Relay apparatus, wireless communication system, wireless communication method and program

A wireless communication system comprising:

• a plurality of first communication devices;
• a second communication device;
• and
• a relay device configured to relay signals transmitted from the plurality of first communication devices to the second communication device while moving,
• wherein each of the plurality of first communication devices includes a first transmitter that transmits the first uplink signal to the relay device, and
• wherein the relay device includes
• a first receiver that receives first uplink signals transmitted from the plurality of first communication devices through a reception antenna,
• second transmitter configured to transmit a downlink signal indicating reception information regarding reception of the first uplink signals to the second communication device;
• a second receiver that receives a second uplink signal which is transmitted from the second communication device and is based on dense district information indicating a district estimated based on the reception information;
• and
• a direction controller that controls a reception direction of the reception antenna based on the dense district information and indicates the district where the first communication devices are located with high density exceeding a predetermined reference,
• wherein the district is estimated based on positional information, which is included in the first uplink signals and indicates positions of the first communication devices that have transmitted the first uplink signals.

A wireless communication method in which signals transmitted from a plurality of first communication devices to a second communication device are relayed by a relay device that is moving, the method comprising:

• a first transmission step in which each of the plurality of first communication devices transmits a first uplink signal to the relay device;
• a first reception step in which the relay device receives first uplink signals transmitted from the plurality of first communication devices through a reception antenna;
• a second transmission step in which the relay device transmits a downlink signal indicating reception information regarding reception of the first uplink signals to the second communication device;
• a second reception step in which the relay device receives a second uplink signal which is transmitted from the second communication device and is based on dense district information indicating a district estimated based on the reception information;
• and
• a direction control step in which the relay device controls a reception direction of the reception antenna based on the dense district information and indicates the district where the first communication devices are located with high density exceeding a predetermined reference,
• where the district is estimated based on positional information, which is included in the first uplink signals and indicates positions of the first communication devices that have transmitted the first uplink signals.

A non-transitory storage medium that stores a program causing a computer to execute processes as a relay device, the processes comprising:

• receiving first uplink signals transmitted from the plurality of first communication devices through a reception antenna;
• transmitting a downlink signal indicating reception information regarding reception of the first uplink signals to the second communication device;
• receiving a second uplink signal which is transmitted from the second communication device and is based on dense district information indicating a district estimated based on the reception information;
• and
• controlling a reception direction of the reception antenna based on the dense district information and indicates the district where the first communication devices are located with high density exceeding predetermined reference,
• wherein the district is estimated based on positional information, which is included in the first uplink signals and indicates positions of the first communication devices that have transmitted the first uplink signals.