Patent ID: 6992564
Filing Date: 2006-01-31
Classification: G06K

Abstract:
1. A system for tracking portable devices comprising: a transmitter transmitting wireless inquiries to a plurality of portable devices; a receiver receiving replies to the inquiries from the portable devices; a memory arrangement storing identifier data corresponding to the portable devices, the identifier data including status information; a processor coupled to the memory arrangement and to the receiver, the processor retrieving from each reply, reply identifier data uniquely identifying a particular one of the portable devices which generated the reply and comparing the reply identifier data to the stored identifier data; and a portable device control system coupled to the processor and controlled based on the comparison of the stored identifier data to the identifier data retrieved from the replies, wherein, when the reply identifier data matches the stored identifier data the status information corresponding to the portable device is updated on the memory and, when the reply identifier data does not match the stored identifier data, the portable device control system provides an indication that the portable device is unregistered.