RFID readers such as synthesized-beam readers may be used to track RFID tags of interest. When a tag of interest is detected, a reader may choose to keep the tag of interest from entering a quiet state, which a detected tag may normally enter. Subsequently, the tag of interest can respond more frequently than a tag in the quiet state, allowing the reader to track any movement of the tag of interest and determine a tag trajectory. The reader may further use the determined trajectory to cooperatively-power the tag of interest.

An RFID-enabled retail carriage basket, which may be placed within a retail carriage or may be integrated into a retail carriage, such as a shopping cart. The RFID-enabled retail carriage basket may have a base with a near-field radio-frequency antenna, and sidewalls arranged around the perimeter of the base. RF-reflecting material may be attached to the lower part of the carriage basket, on the outside of the base and along the lowest parts of the sidewalls. RF-mitigating material may be attached to the remaining parts of the sidewalls. The RFID-enabled retail carriage basket may be connected to a host device, which may control scanning of the basket that may be performed by the antenna. If desired, the RFID-enabled retail carriage basket may be provided in the lower basket of a double-basket shopping cart and configured to scan both the upper and the lower basket with the antenna.

A system and method for reading a credential for an access system is provided. The system may include one or more readers, reader pickup coils, credential read heads, credential switches selectively connecting and disconnecting the reader pickup coil and its respective credential read head, and virtually real credentials. When a user presents a credential to a reader, the user's credential is read, and the appropriate virtually real credential is interrogated, and its indicium is transmitted to the reader. The system then grants the user access or no access depending on the indicium received.

A system and method for monitoring the inventory of a medical storage container such as a tray that has a required inventory of medical articles. An enclosure is used to isolate, scan, and take an inventory of the tray or other container of medical articles. The tray and each of the medical articles in the tray have RFID tags. The enclosure having a size differing from the size needed for a resonant frequency at the RFID frequency of operation of the tags. A probe is used to create a robust electromagnetic field standing wave of constructive interference in the enclosure and a program compares the scanned present inventory of the tray to the required inventory database and indicates any differences. Expired and recalled articles and substitutes for recalled articles are identified.

An inventory system for wirelessly taking inventories of mobile medical dispensing carts comprises an easily assemblable and disassemblable enclosure comprising interconnected electrically conductive walls to form a Faraday cage. The interior space defined by the walls is large enough to accept the mobile carts. RFID readers are placed within the enclosure directed at the mobile cart to excite and read the RFID tags disposed on the medical articles within the cart. The walls of the enclosure are flexible and one of the walls is rolled up and down to act as a door to the interior space. A host computer stores the inventory of the cart and compares it against a previous inventory existence for resupply purposes. The host computer also detects expired and recalled medical articles in the cart. If a recalled article is detected, the host computer determines if a substitute article exists.

Techniques are provided to estimate the location of an RFID tag using tag read information, such as a tag read count or a tag read rate, and an opportunity metric, such as an inventory cycle duration, inventory cycle rate, or inventory cycle count. A tag tracking system determines read information for a tag in a zone and an opportunity metric associated with the tag and the zone. The tag tracking system then computes a success rate based on the tag read information and opportunity metric, and uses the success rate to estimate the location of the tag.

A method and structure improves a reading efficiency for RFID tags located in a reading zone of a RFID reading apparatus. A structure is interposed between the RFID tag(s) and the RFID reading apparatus. The structure is essentially electrically non-conductive and comprises a network of RFID antennas. The network of RFID antennas network is positioned on the structure in a pattern whose periodicity in two dimensions is less than half an operating RFID wavelength, so as to create a three dimensional interferometric pattern with peaks of electromagnetic field intensities. The RFID reading apparatus or the at least one RFID tag is set in motion, relatively to one another. The at least one RFID tag is read by the RFID reading apparatus during the relative motion within the reading zone so that the three dimensional interferometric pattern shifts and thereby improves the reading efficiency.

A system and method for managing the contents of a medical storage container, such as a tray, that has an inventory of medical articles. A Faraday cage enclosure is used to isolate, scan, and inventory the container. The container and each of the medical articles in the container have a respective RFID tag. A processor is programmed to retrieve the inventory list for the container based on its RFID tag and compare the actual contents of the container according to their tags to the inventory list. The processor is also programmed to show the layout of the pockets of a tray and show an indicator of which pocket a particular medical article should be located.

An automatic data collection system tracks medical articles by providing a robust electromagnetic (EM) field within an enclosure in which the articles are stored. Respective data carriers, such as RFID tags, attached to each medical article respond to the EM field by transmitting unique data identified with each medical article. The use of probes for injecting the EM field into the enclosure results in a greater likelihood of activation of the tags and greater accuracy in detecting and tracking medical articles.

Disclosed is a system for electromagnetic interrogation of RFID transponders including at least one RFID terminal configured to emit an interrogation signal at a frequency F1, at least one RFID device referred to as repeater configured to receive the interrogation signal with frequency F1 and to repeat same towards at least one RFID transponder at the frequency F2, characterized in that the at least one RFID terminal includes at least one RFID reader configured to emit an interrogation signal with frequency F0 and at least one add-on RFID device configured to perform a frequency transposition from the frequency F0 to the frequency F1, the frequencies F0 and F1 being different.