicle, and used for checking the whereabouts of an old person or a child, or for searching a stolen vehicle by transmitting the result of the positioning with GPS to a management center etc. through cellular phone network.SOLUTION: The positioning device 1 elongates the positioning interval by determining that the device is in a stationary state if no change in the waiting base station has been happening, in achieving the saving of the consumption power of GPS positioning means which consumes significant electric power. Also if the GPS reception is incapable, the positioning is stopped. On the other hand, if something has happened in the base station, the regular positioning is performed under the determination that the device is in moving state. Consequently, the power consumption is further saved by using the results of communication to the base station which is remarkably small in power consumption instead of using the results of GPS positioning itself in the determination of the moving of the position detecting device.

Title
Method and device for position detection
Application Number
2004-345747
Publication Number
2006-153695
Application Date
November 30, 2004
Publication Date
June 15, 2006
Inventor
Kawamoto Kazuhiro
Koyama Masaki
Okuno Kenji
Tsujimoto Ikuo
Fukuda Masahito
Suzuki Junichi
Honda Kazuhiro
Sakamoto Koji
Assignee
Matsushita Electric Works
IPC
H04Q 07/34
H04B 07/26
G08G 01/13
G08B 25/10
G01S 05/14