Abstract: An RFID tag communicating apparatus transmitting a transmission signal to a predetermined RFID tag and receiving a return signal returned from the RFID tag with a plurality of antennas to communicate information with the RFID tag, includes an information communication control portion that executes the process for narrowing down the RFID tags to be objects of a second communication continued from a first communication based on a result of the first communication with the RED tags; and a received signal processing portion that separates return signals from a plurality of RFID tags included in received signals based on the received signals received by the plurality of the antennas in accordance with a predefined relationship, the first communication being performed in parallel with a plurality of the RFID tags, the information communication control portion narrowing down the RFID tags to be the objects of the second communication when the received signal processing portion separates the return signals from a plu

Abstract: An RFID tag communicating apparatus transmitting a transmission signal to a predetermined RFID tag and receiving a return signal returned from the RFID tag with a plurality of antennas to communicate information with the RFID tag, includes a received signal processing portion that separates return signals from a plurality of RFID tags included in received signals based on the received signals received with the plurality of the antennas correspondingly to a first communication in accordance with a predefined relationship; and an information communication control portion that performs a second communication continued from the first communication with at least one RFID tag of a plurality of the RFID tags corresponding to the return signals separated by the received signal processing portion.

Abstract: A patch antenna (10) includes a dielectric substrate (12), a patch conductor (14) and a ground conductor (18) formed on both surfaces thereof. A step (16) is formed on the lower surface of the dielectric substrate, which makes a spacing between the patch conductor and the ground conductor nonuniform in a direction of length of the patch conductor. By making nonuniform the spacing between the patch conductor and the ground conductor in the direction of length of the patch conductor, radiation efficiency and antenna gain are changed in that direction, resulting in asymmetrical directivity.