Method and apparatus for communicating with RFID devices coupled to a roll of flexible material

A method of testing the RF communication operation of a plurality of RF transponders, comprising the steps of:

• providing a sheet characterized by first and second opposite faces and a thickness;
• mounting on the sheet a plurality of RF transponders, wherein each transponder includes a transponder RF antenna;
• positioning a first test fixture section having a first RF shield so that the first RF shield abuts the first face of the sheet;
• positioning a second test fixture section so as to abut the second face of the sheet, wherein:
• the second test fixture section includes a plurality of RF shields,
• each RF shield in the second test fixture section is in the shape of a cup having a mouth abutting said second face of the sheet,
• the first and second test fixture sections so that each RF shield in the second test fixture section encircles a corresponding one of the transponder RF antennas so as to form, in combination with the first RF shield, a closed cavity that completely surrounds and encloses said corresponding transponder RF antenna except where the thickness of the sheet separates the first RF shield from the mouth of said RF shield in the second test fixture section, and
• said thickness is sufficiently small so that the first and second RF shields prevent any RF signals within the cavity from radiating outside the cavity;
• positioning within each cavity a corresponding test fixture RF antenna;
• transmitting an RF signal from each test fixture antenna;
• detecting a response by each at least one transponder to the RF signal transmitted by its corresponding test fixture antenna;
• and
• subsequently removing each transponder from proximity to the first and second test fixture sections and the test fixture RF antennas, so that no shielding obstructs each transponder RF antenna from sending and receiving RF radiation at any angle.

A test fixture for testing the RF communication operation of an RF transponder which is mounted on a sheet which extends beyond the perimeter of the transponder, the RF transponder having an antenna for receiving RF signals, comprising:

• first and second RF shields, the second RF shield being in the shape of a cup having a mouth;
• an alignment mechanism for positioning the first and second RF shields to abut opposite sides of the sheet so that the mouth encircles the transponder antenna and so that the combination of the first and second RF shields forms a closed cavity completely surrounding and enclosing the transponder antenna except where the sheet separates the two RF shields, wherein the distance by which the sheet separates the two RF shields is small enough to prevent any RF signals within the cavity from radiating outside the cavity;
• and
• a test fixture RF antenna mounted within the cavity.

A test fixture for testing the RF communication operation of a plurality of RF transponders mounted on a sheet, each RF transponder having an RF antenna, comprising:

• a first test fixture section including a first RF shield;
• a second test fixture section including a plurality of RF shields each of which is in the shape of a cup having a mouth;
• an alignment mechanism for positioning the first and second test fixture sections to abut opposite sides of the sheet so that each RF shield in the second test fixture section encircles a corresponding one of the transponder antennas so as to form, in combination with the first RF shield, a closed cavity that completely surrounds and encloses said corresponding transponder RF antenna except where the sheet separates the first RF shield from the mouth of said RF shield in the second test fixture section, wherein the distance by which the sheet separates the first RF shield from each RF shield of the second test fixture section is small enough to prevent any RF signals within each cavity from radiating outside that cavity;
• and
• a test fixture RF antenna mounted within each cavity.

A method comprising the steps of:

• providing, to a material handling apparatus, a plurality of flexible radio frequency identification (RFID) devices coupled to a continuous roll of flexible material;
• advancing to a first region a first RFID device while coupled to the roll of flexible material, the first RFID device comprising a dipole antenna coupled to an integrated circuit;
• transmitting a first wireless interrogation signal to the first RFID device within the first region;
• and
• receiving a first wireless reply signal from the first RFID device within the first region, wherein RF energy associated with wireless communication with the first RFID device is sufficiently isolated to the first region to prevent communication interference with a separate RFID device coupled to the roll of flexible material.

A system comprising:

• a material handling apparatus:
• a plurality of flexible RFID devices removably attached to a continuous roll of flexible material mounted on the material handling apparatus, each of the plurality of flexible RFID devices comprising a respective dipole antenna coupled to a respective integrated circuit and disposed on a respective flexible polymer substrate;
• a first RFID device disposed in a first region, the first RFID device being removably attached to the continuous roll of flexible material, the first region configured to prevent a first adjacent RFID device of the plurality of flexible RFID devices from interfering with RF communication with the first RFID device in the first region;
• and
• a first interrogation antenna disposed within the first region.

A system comprising:

• a material handling apparatus configured to receive a continuous roll of flexible material including a plurality of flexible RFID devices;
• a motor to advance individual ones of the plurality of RFID devices separately into a first region;
• and
• a first interrogation antenna disposed within the first region to communicate with the individual ones of the plurality of RFID devices while coupled to the roll, wherein RF signals are isolated to the first region to prevent confusion with other RFID devices coupled to the continuous roll.

A method comprising:

• providing a system containing a plurality of flexible radio frequency identification (RFID) labels coupled to a continuous sheet of flexible material, each of the plurality of flexible RFID labels comprising a respective antenna coupled to a respective integrated circuit disposed on a respective, flexible polymer film;
• advancing a first RFID label of the plurality of RFID labels to a wireless communication region of the system;
• transmitting a first wireless signal to the first RFID label while the first RFID label is in the wireless communication region of the system and is coupled to the sheet, the first wireless signal being effectively isolated to the wireless communication region of the system to prevent interference by a separate RFID label external to the wireless communication region and coupled to the continuous sheet;
• and
• attaching the first RFID label to an article for tracking in accordance with an article tracking process.

A method comprising:

• providing an apparatus with a continuous sheet of flexible material including a plurality of flexible RFID devices;
• advancing an RFID device of the plurality of RFID devices into a wireless communication region of the apparatus while the RFID device is coupled to the continuous sheet of flexible material;
• wirelessly communicating, via an interrogation antenna, with the RFID device in the wireless communication region in a manner that prevents communication between the antenna and an adjacent RFID device external to the region and coupled to the continuous sheet of flexible material;
• and
• attaching the RFID device to a respective article for tracking in accordance with an article tracking process.

A system comprising:

• a first reel;
• a second reel;
• an interrogator antenna configured to transmit RF signals having a wavelength;
• two plates separated by a distance of less than the wavelength;
• a roll of flexible material extending from the first reel, between the two plates, to the second reel, wherein the roll comprises a plurality of RFID devices;
• and
• a motor to align a first RFID device of the plurality of RFID devices between the two plates, wherein the RF signals from the antenna are isolated from an adjacent RFID device of the plurality of RFID devices.