Object detection system, object detection method, and non-transitory computer-readable storage medium in which object detection program is stored

This object detection system is provided with: a reader waveguide (101) constituted by an open transmission line; an RFID tag (102) situated above the reader waveguide (101); a signal strength acquisition unit (103) for acquiring the signal strength of a read signal read from the RFID tag (102) by electromagnetic coupling through the reader waveguide (101); and an object detection unit (104) for detecting a physical characteristic of an object (105) corresponding to the acquired signal strength, on the basis of the relationship between a physical characteristic of an object targeted for detection, and a plurality of signal strengths of three or more values of the read signal. It is possible for the accuracy of detection of objects to be improved thereby.