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Typically, a company would install a portal reader at key points along a conveyor and then use passive UHF RFID tags to track parcels moving along the belt. Knowing the location of the specific reader that just read a given tag on a particular parcel would tell you the item’s location. If, for some reason, you needed to know the precise location of a parcel moving down a conveyor, you would have to use an active ultra-wideband (UWB) real-time location system.
UWB is a form of active RFID that overcomes multipath issues to locate a tag to within 10 centimeters (3.9 inches), or potentially less with more reader antennas. The issue with using UWB for this application is that the tags are fairly expensive since they utilize a battery to broadcast a signal. If a tag cost, say, $25 and you had millions of parcels to track, then the cost would be prohibitive.
There are overhead passive UHF RFID readers that can determine tags’ locations. However, I do not believe such systems would give you accurate location readings for tagged objects moving at a speed of 1 meter per second.
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