Securing a third person position information search to prevent a loss of privacy by degrading position information sent through a communication system

摘要

A mobile terminal 100 includes a position information detection part 8 that detects current position information, a position information decoder part 9 that calculates the current position information as latitude/longitude information, and a position accuracy degradation-producing part 10 that degrades the apparent accuracy of the latitude/longitude information in plural levels. In operation, when a position search request is made from a third-party terminal, the mobile terminal 100 transmits position information with an accuracy according to the authentication result (such as the result of password verification) of the third-person terminal concerned. Therefore, when e.g. the password has been stolen, position information with an accuracy intentionally degraded by the user of the mobile terminal can be transmitted, thereby preventing a loss of privacy or stalking. In the event of an emergency call, good accuracy can always be used.