Patent Application
20070159298
This invention relates to the field of electronic RFID shelf labels. In particular, the invention relates to an improved system and method for interrogating and updating electronic UHF RFID shelf labels.
A typical Radio Frequency Identification (“RFID”) system consists of a plurality of RFID tags and an interrogator for reading the RFID tags to obtain data (e.g., pricing information, color, size, etc.) and/or update the information contained within the tags. Each RFID tag contains a transponder with a digital memory chip that is given a unique electronic product code. The interrogator, typically an antenna packaged with a transceiver and a decoder, emits a signal activating the RFID tag so information contained within the digital memory chip may be read/updated.
The RFID tags can either be active or passive. Passive RFID tags have no internal power supply and utilize the minute electrical current induced in the antenna by the incoming RF signal to transmit a response. Due to their limited power, passive RFID tags typically respond to an interrogation with just an ID number or product code.
In contrast, active RFID tags have an internal power source which enables them to have a longer read range and larger memories. However, active RFID tags eventually expire and are more expensive to produce than passive RFID tags.
Currently, there are four kinds of RFID tags in common use: low frequency tags (125 to 134.2 kHz), high frequency tags (13.56 MHz), UHF tags (868 to 856 MHz), and microwave tags (2.45 GHz). Each kind of RFID tag is suited to a different kind of application. For example, passive UHF tags, in particular, are well suited for use as electronic shelf labels because the tags are inexpensive to produce and can be scanned at distances as great as 30 feet.
Recently, there have been many attempts to create an electronic shelf label system which is capable of interrogating and/or updating the RFID tags located on products in a store in warehouse. Most systems have focused on providing an infrastructure to directly connect the electronic RFID tags to the central computer system. In these systems, a plurality of RFID monitoring devices are distributed throughout the store or warehouse in a manner such that every RFID tag in the store can be scanned. Each of the RFID monitoring devices is in communication with a central controller which is used to verify the information contained within each RFID tag. The connection between the RFID monitoring devices and the central controller may be either a wired or wireless connection.
In general, this infrastructure has been difficult to create without causing other problems in the environment, or has been simply too expensive. Accordingly, there exists a need for a system for monitoring electronic shelf labels which is both inexpensive and simple to deploy.
In one exemplary embodiment of present invention, a system for interrogating and updating electronic shelf labels is provided. The system includes a plurality of products, wherein each product is equipped with an electronic shelf label and wherein each electronic shelf label stores information relating to the product, at lease one portable RFID device capable of scanning and updating the electronic shelf labels, a central controller which stores information about each of the products, and a wireless area network which allows for bi-directional communication between the portable RFID device and the central controller, wherein the information stored in the central controller is compared to the information stored in the electronic shelf labels as each electronic shelf label is scanned with the portable RFID device and wherein the portable RFID device updates the information stored in the electronic shelf label with the information from the central controller if the compared values are different.
The object of the present invention is to provide an electronic shelf tag system which is capable of interrogating and/or updating UHF RFID tags located within a store or warehouse using one or more RFID devices. The invention relies on the fact that UHF RFID tags can be reliably read at distances up to 30 feet by a simple battery-powered device. Instead of a fixed infrastructure for communications with the shelf tags, it is possible to have a portable device that will interrogate and update each of the electronic shelf tags. The scanning/updating functions may be performed by a store employee while engaged in other necessary activities, such as stocking shelves, organizing goods on the shelves (known as “leveling”), etc.
The portable RFID device may act as a bridge between a wireless LAN network so that the operation can be centrally controlled. Alternatively, the device could be self contained and have all the correct pricing information internally stored. In either case, a complete store wide verification and update can be performed in accordance with an exemplary embodiment of the present invention. Because the communication with the electronic shelf tag is bi-directional, it is possible to ensure that every tag in the store is interrogated and that it contains the correct information.
The foregoing objects, features, and advantages of the present invention will be apparent from the following detailed description of the preferred embodiments which makes reference to several drawing figures.
Throughout the Figures the same reference numerals and characters, unless otherwise stated, are used to denote like features, elements, components or portions of the illustrated embodiments. Moreover, while the present invention will now be described in detail with reference to the Figures, it is done so in connection with the illustrative embodiments.
In the following description of the preferred embodiments, reference is made to the accompanying figures which form the part thereof, and in which are shown by way of illustration of specific embodiments in which the invention may be practiced. It is to be understood that other embodiments may be utilized and structural and functional changes may be made without departing from the scope of the present invention.
Referring first to
Worker 105 who is typically an employee working within the store or warehouse, may carry a portable RFID device up and down the aisles of store 100 as he performs his normal daily duties, such as organizing the items located on shelves 101. The portable RFID device is preferably a battery-powered device which is capable of interrogating and/or updating the electronic shelf labels.
Circle 107 shows the scanning range of the portable RFID device. For example, if UHF RFID tags are utilized, circle 107 may have a radius as great as thirty feet. That is, the portable RFID device carried by worker 105 would be able to interrogated and/or update all UHF RFID tags located within a radius of thirty feet from worker 105. However, it should be obvious to one skilled in the art that more powerful portable RFID devices will eventually be manufactured, thus increasing the scanning range. Additionally, electronic shelf labels which have longer read distances may also be used in conjunction with the present invention.
As worker 105 traverses shelves 101, the electronic shelf labels located on products 103 within circle 107 are interrogated and/or updated by the RFID device. It should be obvious to one skilled in the art that multiple workers 105 could be equipped with portable RFID devices to increase the speed and/or number of times that each electronic shelf label is scanned or updated.
Referring next to
Central controller 205 is a preferably a server computer which contains master product database 209. Central controller 205 may either be located on-site or at a remote location. Master product database 209 preferably contains pricing information for each product 103 located in the store. However, it should be obvious to one skilled in the art that master product database 209 could contain any information about the different products 103 located in the store. For example, in an alternative embodiment, master product database 209 may contain information such as color, size, weight, expiration date, etc.
As each electronic shelf label 201 is interrogated by RFID device 203, its decoded value is sent to central controller 205 where it is compared with information store in master product database 209. In the event that the information in an electronic shelf label 201 and the master product database 209 is different, the central controller can send the correct information to RFID device 203 in order to update electronic shelf label 201. Thus, by utilizing the system of the present invention, a user only has to make changes to master product database 209 in order to update the information stored in all of the electronic shelf labels 201.
It should be obvious to one skilled in the art that the speed at which each electronic shelf label 201 is interrogated and updated can be accelerated by employing more than one RFID device 203. By increasing the number of RFID devices 203, the chance that any electronic shelf label 201 is missed is also reduced.
Now, referring to
While there have been described what are believed to be the preferred embodiments of the present invention, those skilled in the art will recognize that other and further changes and modifications may be made thereto without departing from the spirit of the invention, and it is intended to claim all such changes and modifications as fall within the true scope of the invention.
