Patent ID: 8193481

Claim:
A method for assembling output data generated by at least one sensor unit having a local clock and linked to a data communication network with corresponding data representing sensed location on an article moving at a known speed or position/time profile along a travel path intersecting a sensing field associated with said sensor unit, said method comprising the steps of: i) transmitting reference time data through said data communication network; ii) receiving said reference time data at said sensor unit; iii) comparing said reference time data with local time data generated by said local clock substantially when said reference time data is received at said receiving step; iv) producing timestamp data in accordance with a result of said comparing step; v) causing said local clock to update its local time data according to said timestamp data; vi) associating updated time data generated by said local clock with sensor output data upon generation thereof; and vii) assembling said sensor output data with the corresponding sensed location data according to said associated updated time data.