Patent ID: 6917290
Filing Date: 2005-07-12
Classification: G01S,G06K,G08B

Abstract:
1. A method of monitoring a plurality of wireless transmitters within a monitored area, comprising: (a) transmitting a signal from at least one of the plurality of wireless transmitters; (b) receiving the signal transmitted from said at least one of the plurality of wireless transmitters by at least one of a plurality of receiving devices; (c) scanning the received signal for a signal modulating code; (d) detecting the signal modulating code within the signal; and (e) determining a location of said at least one of the plurality of wireless transmitters based upon the signal modulating code detected and an identifier for the at least one of the plurality of receiving devices that received the signal; wherein the signal modulating code includes a common code that identifies a group of wireless transmitters that includes said at least one of the plurality of wireless transmitters and a unique code that uniquely identifies said at least one of the plurality of wireless transmitters; and wherein the common code of the signal modulating code is used to determine whether said at least one of the plurality of wireless transmitters is within an alert zone restricted to the group of wireless transmitters and the unique code of the signal modulating code is used to determine the location of said at least one of the plurality of wireless transmitters.