Patent ID: 8111680
Filing Date: 2012-02-07
Classification: G01S

Abstract:
1. A mobile object information sharing system comprising a plurality of mobile stations, wherein each mobile station includes: a radio device for communicating mutually at one radio frequency; a GPS receiver that obtains, by GPS radio waves, at least position information and moving speed information of its own station and shared time information; a time division synchronous radio modem device that synchronizes mutually among the plurality of mobile stations using the shared time information, after this time synchronization, sets a fundamental transmission period by arranging continuously a plurality of transmission slots having a predetermined time width, verifies the use status of the plurality of transmission slots during the fundamental transmission period, transmits the position information of its own station to the radio device in an optional period of the plurality of transmission slots, and receives the position information of other mobile stations; a transmission period determining unit for determining the optional period using the moving speed of the mobile station; and an operation unit that determines a transmission timing among the plurality of transmission slots based on the optional period determined by the transmission period determining unit and transmits the position information of its own station, and the mobile station further includes a movement monitoring unit that monitors the movement trajectory of its own station and, when the moving direction has changed equal to or greater than a predetermined angle within a predetermined time, stores the position and the time, and when the position and the time is stored in the movement monitoring unit, the mobile station transmits the information of the position and the time at a timing of the position information of its own station immediately after the time.