Communication control apparatus, communication system, and method

A communication system comprising:

• a plurality of wireless communication apparatuses that communicate with a terminal;
• and
• a communication control apparatus that controls the plurality of wireless communication apparatuses, wherein
• each of the plurality of wireless communication apparatuses includes:
• at least one wireless memory storing instructions, and
• at least one wireless processor configured to execute the instructions to;
• receive a reference signal, which has been subjected to orthogonal time frequency space modulation, transmitted from the terminal via an antenna;
• and
• transmit a data signal with directivity of the antenna under control from the communication control apparatus,
• the communication control apparatus includes:
• at least one control memory storing instructions, and
• at least one control processor configured to execute the instructions to;
• estimate, for each of the plurality of wireless communication apparatuses, a signal delay amount from the terminal to the antenna and a relative velocity between the terminal and the wireless communication apparatus based on the reference signal received from the terminal by each of the plurality of wireless communication apparatuses;
• estimate a position and a velocity vector of the terminal based on positions of the plurality of wireless communication apparatuses, and the signal delay amount and the relative velocity estimated for each of the plurality of wireless communication apparatuses;
• and
• select a predetermined wireless communication apparatus closest to the terminal from among the plurality of wireless communication apparatuses based on the position of the terminal and the positions of the plurality of wireless communication apparatuses, identifying an estimated position of the terminal when a data signal is to be transmitted from the predetermined wireless communication apparatus based on the position and the velocity vector of the terminal when the reference signal is received by the predetermined wireless communication apparatus, and control the predetermined wireless communication apparatus to transmit the data signal with the directivity of the antenna being oriented in a direction from the predetermined wireless communication apparatus toward the estimated position of the terminal,
• a first frequency is used for a signal from the terminal to the wireless communication apparatus, and
• a second frequency, which is higher in frequency than the first frequency, is used for a signal from the wireless communication apparatus to the terminal.

A method comprising:

• estimating, for each of a plurality of wireless communication apparatuses, a signal delay amount from a terminal to an antenna of the wireless communication apparatus and a relative velocity between the terminal and the wireless communication apparatus based on a reference signal, which has been subjected to orthogonal time frequency space modulation, received from the terminal by each of the plurality of wireless communication apparatuses;
• estimating a position and a velocity vector of the terminal based on positions of the plurality of wireless communication apparatuses, and the signal delay amount and the relative velocity estimated for each of the plurality of wireless communication apparatuses;
• selecting a predetermined wireless communication apparatus closest to the terminal from among the plurality of wireless communication apparatuses based on the position of the terminal and the positions of the plurality of wireless communication apparatuses;
• identifying an estimated position of the terminal when a data signal is to be transmitted from the predetermined wireless communication apparatus based on the position and the velocity vector of the terminal when the reference signal is received by the predetermined wireless communication apparatus;
• and
• controlling the predetermined wireless communication apparatus to transmit the data signal with directivity of the antenna being oriented in a direction from the predetermined wireless communication apparatus toward the estimated position of the terminal, wherein
• a first frequency is used for a signal from the terminal to the wireless communication apparatus, and
• a second frequency, which is higher in frequency than the first frequency, is used for a signal from the wireless communication apparatus to the terminal.