Patent ID: 8649781
Filing Date: 2014-02-11
Classification: G01S,G08B,H04W

Abstract:
1. A mobile object monitoring system comprising: a monitoring target portable terminal; a plurality of monitor portable terminals classified into a plurality of groups; and a relay device which communicates with said monitoring target portable terminal and said monitor portable terminals, wherein said monitoring target portable terminal comprises a first control unit which performs control to transmit position information of said monitoring target portable terminal to said relay device, and said relay device comprises hardware, a position information storage unit implemented by the hardware and which stores position information transmitted from said monitoring target portable terminal, and a second control unit implemented by the hardware and which performs control to transmit a group connection request which requests group communication to all monitor portable terminals belonging to a predetermined group when position information is transmitted from said monitoring target portable terminal, wherein a priority level is set for each of said plurality of groups to which said plurality of monitor portable terminals belong as classified, each of said plurality of groups, other than a group having a highest priority level, includes a group having a priority level higher than a priority level thereof, and said second control unit performs a controlling function to transmit a group connection request to said plurality of monitor portable terminals in the descending order of the priority level first from those monitor portable terminals that belong to one of said plurality of groups that has a highest priority level thereamong, wherein said second control unit performs control to transmit position information stored in said position information storage unit to all monitor portable terminals belonging to a group with a lowest priority level, when no response is received from any monitor portable terminals belonging to the group with the lowest priority level.