Rfid tag communication device

A radio frequency identification (RFID) tag communication device, comprising:

• a first antenna configured to radiate first radio waves toward a conveyance path for a plurality of RFID tags such that a first communication area is formed along the conveyance path;
• a second antenna configured to radiate second radio waves toward the conveyance path such that a second communication area is formed along the conveyance path;
• a shield blocking part of the first radio waves such that first radio waves does not reach a portion of the conveyance path otherwise within the first communication area;
• a controller configured to:
• select a target RFID tag that becomes unreadable via the first antenna during conveyance of wireless tags along the conveyance path within the first communication area;
• and
• write data to the selected target RFID tag via the second antenna;
• a switch connected to the first and second antennas;
• and
• a tag reader/writer connected to the switch, wherein
• the controller is further configured to control the switch to selectively connect the tag reader/writer to the first or second antenna.

A wireless tag communication device, comprising:

• a first antenna configured to radiate first radio waves toward a conveyance path for a plurality of wireless tags such that a first communication available area is formed along the conveyance path where communication via the first antenna can be established with the wireless tags as the wireless tags pass along the conveyance path;
• a second antenna configured to radiate second radio waves toward the conveyance path such that a second communication available area is formed along the conveyance path where communication via the second antenna can be established with the wireless tags as the wireless tags pass along the conveyance path;
• a shield to block the first radio waves from reaching a portion of the conveyance path so as to form a communication unavailable area within the first communication available area;
• and
• a controller configured to:
• identify tag IDs of the wireless tags that are readable via the first antenna;
• select a target tag ID from among the identified tag IDs;
• and
• write information to the wireless tag corresponding to the selected target tag ID via the second antenna, wherein
• the controller selects the tag ID of the wireless tag for which the number of communication attempts via the first antenna exceeds a predetermined threshold.