TECHNICAL FIELD

The subject application generally relates to radio frequency identification (“RFID”) tags and, more specifically, to hands free stock picking management using RFID tags.

BACKGROUND

Radio frequency systems, such Radio Frequency Identification (“RFID”) systems and Near Field Communication (“NEC”) systems, allow suitable transceivers to query and receive messages from nearby radio frequency tags. Such tags can allow users to perform inventory management functions without having to manually count individual articles.

Radio frequency tags can operate in various ranged such as, but not limited to, the High Frequency (“HF”) range and Ultra High Frequency (“UHF”) range. RFID tags often include a chip that is coupled to at least one suitable antenna, such as an antenna for RFID systems that operate in a desired range. The RFID tag receives power when excited by a nearby electromagnetic field emitted the resonant frequency of the RFID tag. Once the chip has received sufficient power, (e.g., 10 μW), the chip turns on and transmits a coded return signal or message via the coil antenna.

SUMMARY

According to certain embodiments, a radio frequency identification (“RFID”) based inventory system includes an RFID reader for interrogating RFID tags on inventory, and an RFID barrier that is configured to substantially inhibit interrogation of RFID tags associated with active inventory until a picked item from the active inventory is moved away from the RFID barrier. The RFID based inventory system determines that an item is picked when there is an increase in the number of responses to the RFID interrogation.

In certain other embodiments, a method includes interrogating RFID tags associated with inventory by an RFID reader that is in proximity to inventory, and inhibiting the interrogation of an active inventory item until an item in picked and removed from proximity of the RFID barrier.

According to yet other embodiments, a method of hands-free item picking from active inventory includes transmitting a first interrogation signal, inhibiting transmission of the first interrogation signal to active inventory by an RFID barrier, receiving a plurality of first responses from substantially only the replenishment inventory, transmitting a second interrogation signal, receiving a second plurality of responses, and determining that an item was picked from active inventory using one or more of when the second plurality of response is greater in number than the first plurality of responses; an RSSI of one of the first responses is not substantially below the RSSI of other responses; and responses are received from both a picked item and a non-inventory asset such as a forklift.

