Patent ID: 7573366
Filing Date: 2009-08-11
Classification: G06K

Abstract:
1. A method, comprising the steps of: detecting a first trigger event using a trigger device, the trigger device including a trigger sensor and a trigger tag; listening on a predetermined radio frequency band by an interrogator for an activation signal, wherein the activation signal is generated by the trigger tag, the activation signal including a unique identifier of the trigger tag; receiving the activation signal; validating that the activation signal was received from an associated trigger tag; and activating the interrogator into an interrogation mode upon validation of the activation signal, wherein prior to receiving the activation signal the interrogator only awaits receiving the activation signal from the trigger tag and is incapable of interrogating a radio frequency tag, and wherein after the interrogator is in the interrogation mode the interrogator interrogates the radio frequency tag and does not interrogate the trigger tag.