Object detection method, object detection device, and object detection system
A wireless transmission device transmits a radio signal with a plurality of beam patterns and outputs transmission beam identifiers corresponding to the beam patterns to an object detection device, a wireless reception device receives the radio signal transmitted by the wireless transmission device with a plurality of beam patterns, measures received signal strength for each of the beam patterns and outputs reception beam identifiers and the received signal strength to the object detection device, and the object detection device detects an object within a detection area on the basis of the transmission beam identifiers, the reception beam identifiers and the received signal strength. This enables device-free object detection by utilizing a beamforming function, so that it is possible to achieve high detection accuracy while preventing increase in cost.
1. An object detection method for detecting an object within a detection area by an object detection device on a basis of information output by a wireless transmission device and a wireless reception device each having a beamforming function, wherein
the wireless transmission device transmits a radio signal with a plurality of beam patterns determined in advance and outputs transmission beam identifiers corresponding to the beam patterns to the object detection device,
the wireless reception device receives the radio signal transmitted by the wireless transmission device with a plurality of beam patterns determined in advance, measures received signal strength for each of the beam patterns and outputs reception beam identifiers and the received signal strength corresponding to the beam patterns to the object detection device, and
the object detection device is connected to the wireless transmission device and the wireless reception device and detects the object within the detection area on a basis of the transmission beam identifiers input from the wireless transmission device, and the reception beam identifiers and the received signal strength corresponding to the reception beam identifiers input from the wireless reception device.
2. The object detection method according to claim 1 ,
wherein the object detection device
creates a database of received signal strength corresponding to each combination of the transmission beam identifiers and the reception beam identifiers,
holds the database for premeasurement in a case where there is no object within the detection area as a premeasurement database,
holds the database for main measurement in which the object within the detection area is detected as a main measurement database, and
compares the received signal strength in the premeasurement database with the received signal strength in the main measurement database for each combination of the transmission beam identifiers and the reception beam identifiers to detect the object within the detection area.
3. The object detection method according to claim 1 ,
wherein the object detection device
creates a database of received signal strength corresponding to each combination of the transmission beam identifiers and the reception beam identifiers,
holds the database for premeasurement in a case where there is no object within the detection area as a first premeasurement database,
holds, as a second premeasurement database, the database for premeasurement in a case where an object for learning is disposed in each mesh-like area obtained by dividing the detection area into mesh-like areas and sets the mesh-like area for which an absolute value of a difference between the received signal strength in the first premeasurement database and the received signal strength in the second premeasurement database is equal to or greater than a threshold determined in advance, as an effective area,
holds the database for main measurement in which the object within the detection area is detected as a main measurement database, and
compares the received signal strength in the first premeasurement database with the received signal strength in the main measurement database, which are set for the effective area, for each combination of the transmission beam identifiers and the reception beam identifiers to detect the object within the detection area.
4. An object detection device that detects an object within a detection area on a basis of information output by a wireless transmission device and a wireless reception device each having a beamforming function,
the object detection device comprising an analysis unit configured to
receive, from the wireless transmission device that transmits a radio signal with a plurality of beam patterns determined in advance, input of transmission beam identifiers corresponding to the beam patterns,
receive, from the wireless reception device that receives the radio signal transmitted by the wireless transmission device with a plurality of beam patterns determined in advance and measures received signal strength for each of the beam patterns, input of reception beam identifiers and the received signal strength corresponding to the beam patterns, and
detect the object within the detection area on a basis of the transmission beam identifiers input from the wireless transmission device, and the reception beam identifiers and the received signal strength corresponding to the reception beam identifiers input from the wireless reception device.
5. The object detection device according to claim 4 ,
wherein the analysis unit
creates a database of received signal strength corresponding to each combination of the transmission beam identifiers and the reception beam identifiers,
holds the database for premeasurement in a case where there is no object within the detection area as a premeasurement database,
holds the database for main measurement in which the object within the detection area is detected as a main measurement database, and
compares the received signal strength in the premeasurement database with the received signal strength in the main measurement database for each combination of the transmission beam identifiers and the reception beam identifiers to detect the object within the detection area.
6. The object detection device according to claim 4 ,
wherein the analysis unit
creates a database of received signal strength corresponding to each combination of the transmission beam identifiers and the reception beam identifiers,
holds the database for premeasurement in a case where there is no object within the detection area as a first premeasurement database,
holds, as a second premeasurement database, the database for premeasurement in a case where an object for learning is disposed in each mesh-like areas obtained by dividing the detection area into mesh-like areas and sets the mesh-like area for which an absolute value of a difference between the received signal strength in the first premeasurement database and the received signal strength in the second premeasurement database is equal to or greater than a threshold determined in advance, as an effective area,
holds the database for main measurement in which the object within the detection area is detected as a main measurement database, and
compares the received signal strength in the first premeasurement database with the received signal strength in the main measurement database, which are corresponding to the effective area, for each combination of the transmission beam identifiers and the reception beam identifiers to detect the object within the detection area.
7. An object detection system including an object detection device that detects an object within a detection area on a basis of information output by a wireless transmission device and a wireless reception device each having a beamforming function, wherein
the wireless transmission device transmits a radio signal with a plurality of beam patterns determined in advance and outputs transmission beam identifiers corresponding to the beam patterns to the object detection device,
the wireless reception device receives the radio signal transmitted by the wireless transmission device with a plurality of beam patterns determined in advance, measures received signal strength for each of the beam patterns and outputs reception beam identifiers and the received signal strength corresponding to the beam patterns to the object detection device, and
the object detection device is connected to the wireless transmission device and the wireless reception device and detects the object within the detection area on a basis of the transmission beam identifiers input from the wireless transmission device, and the reception beam identifiers and the received signal strength corresponding to the reception beam identifiers input from the wireless reception device.
8. The object detection system according to claim 7 ,
wherein the object detection device
creates a database of received signal strength corresponding to each combination of the transmission beam identifiers and the reception beam identifiers,
holds the database for premeasurement in a case where there is no object within the detection area as a premeasurement database,
holds the database for main measurement in which the object within the detection area is detected as a main measurement database, and
compares the received signal strength in the premeasurement database with the received signal strength in the main measurement database for each combination of the transmission beam identifiers and the reception beam identifiers to detect the object within the detection area.