Patent ID: 8005423

Claim:
A communication system, comprising: a plurality of mobile communication terminals; a server device; and a plurality of relay devices, each of the plurality of relay devices performing a relay between at least one of the plurality of mobile communication terminals and the server device, wherein each of the plurality of mobile communication terminals includes: a communication unit transmitting and receiving a first long wave wireless signal including information, and a processing unit performing a predetermined process based on the information received from the relay devices; wherein each of the plurality of relay devices includes: a first communication unit transmitting and receiving a second long wave wireless signal with respect to at least one of the plurality of mobile communication terminals, a second communication unit communicating with the server device, and a relay processing unit performing a relaying process in which information received from the server device via the second communication unit is transmitted to the at least one of the plurality of mobile communication terminals via the first communication unit, and a relaying process in which information received from the at least one of the plurality of mobile communication terminals via the first communication unit is relayed to the server device via the second communication unit; wherein the server device includes: a communication unit communicating with at least one of the plurality of relay devices, a group information storing unit storing group information on a group to which each of the plurality of mobile communication terminals belongs, and a group communication processing unit performing a group communication process in which any of the plurality of mobile communication terminals that belong to a predetermined group are extracted based on the group information so as to transmit predetermined information to the any of the plurality of mobile communication terminals that are extracted; wherein the plurality of relay devices includes: a first relay device that is placed at a first side of a predetermined gate and includes a first antenna capable of receiving a communication wave from the mobile communication terminals that are present in a predetermined area of the first side of the gate, and a second relay device that is placed at a second side, the second side being opposite to the first side, of the predetermined gate and includes a second antenna capable of receiving a communication wave from the mobile communication terminals that are present in a predetermined area of the second side of the gate; and wherein a terminal position management unit of the server device determines whether the mobile communication terminals pass the predetermined gate or not based on the information from the first relay device and the second relay device and performs an updating process to information on passage of the mobile communication terminals through the predetermined gate based on a result of the determination.