Patent ID: 7380723

Claim:
A method of monitoring object movement, the method comprising: attempting to read an object identifier of an object in a first reading area, resulting in a plurality of first null read counts for falling to read the object identifier of the object in the first reading area; reading the object identifier of the object at least one time in the first reading area; determining a time the object entered the first reading area using at least one first timestamp from the at least one time the object identifier was read in the first reading area, wherein the at least one first timestamp is immediately preceded by one of the plurality of first null read counts; and determining a time the object exited the first reading area using the at least one first timestamp from the at least one time the object identifier was read in the first reading area, wherein the at least one first timestamp is immediately followed by another of the plurality of first null read counts; attempting to read the object identifier of the object in a second reading area resulting in a plurality of second null read counts for failing to read the object identifier of the object in the second reading area; reading the object identifier at least one time in the second reading area; determining a time the object entered the second reading area using at least one second timestamp from the at least one time the object identifier was read in the second reading area, wherein the at least one second timestamp is immediately preceded by one of the plurality of second null read counts; and determining a time the object exited the second reading are using the at least one second timestamp from the at least one time the object identifier was read in the second reading area, wherein the at least one second timestamp is immediately followed by another of the plurality of second null read counts; and determining a direction of movement of the object based on at least some of the determined times the object entered or exited the first or second reading areas.