Battery Powered Wireless Transceiver Having LPRF Component and Second Wake Up Receiver
Patent Number:  7,209,771

Abstract:   A wireless transceiver includes a low power radio frequency (LPRF) component that powers down to conserve energy and powers up in response to a signal; and a second receiver that provides the signal in response to receipt of a radio frequency broadcast. The broadcast is targeted to activate particular transceivers by including, in the broadcasts, identifications such as class designations, in which case the transceivers power up and form networks. A transceiver may include one or more identifications and may include a unique identification of the transceiver itself. The LPRF component may be a Bluetooth radio, but the overall transceiver itself only draws about 10 to 15 .mu.A while actively awaiting and screening for a targeted broadcast.

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