Rfid enabled warehouse management system and method

A method for determining locations of load units in a warehouse having a warehouse management system (WMS) controlling an automated storage system in which inventory items are stored in a plurality of load units that are storable at a plurality of storage locations within the storage system, said method comprising:

• storing individual load units containing one or more inventory items at respective storage locations within the storage system, wherein each load unit comprises a radio frequency identification (RFID) tag having a unique RFID identifier;
• enabling an RFID reader disposed at the storage system and in communication with the WMS, wherein the RFID reader is operable to read and recognize RFID tags present in the storage system and to determine spatial coordinate and/or orientation information of recognized RFID tags;
• attempting to read and recognize RFID tags of load units present in the storage system with the RFID reader;
• the WMS receiving any spatial and orientation information for each load unit RFID tag that is recognized from the RFID reader;
• for every load unit RFID tag that is recognized, the WMS determining a global position of the respective load unit relative to a reference location within the storage system;
• and
• storing the global position of each load unit in an inventory database of the WMS.

An RFID enabled material handling system for an automated warehouse, said material handling system comprising:

• a warehouse management system (WMS) comprising a computer configured to control said material handling system;
• an automated storage and retrieval system (ASRS) comprising a storage rack having a plurality of rack levels defining a plurality of storage locations each configured to support a load unit containing one or more inventory items;
• and
• a plurality of radio frequency identification (RFID) readers positioned proximate various portions of said ASRS, each RFID reader having a known location relative to said ASRS and said RFID readers in communication with said computer and configured to read and recognize an RFID tag coupled to a load unit that is present in the ASRS and in sufficient proximity to a respective one of said RFID readers, each of said RFID reader configured to communicate information associated with a recognized RFID tag to said computer;
• and
• said computer operable to determine a location of a load unit relative to said ASRS utilizing information of the load unit's RFID tag, as provided by the respective RFID reader that read and recognized the tag, and the known location of that respective RFID reader relative to the ASRS.