Grouping transponders

Methods and systems of processing transponder signals received from transponders to identify the transponders are provided. A first signal including a first code and a first identifier may be received from a first transponder. The first identifier is written to the first transponder by an RFID writer when the first transponder is placed proximate to the RFID writer, and the first identifier is used to associate transponders with a first user. A second signal including a second code and the first identifier may be received from a second transponder. The first identifier is also written to the second transponder by the RFID writer when the second transponder is placed proximate to the RFID writer. The first and second transponders are associated with the first user based on receiving the first identifier from both the first and second transponders.

BACKGROUND

Many businesses, such as supermarkets, place barcodes on products for sale to identify the products at checkout. However, at checkout, each product barcode must be located, orientated to the barcode scanner, and then individually scanned by the barcode scanner. This process can sometimes cause significant delays and long checkout lines. Additionally, sometimes for large items, it is difficult to even find the attached barcode. Further, barcodes sometimes won't scan and thus, the cashier has to manually enter the code into the computer. Nonetheless, customers may get frustrated with long lines at checkout and decide not to purchase the items they came for originally, thereby causing the business to lose business.

SUMMARY

To address the above issues, an RFID system is provided which allows for scanning of multiple transponders (e.g., RFID tags) at the same time. Each of a plurality of users selects a different RFID writer. Each RFID writer has a unique identifier so that when a user selects items he is interested in, the RFID writer writes the unique identifier to items' transponders selected by the user. When the user is ready to check out, an RFID reader may read the transponders of the user-selected items simultaneously. Because the user's RFID writer writes an identifier that is different than other RFID writers, the RFID reader can distinguish between the user's selected items from other items (e.g., items from another user in the checkout line).

In one embodiment, a method of processing transponder signals received from transponders to identify the transponders is provided. A first signal including a first code and a first identifier may be received from a first transponder. The first identifier is written to the first transponder by an RFID writer when the first transponder is placed proximate to the RFID writer, and the first identifier is used to associate transponders with a first user. A second signal including a second code and the first identifier may be received from a second transponder. The first identifier is also written to the second transponder by the RFID writer when the second transponder is placed proximate to the RFID writer. The first and second transponders are associated with the first user based on receiving the first identifier from both the first and second transponders.

In another embodiment, an RFID reader may include an antenna to receive transponder signals, and a processing logic coupled to the antenna. The processing logic is configured to receive, from a first transponder, a first signal comprising a first code and a first identifier. The first identifier is written to the first transponder by an RFID writer when the first transponder is placed proximate to the RFID writer, and the first identifier is used to associate transponders with a first user. The processing logic is configured to receive, from a second transponder, a second signal comprising a second code and the first identifier. The first identifier is also written to the second transponder by the RFID writer when the second transponder is placed proximate to the RFID writer. The first and second transponders are associated with the first user based on receiving the first identifier from both the first and second transponders.

In yet another embodiment, a communication system is provided. The communication system may include a first RFID writer and a second RFID writer. The first RFID writer may be configured to be associated with a first user and to write a first identifier to transponders that come into a range of the first RFID writer. The second RFID writer may be configured to be associated with a second user and to write a second identifier to transponders that come into a range of the second RFID writer. A RFID reader may receive, from a first transponder, a first signal comprising the first identifier; receive, from a second transponder, a second signal comprising the first identifier; and receive, from a third transponder, a third signal comprising the second identifier. The RFID reader may group the first transponder and second transponder as being associated with a first user due to being associated with the first identifier. The RFID reader may associate the third transponder with a second user due to being associated with the second identifier.

DETAILED DESCRIPTION OF THE EMBODIMENTS

Examples of the invention include various methods and apparatuses for writing a unique identifier to a set of transponders (e.g., radio-frequency identification (RFID) tags) to associate the set of transponders with a specific user (e.g., a customer at a store). This allows users to have their respective associated items be distinguishable from each other. For example, a customer may enter a store and select a personal RFID writer. The customer then selects items the customer wants to purchase and places such items proximate to the customer's RFID writer. The RFID writer then writes a unique identifier to the transponder of each item. This unique identifier is only associated with the customer's RFID writer to distinguish the customer's selected products from other item in the store. In this regard, when a customer “checks out” at the store, all items with transponders having the customer's associated unique identifier will be purchased by the customer. Other items that inadvertently get scanned that may have a different identifier are immediately known to not have been selected by the customer and thus, the customer may not be charged for such item.

Examples of the invention find ready application in settings where RFID tags are placed on products for sale. These settings may include, for example, supermarkets, retail stores, hardware stores, and any other stores that have products that typically are scanned individually at checkout. It should be understood that, while examples of the present invention are discussed herein with regard to shopping by a customer, the present invention may not be so limited and could be applied to various other applications.

FIG. 1illustrates a method50of operating an RFID system with RFID writers in accordance with one embodiment. At52, a user enters a location and selects a first RFID writer. The location may include a plurality of RFID writers to accommodate a plurality of users. Each user selects a different RFID writer so that no user has the same RFID writer, and because each RFID writer is configured to write a different identifier to transponders, each user is associated with a unique identifier.

It should be understood that the term “user” may be any person or device which selects items that have transponders. In one embodiment, a user may be a customer in a store.

Additionally, it should be understood that a transponder may be any device which is configured to transmit a code to a wireless reader, such as an RFID reader. In one embodiment, a transponder is an RFID tag, which may be used to automatically identify objects. RFID tags are generally placed on items using an automatic tag applicator, and then the items are identified by one or more RFID readers.

Regardless, the first RFID writer selected by the user is placed proximate to the user. In one embodiment, the first RFID writer is placed on a shopping cart/basket associated with the user. The first RFID writer may be placed in a central location of the shopping cart or basket, such as on a base portion of the shopping cart or basket, so that the range of the RFID writer does not significantly extend beyond the limits of the shopping cart or basket. This allows for each RFID writer to only be associated with one shopping cart or basket and not overlap with other RFID writers. In other embodiments, the RFID writer may be placed at any other location, such as other locations in the shopping cart or basket (e.g., on the handle), on the user (e.g., on the user's key chain), or any other location proximate to the user so that the user can browse and select items throughout the location/store while being in possession of the RFID writer.

At54, a user selects an item (e.g., products for sale in a store) and places the item proximate to the user's RFID writer (i.e., the first RFID writer). Each selected item may have a transponder attached thereto or associated therewith. A user can select the item by moving the item from a first location (e.g., a store shelf) to the user's shopping cart or basket (or other location) so that the item's transponder is proximate (e.g., within one to twelve inches) to the first RFID writer of the user. Regardless, when the user places the transponder of the item proximate to the RFID writer (e.g., within a range of one to twelve inches), the first RFID writer then writes the unique identifier to the transponder. The transponder then not only has the code identifying specifics of the item, but also the unique identifier which is associated with the user. The item is then associated with the user through the item's transponder.

As mentioned above, a location or store can have multiple users and RFID writers as long as each RFID writer is configured to write a different identifier for each user.FIG. 2illustrates an example of a system100employing multiple RFID writers104according to one embodiment. At least three users108are illustrated as shopping in a store102. Each user108,108′,108″ has selected three RFID writers104,104′,104″, respectively, and a shopping cart or basket114. A first RFID writer104is associated with a first customer108, a second RFID writer104′ is associated with a second customer108′, and a third RFID writer104″ is associated with a third customer108″. Each RFID writer is configured to write a unique identifier to transponders106when the transponders are selected by the customers and placed proximate to the RFID writer (e.g., within the range112of the closest RFID writer), as discussed above. This allows a customer to select items when shopping (or performing some other function) and have the transponders of the customer's items have a common unique identifier that is different than the identifiers written to transponders for other customers. In this regard, when a user “checks out” at the store, all items with transponders having that user's unique identifier will be purchased by the user, but not any other items.

It should be noted that inFIG. 2, the RIFD writer may be located at multiple locations on the shopping cart or basket114. For example, the first RFID writer104is placed on top of a central portion the shopping cart or basket. This allows the customer108to place the object next to first RFID writer104and then drop the object in the cart/basket. In another embodiment illustrated inFIG. 2, the second RFID writer104′ is placed on top of the cart/basket114and on a portion of the cart/basket114that is closest to the user108′. This allows the user108′ to have RFID writer104′ within a short, proximate distance relative to the user108′ when the user108′ is shopping. In a third embodiment illustrated inFIG. 2, the third RFID writer104″ is placed at a central location of the cart/basket. In this way, the range112of the third RFID writer104″ does not substantially extend outside of the cart/basket114. Additionally, the range112may be such that a user simply places the item in the cart/basket and the RFID writer automatically writes to the transponders placed therein. It should be understood that the RFID writer104may be placed at any other location in the cart/basket114or at some other location on another object/person.

Referring back toFIG. 1, at56, the first RFID writer writes a first identifier to the transponder when the transponder becomes proximate to the first RFID writer, such as when the transponder is placed within range112of the first RFID writer. As mentioned above, each RFID writer has a range whereby the RFID writer can write to a transponder. In one embodiment, range112of each RFID writer may be between one inch to twelve inches. Additionally, the frequency of each RFID writer may be between 50 KHz to 5 MHz. In one embodiment, the frequency of each RFID writer may be 125 KHz. Each RFID writer may not write the unique identifier to any transponders which are outside the RFID range. Operation of the RFID writer is illustrated inFIG. 3, in accordance with one embodiment.

FIG. 3illustrates a diagram of a system of an RFID writer104writing to transponders106within the RFID writer range112of a user108, according to one embodiment. RFID writer104includes an antenna, a transceiver314, a read/write module316, and a unique identifier318stored in memory. As illustrated inFIG. 3, transponder106′ is within RFID range112, while transponders106′,106″ are outside of range112. The transponders ofFIG. 3include memory206where a code associated with the transponder is stored. The code of each transponder identifies the item it is attached thereto. For example, a transponder attached to a shirt has a code which identifies the shirt and other data associated with the shirt, such as the shirt price, an SKU number, and/or any other information about the shirt. The transponder code is capable of being modified to add or change the data therein. In one embodiment, a unique identifier may be added as a prefix to the code of the transponder by the RFID writer. In another embodiment, the unique identifier does not modify the code but instead is saved as an additional code in the transponder. Regardless, when an RFID reader queries the transponder, the transponder may transmit back to the RFID reader both the code and the unique identifier.

The antenna of the RFID writer is designed to transmit a signal to a transponder which instructs the transponder to write the unique identifier to the transponder, such as a prefix to the previously-stored code. The transponders may be “passive” RFID tags or “active” RFID tags. Passive RFID tags are a type of transponder that does not contain their own power source or transmitter. When radio waves from the RFID writer reach the transponder's antenna, the energy is converted by the transponder's antenna into electricity that can power up the microchip in the tag (typically via inductive coupling). The passive RIFD tag is then able to receive and store the unique identifier to memory at the RFID tag by modulating the RFID reader's electromagnetic waves. “Active” RFID tags have their own power source and transmitter. The power source, usually a battery, is used to run the microchip's circuitry and to broadcast a signal to an RFID reader. Passive RFID tags do not have as great a range as active RFID tags, but it should be understood that either type of transponder may be employed in the present application.

The read/write module316may be employed by the transponder to receive the unique identifier318from the RFID writer104and uses the inductive energy from the RFID writer to write the unique identifier to the transponder when the transponder is within the RFID writer range112. For example, inFIG. 3, transponder106′ has been placed within the RFID writer range112and thus, memory206′ is written with unique identifier318of RFID writer104. Transponder106″ is outside of the RFID range112and thus, the RFID writer104does not write to such transponder. Similarly, transponders106in the shopping cart or basket114but outside of range112may not be actively written to while in the shopping cart or basket. However, prior to placing transponders106in the shopping cart, transponders106may have been placed proximate to the RFID writer104for a predetermined time period. As such, transponders106in the shopping cart or basket114have identifier318written to memory206.

The unique identifier remains on the transponders106so that an RFID reader (302ofFIG. 4) can read the transponder identifier318and thus, remains on the transponder until another RFID writer writes over the identifier or if the transponder's memory206is erased.

It should be understood that the RFID writer104may be a RFID reader/writer that is configured to not only write to transponders but may also read the transponders.

Referring back toFIG. 1, at58, the user may continue to add items to his shopping cart or basket114. For each additional items selected by the user, steps54and56may be completed, namely that the item is selected and placed proximate to the RFID writer so the writer can write the same unique identifier318to the transponders of the additional items. This allows the same user (i.e., the first user) to have a cart or basket114of items with transponders having the same unique identifier (i.e., the first identifier). No other users (i.e., a second user, third user, etc.) in the store or location have items with transponders having an identifier (i.e., a second identifier, third identifier, etc.) other than the first identifier.

Steps60-72are discussed below in conjunction withFIG. 4.FIG. 4illustrates a system300for reading transponders having a unique identifier according to an embodiment. The system300may include an RFID reader302and at least one transponder106with the unique identifier.FIG. 4illustrates four transponders106each having the same unique identifier318written thereto.

At step60ofFIG. 1, the RFID reader302receives the unique identifier318(i.e., the first identifier). In one embodiment, an antenna of the RFID writer104wirelessly transmits the unique identifier318to the RFID reader302. Upon receipt, the transceiver308of the RIFD reader302may route the first identifier318to the processor310which then saves the first identifier318into memory312. All other identifiers associated with other users that are stored in memory312are erased. In this regard, the RFID reader302identifies the first identifier318as associated with the first user that is currently “checking out.” In another embodiment, a cashier or other person320may manually enter the first identifier318to the RFID reader302or a computer301associated therewith. Regardless, the first identifier318is stored into memory312and may be accessed by logic306.

Referring back toFIG. 1, at step62, the RFID reader302reads one of the transponders106in the user's shopping cart or basket114. When an item having a transponder is placed near the RFID reader, the transponder receives electromagnetic signals from the RFID reader. In response to these electromagnetic signals, the transponder generates radio waves with a pattern identifying the transponder. The RFID reader's antenna receives these radio waves and transmits them to the RFID tag reader module304, which interprets the radio waves to determine the data that the radio waves contain. Such data may include a code indicating the identity of the object as well as any identifiers appended to the code (e.g., as a prefix). The RFID reader may communication the received code with a database322connected to the RFID reader and/or computer301via a network321. The database may include the codes related to the objects which the transponders106are attached. When the RFID reader reads the codes from the transponders106, the RFID reader may look up the codes in the database. In one embodiment, the database may be resident on the RFID reader.

At step64ofFIG. 1, the RFID reader determines if the data received from a first transponder includes an identifier. To determine this, for example, the RFID reader determines if the data has a prefix attached to the transponder code. This identifier prefix may have a starting data string which would indicate to the RFID reader (at the RFID tag reader module304) that an identifier is included in the transmission. The identifier is then extracted from the data transmission by being the data located between the prefix starting data string to a prefix termination data string according to one embodiment. The extracted identifier then may be transmitted to logic306of the RFID reader302, which compares the extracted identifier from data transmitted from the first transponder with the first identifier received from the RFID writer. If the RFID reader logic306determines that the transponder contains the first identifier, the method50may proceed to step66; otherwise, the method50may continue to step68and may optionally provide an alert to the RFID reader operator.

At step66ofFIG. 1, if the RFID reader's logic306determines from the comparison that the extracted identifier and the first identifier stored in the RFID reader memory312are the same, the RFID reader determines that the first transponder contains the first identifier318and thus, is associated with the first user. The first transponder is then assigned an “approved” status so that the item associated with the first transponder is added to a purchasing transaction. Data associated with the first transponder, such as the identity of the associated item, the price of the associated item or any other information about the item associated with the first transponder, may be transmitted to computer301(e.g., a cash register computing device) for further processing. For example, the item may be added to the checkout session so that the store can add the item to the purchase transaction list.

At step68, the RFID reader (or computer301) may mark the first transponder as having been read so that it is not read again by the RFID reader. To that end, the RFID reader may store the transponder identification code to memory312and/or transmit the transponder identification code to computer301. This way, if the RFID reader accidentally scans the transponder again, the RFID reader recognizes that the transponder identification code is one that has already been scanned and thus, will not duplicate the item for the purchase transaction during the checkout session of the user.

Steps62through68may be repeated for all transponders within the RFID range of the RFID reader302that have not been read by the RFID reader. Thus, at step70, the RFID reader302determines if any transponders have not been read by the RFID reader, and if not, the method50may return to step62. Otherwise, the RFID reader302may indicate (e.g., via an audible or visual alert, via a message to computer301, etc.) that the scanning for the checkout session for the first user has completed. The RFID reader302may transmit a list of items that were scanned and marked as “approved” to computer301.

Thus, in light of the above, transponders, such as RFID tags, may be read when in a user's shopping cart or basket114so that each individual item associated with the transponders do not have to be individually handled by a checkout personnel. Transponders may be scanned by the RFID reader and the ones having the user's assigned identifier written thereto are then added to the purchase transaction.

Any patents and applications and other references noted above, including any that may be listed in accompanying filing papers, are incorporated herein by reference. Aspects of the invention can be modified, if necessary, to employ the systems, functions, and concepts of the various references described above to provide yet further embodiments of the invention.

While certain aspects of the invention are presented below in certain claim forms, the inventors contemplate the various aspects of the invention in any number of claim forms. For example, while only one aspect of the invention may be recited as a means-plus-function claim under 35 U.S.C sec. 112, sixth paragraph, other aspects may likewise be embodied as a means-plus-function claim, or in other forms, such as being embodied in a computer-readable medium. (Any claims intended to be treated under 35 U.S.C. §112, 6 will begin with the words “means for”.) Accordingly, the inventors reserve the right to add additional claims after filing the application to pursue such additional claim forms for other aspects of the invention.