Abstract: The location of unmodified wireless assets in a wireless communication network may be identified using time differences of arrivals of a communication sequence at different network receivers. Time-stamping devices may include correlator circuits in parallel with signal decoders to time-stamp communication sequences. Cellular wireless networks may be frequency-multiplexed to increase spatial time-stamping density. Tags may be attached to passive assets to provide location identification information to network devices. Locations of assets broadcasting standard 802.11 radio frequency structures may be identified. Noise inherent in correlating a communication sequence may be reduced by using a selected correlation function.

Abstract: The location of unmodified wireless assets in a wireless communication network may be identified using time differences of arrivals of a communication sequence at different network receivers. Time-stamping devices may include correlator circuits in parallel with signal decoders to time-stamp communication sequences. Cellular wireless networks may be frequency-multiplexed to increase spatial time-stamping density. Tags may be attached to passive assets to provide location identification information to network devices. Locations of assets broadcasting standard 802.11 radio frequency structures may be identified. Noise inherent in correlating a communication sequence may be reduced by using a selected correlation function.

Abstract: An electronic display tag system. The system has an electronic display tag including a display for displaying at least one of pricing data and product identification data, the display having bistable character elements or bistable pixels. The display tag has a decoder logic unit for decoding received programming data and for updating the display based on the programming data, the programming data being received wirelessly. The display tag also has a wireless transceiver, the wireless transceiver for converting a power inducing signal transmitted wirelessly to the display tag into electrical power, the electrical power used by the decoder logic unit to update the display.

Abstract: An electronic identification system comprising a transmitter for generating an electromagnetic excitation signal, one or more portable transponders for storing variable identification data, and for transmitting an information signal containing the identification data upon entering the field. Transmission of the information signal is independent of the excitation signal in both time and frequency. A radio frequency receiver is provided for receiving the information signal and in response generating output signal representing the variable identification data contained in the information signal.

Abstract: An identification system comprises an interrogator which transmits an interrogation signal to a plurality of transponders, each of which is arranged automatically to reply by means of a first coded identification signal stored in the transponder and modulated onto a carrier wave transmitted by the transponder. The interrogator receives and checks the reply signal. In the event of there being a plurality of transponders within range and broadcasting reply signals simultaneously, the interrogator receives corrupted reply signals. The interrogator therefore retransmits the reply signals to the transponders and each transponder checks the retransmitted reply signal with its first coded identification signal. In the event of correspondence the transponder discontinues transmission and in the event of non-correspondence the transponder continues transmission.