Abstract: A commodity information display apparatus includes a shelf on which a commodity is displayed, and a display unit for displaying the commodity information about the commodity. The commodity information about the commodity related to an RFID tag detected by an antenna and a read device is acquired in advance from a store computer and stored in a storage unit. When the commodity information is displayed, the information is acquired from the storage unit, and displayed on the display unit.

Abstract: An antenna unit includes a plurality of loop antennas; an impedance matching circuit common to the loop antennas; a switching circuit that switches high frequency connection between the impedance matching circuit and the loop antenna; and an antenna control circuit that controls to connect only one loop antenna among the loop antennas in a high frequency manner on the basis of a control signal from a reader.

Abstract: A connection adapter includes first interfaces, second interfaces for connection to communication devices connected to a radio packet communication network, and a conversion circuit performing mutual conversion between an input/output signal from or to high-level equipment and an input/output signal from or to the communication device. The conversion circuit receives or supplies from or to the high-level equipment a signal simulating the communication device connectable to the high-level equipment and receives or supplies from or to the communication device a signal simulating the high-level equipment connectable to the communication device.