Wireless communication system, wireless communication method, and base station device
In a wireless communication system, a base station device communicates with a terminal device via any relay device (reconfigurable intelligent surface). The base station device stores a CSI when passing through the relay device in association with the object arrangement information. When the current object arrangement information is similar to the stored past object arrangement information, the base station device determines a relay device to be used at the present time on the basis of each CSI stored in association with the past object arrangement information. According to this, it is possible to reduce overhead for acquiring the CSI, and simultaneously execute the use determination of the plurality of reconfigurable intelligent surfaces, by re-using the CSI.
1 . A wireless communication system including a base station device, a terminal device, and at least a first relay device and a second relay device, wherein the first relay device and the second relay device each have a reconfigurable intelligent surface that reflects a radio wave, and the base station device is able to use a first channel for communicating with the terminal device via the reconfigurable intelligent surface of the first relay device, and a second channel through which the base station device communicates with the terminal device via the reconfigurable intelligent surface of the second relay device,
wherein the base station device includes:
a sensor which acquires object position information including positions of an obstacle and the terminal device;
radio circuitry which acquires first channel state information of the first channel and second channel state information of the second channel;
an information storage memory which stores past object position information acquired by the sensor, and the first channel state information and the second channel state information acquired by the radio circuitry with respect to the past object position information in association with each other;
similarity determination circuitry which determines whether current object position information acquired by the sensor is similar to the past object position information stored in the information storage memory; and
relay device determination circuitry which determines a relay device to be used at a present time, among the first relay device and the second relay device, on the basis of the first channel state information and the second channel state information associated with the past object position information similar to the current object position information, when it is determined that the current object position information is similar to the past object position information.
2 . The wireless communication system according to claim 1 , wherein the sensor includes:
an image sensor which photographs a plurality of regions divided into a grid shape, and
environment information acquisition circuitry which searches for image data of the plurality of regions photographed by the image sensor, and acquires a position of a region in which the obstacle exists and a position of a region in which the terminal device exists as the object position information, and
wherein the similarity determination circuitry determines that the current object position information is similar to the past object position information, when the region in which the obstacle exists and the region in which the terminal device exists in the current object position information are the same as the region in which the obstacle exists and the region in which the terminal device exists in the past object position information.
3 . The wireless communication system according to claim 2 , wherein:
each of the plurality of regions corresponds to one of a plurality of tiles disposed on a floor surface.
4 . A wireless communication method for use with a first channel through which a base station device communicates with a terminal device via a reconfigurable intelligent surface of a first relay device and a second channel through which the base station device communicates with the terminal device via a reconfigurable intelligent surface of a second relay device, the method comprising:
acquiring object position information including positions of an obstacle and the terminal device;
acquiring first channel state information of the first channel and second channel state information of the second channel;
storing past object position information, and the first channel state information and the second channel state information acquired step with respect to the past object position information in association with each other;
determining whether current object position information is similar to the past object position information; and
determining a relay device to be used at a present time, among the first relay device and the second relay device, on the basis of the first channel state information and the second channel state information associated with the past object position information similar to the current object position information, when it is determined that the current object position information is similar to the past object position information.
5 . The wireless communication method according to claim 4 , wherein:
the base station device includes an image sensor which photographs a plurality of regions divided into a grid shape,
the acquiring object position information includes searching for image data of the plurality of regions photographed by the image sensor, and acquiring a position of a region in which the obstacle exists and a position of a region in which the terminal device exists as the object position information, and
the determining whether the current object position information is similar to the past object position includes determining that the current object position information is similar to the past object position information, when the region in which the obstacle exists and the region in which the terminal device exists in the current object position information are the same as the region in which the obstacle exists and the region in which the terminal device exists in the past object position information.
6 . The wireless communication method according to claim 5 , wherein:
each of the plurality of regions corresponds to each of a plurality of tiles disposed on a floor surface.
7 . A base station device for use with a first channel through which the base station device communicates with a terminal device via a reconfigurable intelligent surface of a first relay device and a second channel through which the base station device communicates with the terminal device via a reconfigurable intelligent surface of a second relay device, the base station device comprising:
a sensor which acquires object position information including positions of an obstacle and the terminal device;
radio circuitry which acquires first channel state information of the first channel and second channel state information of the second channel;
an information storage memory which stores past object position information acquired by the sensor, and the first channel state information and the second channel state information acquired by the radio circuitry with respect to the past object position information in association with each other;
similarity determination circuitry which determines whether current object position information acquired by the sensor is similar to the past object position information stored in the information storage memory; and
relay device determination circuitry which determines a relay device to be used at a present time, among the first relay device and the second relay device, on the basis of the first channel state information and the second channel state information associated with the past object position information similar to the current object position information, when it is determined that the current object position information is similar to the past object position information.
8 . The base station device according to claim 7 , wherein the sensor includes:
an image sensor which photographs a plurality of regions divided into a grid shape, and
environment information acquisition circuitry which searches for image data of the plurality of regions photographed by the image sensor, and acquires a position of a region in which the obstacle exists and a position of a region in which the terminal device exists as the object position information,
wherein the similarity determination circuitry determines that the current object position information is similar to the past object position information, when the region in which the obstacle exists and the region in which the terminal device exists in the current object position information are the same as the region in which the obstacle exists and the region in which the terminal device exists in the past object position information.