Arrangement for, and method of, locating product tags by locating users who are operating mobile readers for reading the product tags

A user moves about a venue, and operates a mobile reader to read a product tag in a read zone of the mobile reader. An identifier, such as a user identity badge, is associated with the user to identify the user. A sensing system is deployed in the venue for sensing the location of the identifier. A host server associates the mobile reader with the identifier of the user operating the mobile reader, and determines a location of the product tag in the venue based on the read zone and the location of the identifier.

BACKGROUND OF THE INVENTION

The present disclosure relates generally to an arrangement for, and a method of, locating product tags associated with products in a venue, and, more particularly, to locating the product tags by locating users who are operating handheld, mobile readers for reading the product tags.

It is known to deploy a radio frequency (RF) identification (RFID) system in a retail, factory, or warehouse environment, or a like venue, for product locationing, product tracking, product identification, and inventory control. For example, in order to take an inventory of products associated with RFID product tags in a warehouse environment or venue, it is known to position a plurality of RFID tag readers at fixed, overhead locations in the venue, and then, to operate each such overhead reader, under the control of a network computer or host server, to transmit and receive RF signals over a relatively long, reading range, e.g., over twenty feet, to any such product tags to read their payloads. A multitude of product tags may be in the reading range of each reader. A specific location of any particular RFID-tagged product in the venue is typically determined by having the server process the payloads and capture data from a plurality of the overhead readers by using triangulation/trilateration techniques known in the art.

Although the known RFID system has been generally satisfactory, its performance could sometimes suffer and degrade when, for example, multiple RFID-tagged products are stacked closely together, thereby making any one individual product more difficult to isolate and read, and/or are positioned on metal shelving structures, or near walls, of the venue. In such cases, the RF signals are often reflected and/or scattered off these structures and walls along multiple paths, thereby reducing the capability of the readers of accurately locating the product tags. To help alleviate this performance degradation, handheld, user-operated, mobile, RFID tag readers are sometimes used in conjunction with the overhead RFID tag readers. The handheld, mobile readers typically have a shorter reading range, e.g., up to about ten feet, and since they can be brought more closely to, and targeted more directly at, individual products, a successful reading of each individual product is more likely, with a lesser likelihood that any RF signal will be reflected and/or scattered off walls and/or structures of the venue.

One drawback in using the handheld, mobile reader is that its location in the venue during reading of the product tags is not known, i.e., does not have a fixed position, and, therefore, although a product tag can typically be more accurately read by the mobile reader, the location of that product tag is likewise unknown. The art has proposed inferring the location of the product tag by locating the mobile reader. However, this requires the mobile reader to be specially configured and modified, and a special locationing system to be installed at the venue so that the modified mobile reader can be located and, in turn, so that the product tag and its associated product can be located relative to the mobile reader.

For example, it is known to deploy an ultrasonic locationing system in the venue for this purpose. The ultrasonic locationing system deploys a plurality of ultrasonic transmitters, e.g., speakers, preferably at fixed, overhead locations in the venue, and drives the speakers, under the control of the host server, to determine the location of any such mobile reader that contains an ultrasonic receiver, e.g., a microphone. Each ultrasonic speaker transmits an audio signal or ultrasonic energy in a short burst which is received by the microphone on the mobile reader, thereby establishing the presence and specific location of each mobile reader within the venue, again using triangulation/trilateration techniques known in the art. However, although the known ultrasonic locationing system has been generally satisfactory, its presence and installation add to overall system complexity and expense. In addition, the requirement to specially configure and modify the mobile reader also adds to system complexity and expense.

Accordingly, it would be desirable to reduce overall system complexity and expense, to avoid having to install and operate an additional locationing system such as an ultrasonic locationing system at a venue, to avoid having to specially configure and modify a mobile reader, and to accurately locate a product tag without having to first find the location of the mobile reader.

DETAILED DESCRIPTION OF THE INVENTION

One aspect of this disclosure relates to an arrangement for locating a product tag associated with a product in a venue, such as a retail, factory, or warehouse environment. The arrangement includes a mobile reader that is operated by a user in the venue, and that reads the product tag in a read zone that extends between the mobile reader and the product tag. An identifier, such as an identity badge, is associated, and is jointly movable in the venue, with the user. The identifier identifies the user. A sensing system is deployed in the venue, and is operative to sense the location of the identifier. A host server is operatively connected to the mobile reader and the sensing system. The server associates the mobile reader with the identifier of the user who is operating the mobile reader, and also determines the location of the product tag in the venue based on the read zone and the location of the identifier.

In one embodiment, the identifier includes a radio frequency (RF) identification (RFID) identifier tag, and the sensing system is an RFID system operative for locating the identifier by reading the RFID identifier tag on the identifier. In another embodiment, the identifier includes an ultrasonic receiver, and the sensing system is an ultrasonic locationing system operative for locating the identifier by transmitting an ultrasonic signal to the ultrasonic receiver on the identifier. In still another embodiment, the identifier includes a Wireless Fidelity (Wi-Fi) receiver, and the sensing system is a Wi-Fi system operative for locating the identifier by transmitting a Wi-Fi signal to the Wi-Fi receiver on the identifier. In yet another embodiment, the identifier includes a Bluetooth Low Energy (BLE) receiver, and the sensing system is a BLE system operative for locating the identifier by transmitting a BLE signal to the BLE receiver on the identifier. In an additional embodiment, the identifier includes an image, and the sensing system is a video system operative for locating the identifier by capturing the image on the identifier.

In a preferred embodiment, the sensing system is the above-described RFID system, and the identifier includes the above-described RFID identifier tag. In addition, it is preferred if the mobile reader is a handheld, portable, RFID tag reader, and if the product tag is an RFID product tag. In operation, the RFID tag reader radiates an antenna field pattern having a forwardly-extending front lobe that constitutes the aforementioned read zone in which the RFID product tag is contained, and a rearwardly-extending back lobe or back zone in which the RFID identifier tag is contained. Thus, when the mobile RFID reader reads the RFID product tag, it also simultaneously reads the RFID identifier tag in order to associate the mobile reader with the identifier of the user operating the mobile reader.

A further aspect of this disclosure is directed to a method of locating a product tag associated with a product in a venue. The method is performed by operating a mobile reader by a user movable in the venue to read the product tag in a read zone that extends between the mobile reader and the product tag; by associating an identifier with the user to identify the user, the identifier being movable with the user in the venue; by sensing the location of the identifier; by associating the mobile reader with the identifier of the user operating the mobile reader; and by determining the location of the product tag in the venue based on the read zone and the location of the identifier.

In accordance with this disclosure, a product tag is accurately located without having to first find the location of the mobile reader, and without having to install and operate an additional locationing system to locate the mobile reader, and without having to specially configure and modify the mobile reader. Instead, the user is located by his/her identifier that is carried and/or supported and/or worn by the user, and the location of the product tag is determined based on the location of the identifier and the read zone. The overall system complexity and expense have been reduced, while improving system performance.

Turning now to the drawings, reference numeral10inFIG. 1generally depicts a warehouse environment or venue in which products12, shown inFIG. 1as cuboid cartons for simplicity, are to be accurately located in accordance with this disclosure. As described below, a plurality of sensing network units30is mounted overhead, for example, on a ceiling14. Advantageously, the sensing network units30can be installed every twenty to eighty feet or so in a square grid. A network computer or host server16, typically locally located in a backroom at the venue10, comprises one or more computers and is in wired, wireless, direct, or networked communication with each sensing network unit30through a network switch18. The server16may also be remotely hosted in a cloud server. The server16may include a wireless RF transceiver that communicates with each sensing network unit30. For example, Wireless Fidelity (Wi-Fi) and Bluetooth® are open wireless standards for exchanging data between electronic devices. The server16controls each sensing network unit30.

As depicted inFIGS. 1-2, three of the sensing network units30can be used to locate an identifier26, such as an identity badge (seeFIG. 5), by triangulation or trilateration, as diagrammatically shown by dashed lines20. The identifier26is associated, and jointly movable, with a user24, e.g., by being supported and/or carried and/or worn by the user24, for example, by being suspended from a neck strap28. As described below, the identifier26can be any badge, token, garment or device capable of identifying the user24. The user24is any person, employee, operator, or associate authorized to operate a handheld, mobile reader22operative for reading product tags associated with the products12or items in the venue10.

The mobile readers22are preferably handheld, radio frequency (RF) identification (RFID) tag readers, but can also be handheld bar code symbol readers, phones, tablets, computers, or like data capture devices that are held and carried by the user24during his/her movement within the venue10. Each product12is preferably tagged with an RFID product tag, preferably a passive RFID tag for cost reasons, and, in some applications, each RFID product tag may be associated with a pallet or a container for multiple products12. The venue10may have any layout or configuration. As shown inFIG. 2, the venue10may have, for example, a plurality of shelving structures7and8separated by an aisle9in the venue10, and a plurality of items1-2can be mounted on the shelving structure7, and a plurality of other items3-6can be mounted on the shelving structure8.

The block diagram ofFIG. 3depicts different sensing systems that can be mounted in each sensing network unit30. One or more of these sensing systems can be operated to locate the identifier26. In one embodiment, the identifier26includes a radio frequency (RF) identification (RFID) identifier tag or chip60(seeFIG. 5), and the sensing system is an RFID system operative for locating the identifier26by reading the chip60on the identifier26. More particularly, the RFID system includes an RFID tag reader module32that has control and processing electronics that are operatively connected to a plurality of RFID antennas34, which are energized by the RFID module42to radiate an antenna field pattern. The RFID module42includes an RF transceiver operated, under the control of the server16, to transmit an RF signal to the chip60, and to receive an RF response signal from, the chip60, thereby interrogating and processing the payload of the chip60that is in its coverage reading range. The payload or captured target data identifies the chip60, and multiple sensing systems locate the identifier26.

In another embodiment, the identifier26includes an ultrasonic receiver or chip60, and the sensing system is an ultrasonic locationing system operative for locating the identifier26by transmitting an ultrasonic signal to the chip60on the identifier26. More particularly, the locationing system includes an ultrasonic locationing module36having control and processing electronics operatively connected to a plurality of ultrasonic transmitters, such as voice coil or piezoelectric speakers38, for transmitting ultrasonic energy to the chip60on the identifier26. The receipt of the ultrasonic energy at the chip60locates the identifier26. Each ultrasonic speaker38periodically transmits ultrasonic ranging signals, preferably in short bursts or ultrasonic pulses, which are received by the ultrasonic receiver, e.g., a microphone on the identifier26. The microphone determines when the ultrasonic ranging signals are received. The locationing module36, under the control of the server16, directs all the speakers38to emit the ultrasonic ranging signals such that the microphone on the identifier26will receive minimized overlapping ranging signals from the different speakers38. The flight time difference between the transmit time that each ranging signal is transmitted and the receive time that each ranging signal is received, together with the known speed of each ranging signal, as well as the known and fixed locations and positions of the speakers38on each sensing unit30, are all used to determine the position of the microphone on the identifier26, using a suitable locationing technique, such as triangulation, trilateration, multilateration, etc.

In still another embodiment, the identifier26includes a Wireless Fidelity (Wi-Fi) receiver or chip60, and the sensing system is a Wi-Fi system operative for locating the identifier26by transmitting a Wi-Fi signal to the chip60on the identifier26. More particularly, the Wi-Fi system includes a Wi-Fi network module40having control and processing electronics operatively connected to a plurality of Wi-Fi antennas42. The Wi-Fi signal is transmitted to the chip60on the identifier26. The receipt of the Wi-Fi signal at the chip60identifies the chip60, and multiple sensing systems locate the identifier26.

In yet another embodiment, the identifier26includes a Bluetooth Low Energy (BLE) receiver or chip60, and the sensing system is a BLE system operative for locating the identifier26by transmitting a BLE signal to the chip60on the identifier26. More particularly, the BLE system includes a BLE network module44having control and processing electronics operatively connected to a plurality of BLE antennas46. The BLE signal is transmitted to the chip60on the identifier26. The receipt of the BLE signal at the chip60identifies the chip60, and multiple sensing systems locate the identifier26.

In an additional embodiment, the identifier26includes an image62(seeFIG. 5), and the sensing system is a video system operative for locating the identifier26by capturing the image62on the identifier26. More particularly, the video system includes a video module48having camera control and processing electronics that is connected to a camera50for capturing the image62on the identifier26. The camera50is advantageously a high-bandwidth, moving picture expert group (MPEG) compression camera. The capture of the image at the camera50is processed by the server16to locate the identifier26.

It will be understood that each sensing network unit30need not have all or some of the above-described sensing systems, because any one sensing system will suffice. In the preferred embodiment, only the RFID system is employed to sense the location of the identifier26. As also shown inFIG. 3, a networking control switch52is connected to each module32,36,40,44,48, preferably by Power-over-Ethernet (PoE) cables, each PoE cable being operative to transmit electrical power and control data to and from the networking control switch52and each module32,36,40,44,48.

FIG. 4is similar toFIG. 2in that another user24is depicted as wearing the identifier26suspended from a neck strap28, and as holding and operating the mobile RFID tag reader22to read any RFID product tags located in a read zone54.FIG. 4also diagrammatically depicts an antenna field pattern radiated from the RFID tag reader22. In operation, the RFID tag reader22radiates an antenna field pattern having a forwardly-extending, front lobe that constitutes the aforementioned read zone54in which each RFID product tag is contained, and a rearwardly-extending back lobe or back zone56in which the RFID identifier tag or chip60is contained. Thus, when the RFID tag reader22reads the RFID product tag, it also simultaneously reads the chip60, thereby assisting the host server16in associating the mobile reader22with the identifier26of the user24operating the mobile reader22. To insure that the RFID identifier tag or chip60is read in the back zone56, this RFID identifier tag is preferably configured as a battery-assisted passive (BAP) tag. It is preferred that the RFID identifier tag or chip60be a single tag, although in some cases, it may be configured as two RFID identifier tags or chips.

The read zone54can be directional as shown, or omni-directional. The size of the read zone54can be fixed or variable, e.g., by modifying the magnitude or power level of the transmitted RF signal. As illustrated, the read zone54is generally elliptically shaped and has a major axis that extends away from the reader22to the product tag over a maximum distance or length58. The read zone54is three-dimensional and also has a maximum height/width in mutually orthogonal directions perpendicular to the major axis. The host server16determines the location of the RFID product tag in the venue based not only on the location of the identifier26, but also on the dimensions of the read zone54. Thus, once the identifier26is located, the position of the RFID reader22is inferred to be in the immediate vicinity of the identifier26, and the position of the RFID product tag is inferred to be within the maximum distance58of the read zone away from the RFID reader22. The location of the RFID product tag may be refined by reading the RFID product tag multiple times and/or by varying the power level of the transmitted RF signal, and averaging the results.

As previously stated, the identifier26can be any badge, token, garment or device capable of identifying the user24, and is not to be restricted only to the identity badge depicted inFIG. 5. The identifier26can be incorporated into a garment, such as a vest, hat, or other article of clothing; or can be incorporated into a badge clipped onto the user's shirt/blouse, pants/skirt, belt, etc; or can be incorporated into a wrist bracelet, necklace, etc. The identifier26can even be incorporated into an electronic device, such as a smartwatch, smartphone, or tablet, carried or worn by the user.

The flow chart ofFIG. 6depicts the operation of the method of this disclosure. In step70, the mobile reader22is operated by the user24in the venue10to read the product tag in a read zone that extends between the mobile reader22and the product tag. In step72, the identifier26is associated with the user24to identify the user24. The identifier26is jointly movable with the user24in the venue10. In step74, the location of the identifier26is sensed. In step76, the mobile reader22is associated with the identifier26of the user24operating the mobile reader22. In step78, the location of the product tag in the venue10is determined based on the read zone and the location of the identifier26.