Patent ID: 6362737
Filing Date: 2002-03-26
Classification: G01S,G06K,G08B,H01Q

Abstract:
A method of determining the identification of at least one radio frequency identification device of a plurality located within communication range of an antenna, the method comprising:determining a frequency for interrogating, wherein determining comprises: transmitting via the antenna, wherein transmitting is performed in a relatively narrow band manner with respect to receiving; operating for a duration a squelch circuit that is coupled to the antenna; receiving via the antenna after lapse of the duration to provide a received signal, wherein receiving is performed in a relatively wide band manner with respect to transmitting; determining a property of the received signal; and determining the frequency for interrogation in accordance with the property, wherein determining the frequency comprises: comparing the property to a limit; and if the comparison is unfavorable, ignoring receipt of the received signal; interrogating to attempt to determine an identity of a device of the plurality; and repeating the determining and interrogating until each device of the plurality has been given at least one opportunity to be identified.