This disclosure describes RFID tags configured to fracture when heated, such as when exposed to threshold levels of electromagnetic energy. In some instances, the RFID tags include materials that expand when heated for the purpose of stressing metal antenna traces of the RFID tags. When under stress from these expansion materials that bond to the antennas (e.g., thermoplastics), these antennas may fracture, thus lessening the risk that the dangerous arcing will occur from the electromagnetic energy, such as when an item and corresponding tag are placed in a microwave oven.

A method of manufacturing a smartcard may include providing a flexible smartcard circuit, forming conductive extension members on and extend away from the flexible circuit from a high melting point solder material, and laminating the flexible circuit to form a smartcard body. A cavity is then milled in the smartcard body to expose the ends of the extension members, and a contact pad is inserted into the cavity and electrically connected to extension members using a low melting temperature tin-bismuth solder using ultrasonically soldering, so as to avoid heat damage to the card body.

In some embodiments, a radio frequency identification (RFID) system may include at least one Ultra High Frequency (UHF) antenna component, a conductive loop having a largest dimension that is smaller than the wavelength of radiation transmitted at a Microwave Frequency (MW). The conductive loop may define a gap and an RFID chip may be electrically coupled to the conductive loop. The conductive loop may be configured to be resonant at an Ultra High Frequency (UHF) and less resonant at Microwave Frequency (MW). The antenna component may be selected from the group consisting of a dipole antenna, a monopole antenna, a loop antenna, or a slot antenna.

A radio frequency (RF) sensing device in an assembly is adapted to wirelessly communicate with a remote transceiver. The sensing device includes a substrate; an antenna disposed on the substrate; an electronic circuit disposed on the substrate and electrically coupled to the antenna; a heating element electrically coupled to the electronic circuit for heating a target area; and a sensing element thermally coupled to the heating element for sensing a temperature of the heating element. The RF sensing device is configured to wirelessly receive a power and provides the power to the heating element.

Disclosed are pre-cure RFID-enabled bead labels based on an RFID inlay construction consisting of an aluminum antenna etched on to a high temperature resistant polyimide film that is connected to an integrated memory circuit positioned on the surface of the polyimide film. This RFID inlay being further inserted into an overall label construction having a plurality of layers that include, for example, a plurality of polyester layers and a plurality of high temperature resistant adhesive layers that bond/adhere layers together, the plurality of layers further protecting and insulating the RFID inlay while the label is bonded to the external bead (or sidewall) of a tire. The compositions/devices disclosed herein can be used for electronic identification when applied on rubber-based articles (e.g., tires) prior to being subjected to stress related to the vulcanization process and normal use of this article during the manufacturing process.

A radio frequency (RF) sensing device in an assembly is adapted to wirelessly communicate with a remote transceiver. The sensing device includes a substrate; an antenna disposed on the substrate; an electronic circuit disposed on the substrate and electrically coupled to the antenna; a heating element electrically coupled to the electronic circuit for heating a target area; and a sensing element thermally coupled to the heating element for sensing a temperature of the heating element. The RF sensing device is configured to wirelessly receive a power and provides the power to the heating element.

A high temperature radio frequency identification (RFID) tag component is disclosed that includes a base member made from a polyimide material and an attached radio frequency identification element. The high temperature radio frequency tag component is adapted for attachment to goods, inventory items, and/or assets that are at an elevated temperature, or to an inventory item or asset that is within an environment at an elevated temperature above 400? F.

A temperature-sensing RFID device includes an RFID chip and an antenna electrically coupled thereto. The RFID chip includes a temperature sensor, while the antenna is adapted to receive energy from an RF field and produce a signal. A shielding structure and/or a thermally conductive or absorbent structure may be associated with the RFID chip. The shielding structure is oriented so as to be positioned between at least a portion of the RFID chip and an outside environment and configured to shield the temperature sensor from at least one environmental factor capable of affecting a temperature sensed by the temperature sensor of an article to which the RFID device is secured. The thermally conductive or absorbent structure is oriented so as to be positioned between at least a portion of the RFID chip and the article and configured to enhance thermal coupling between the temperature sensor and the article.

A temperature-sensing RFID device includes an RFID chip and an antenna electrically coupled thereto. The RFID chip includes a temperature sensor, while the antenna is adapted to receive energy from an RF field and produce a signal. A shielding structure and/or a thermally conductive or absorbent structure may be associated with the RFID chip. The shielding structure is oriented so as to be positioned between at least a portion of the RFID chip and an outside environment and configured to shield the temperature sensor from at least one environmental factor capable of affecting a temperature sensed by the temperature sensor of an article to which the RFID device is secured. The thermally conductive or absorbent structure is oriented so as to be positioned between at least a portion of the RFID chip and the article and configured to enhance thermal coupling between the temperature sensor and the article.

A distributed antenna system including a plurality of remote antenna units, a passive element coupled to at least one of the remote antenna units and an RFID system located proximate the passive element. The RFID system includes processing circuitry and measurement circuitry and the processing circuitry is configured for receiving an interrogation signal and processing the interrogation signal and providing a response. The response includes data associated with a measurement made by the measurement circuitry.