主权项 |
1. A conveyor system for processing items on which radio frequency identification tags are disposed, said system comprising:
a conveyor that conveys items through a path of travel, each item having at least one respective radio frequency identification tag disposed thereon; an antenna disposed with respect to the path of travel so that the antenna radiates radio frequency signals into an area through which the items pass; and circuitry in electrical connection with the antenna so that the circuitry drives the antenna to emit the radio frequency signals into the area, wherein the circuitry is selectable between at least two operative states, wherein, in a first said operative state, the circuitry drives the antenna to emit the radio frequency signals in a first radiation pattern, wherein, in a second said operative state, the circuitry drives the antenna to emit the radio frequency signals in a second radiation pattern that is different from the first radiation pattern, and wherein said first and second radiation patterns are respective volumes within which the radio frequency identification tags receive and emit responses to the radio frequency signals. |