RADIO DEVICE AND RADIO TAG COMMUNICATION DEVICE

摘要

There is provided a radio device capable of detecting a direction of a communication object with high resolution by simple processing. The radio device includes: PAA processing unit (44) for controlling the reception directivity by a reception antenna (30); a reception signal intensity detection unit (52) for detecting a reception signal intensity received by the reception antenna (30); and a direction detection unit (54) for detecting the direction of a radio tag (14) according to the direction where the greater reception signal intensity becomes minimum, i.e., the reception signal intensity when the reception directivity is determined to be a first directivity direction by a PAA processing unit (44) or the reception signal intensity when the reception directivity is determined to be a second directivity direction different from the first directivity direction by a predetermined angle. By utilizing the characteristic that the reception signal intensity becomes minimum at the valley of the gain having superimposed main lobes in two directivity directions which are different from each other by a predetermined angle, it is possible to obtain a resolution higher than when the main lobe itself with the maximum communication sensitivity with the radio tag (14) is used. It is also possible to preferably detect its direction.