Patent ID: 8115594

Claim:
A tag communication device for performing wireless communications with a radio frequency identification (RFID) tag attached to a moving body via a radio wave, the tag communication device comprising: an antenna that receives a plurality of information signals read from the RFID tag, each of the information signals including at least a tag identification, wherein the antenna is a scan antenna, having a plurality of antenna elements and wherein the scan antenna scans an area including a path of the RFID tag; and a moving detection section for determining a moving direction of the RFID tag based on the plurality of information signals received by the antenna and time information corresponding to each of the wireless communications, wherein the moving detection section is configured to calculate a linear approximate straight line to show the relation between a scan angle and the time information, and the moving detection section is configured to determine the moving direction of the RFID tag based on an inclination of the linear approximate straight line.