Patent attributes
A portable container for one or more articles each tagged with a respective Radio Frequency Identification (RFID) transponder, the container comprising a detector device for detecting removal and/or placement of RFID-tagged articles in the container; a power supply for supplying electrical power to the detector device; an activation means operable to cause the detector device to detect a reference list of RFID-tagged articles located in the container; a verification means operable by movement of the container to cause the detector device to detect RFID-tagged articles located in the container and to signal deviation from the reference list; and a signal means for transmitting signals from the detector device to a user. The detector device may transmit an article absent signal and/or an unknown article signal. The detector device may comprise an external antenna configured to detect RFID-tagged articles outside the container.