Wearable RFID Sensor Tags With Priority Data Forwarding

Commonly used RFID protocols are widely accepted because they are inexpensive and easy to implement. However, the associated low transmit power and narrow bandwidth typically result in coarse local-ization estimates. Often it is desirable to know the precise location of assets without reverting to an entirely different and more expensive protocol. Additionally, many industrial and other applications may desire technology that confirms the mating of components. This new program-mable sensor tag technology facilitates both precise localization and mating confirmation in-part by allowing the RFID sensor tag to become a type of distributed low-cost reader. To determine a tag attachment, this innovation utilizes a fixed location RFID sensor tag that incorporates a receptacle node to measure an electrical “influence” through resistance, capacitance, inductance, etc. Assets for which localization is desired are outfitted with “influence tags” – devices that produce a set of distinguishable responses when placed in the receptacle region of the RFID sensor tag. Mating or connections are confirmed when electrodes from an influence tag become attached to matching electrodes on a sensor tag’s receptacle node. Information obtained by the RFID sensor tag is stored in its local memory bank through which a dedicated reader can retrieve influence tag information. Potential applications exist for this technology where specific assets need to be precisely located and/or confirmation is needed when two parts have been correctly connected or attached. This RFID tag technology allows the retrieval of inventory status information in an energy efficient manner from inexpensive, small form factor hardware. Robotic retrieval of assets can be more easily facilitated with this innovation.

With a form factor close to a deck of playing cards, the system interrogator has custom software to interface with and service a population of sensor tags at the required data rates. Each EPCglobal C1G2 sensor tag uses incident interrogator energy to charge its small integrated circuit (IC), which reads an internal memory bank, encodes identification data, and uses that information to modulate and backscatter a reply to the interrogator using reflected interrogator energy. Two tag interfaces allow the attached processor to power the reading/writing of data to the tag memory and then allows the interrogator to power the reading of the tag memory data. When neither of the two interfaces are engaged, the RFID IC is completely powered down. Reading and writing tag memory consumes relatively little power compared to the power draw of active transmitter/receiver protocols like Bluetooth, Zigbee, and Wi-Fi. Compared to passive sensing protocols, this wireless instrumentation system enables sampling of a larger population of tags without the computational burden associated with surface acoustic wave (SAW) sensing. RFID-Enabled Wireless Instrumentation technology allows the RFID interrogator to write data through the interface of a sensor tag memory bank using only interrogator power. With only minimal cost to the sensors power budget, the microcontroller unit can read that data out over the serial interface. The sensor can transmit and receive data at no effective cost to its small coin cell battery power supply. This technology is readiness level (TRL) 8 (actual system completed and "flight qualified" through test and demonstration) and the innovation is now available for your company to license. Please note that NASA does not manufacture products itself for commercial sale.

The RFID Tag with Long Range and Wide Coverage Capabilities technology allows a RFID tag to direct a RFID reader beam signal back in the direction of arrival. This technology requires no added power to provide telemetry for long range readers by using multiple beams instead of one narrow beam signal. Each of the predetermined number of beams is typically associated with a unique identification number to derive bearing information. This innovation is suited for IC-based RFID tags as well as Surface Acoustics Wave (SAW) tags, which are useful for extreme environments. The technology improves the ability to obtain telemetry (quantity, location, or sensor information) without GPS over a distant range. When the tag reports its identification, it also provides angular information to the source, which makes this technology useful for navigation and mapping applications. Because the technology provides an estimated angle between the signal antenna and the surface of each tag, the technology is able to triangulate the position of a mobile item identified with a RFID tag. The same innovation can be integrated to a RFID reader in order to enhance its range and distribute power to passive tags. The innovation has commercial applications in construction, oil and gas, seaport/harbor management, Internet of Things (IoT) and many more industries.

Passive Smart Container system comprises four major components: RFID circuits embedded in or around the container, an antenna and RF distribution system, and an interrogator/reader. The system uses passive RFID circuits placed on a bulk item container to track consumption and quantify items as the items are removed, added or replaced in the container. The antenna is strategically integrated with the lid or elsewhere in or around the container and is constantly coupling RFID signals to/from the RFID circuits. The circuits reply with information regarding the fill level in the container. A processor connected to the reader/interrogator can infer the fill level according to which RFID circuits respond and the magnitude and phase of the returned signals. The technology is compatible with the EPCglobal Class-1 Generation-2 RFID standard. This setup can be modified to track all kinds of items, large and small, making this technology suitable and applicable to an array of commercial fields. RFID is a disruptive technology that has made a large impact on several industries, especially in supply chain and asset management. Passive Smart Container is well positioned to tap into this growing market. Its ability to account for discrete items as well as liquids and bulk goods that were deemed impossible or impractical to tag makes this technology relevant for an array of applications and industries.

Current RFID readers, such as the EPC Global Class 1 Gen 2, are limited by narrow bandwidth restrictions, maximum transmit power, and a limited number of RF ports, which results in relatively coarse ranging resolution and accuracy, limited techniques for localization, and limited antenna functionality. Some of the currently available solutions, such as using larger antennas or adding switched multiplexers, often result in unacceptable cost, volume, aesthetics and mass penalties. The Agile RFID Antenna System integrates a frequency multiplexer into the RFID reader antenna system to provide greater antenna functionality without requiring additional reader RF ports, resulting in improvements in reader-tag communications read accuracy, read range, and localization. The Agile RFID Antenna System is at a TRL 8 (Technology has been proven to work in its final form and under expected conditions) and has been used on the International Space Station to support logistics management and it is now available for your company to license and develop into a commercial product. Please note that NASA does not manufacture products itself for commercial sale.