HK1189979B - Simultaneous programming of selected tags - Google Patents

Description

Simultaneous programming of selected tags

Technical Field

The present invention relates to radio frequency identification (RFID) tags, and more particularly to methods and apparatus for writing data to such tags.

Background Art

Radio Frequency Identification (RFID) is a technology that involves the use of signals in the radio frequency (RF) portion of the electromagnetic spectrum to uniquely identify tags. An interrogating transmitter (e.g., an interrogator, programmer, or reader) can interrogate (read) information from a wireless tag by sending commands to the tag and receiving a response. Some interrogators (programmers) can program the tag's memory in addition to reading the tag's response.

There is a need to program multiple groups of tags in the most efficient way possible. Programming time is particularly important when dealing with thousands of tags (e.g., tags on products in a warehouse). Large numbers of tags should be programmed in the shortest possible time, especially if the tags are in large batches (e.g., a container full of products with tags that need programming). However, existing technologies have limitations, especially when trying to program a large group of tags in a short period of time.

It is possible to produce tags with programmable memory for storing data (e.g., serial number, model, and other object characteristics). An interrogator (programmer) can initialize the tag's memory based on individual application requirements. For example, just before the tag is applied to the product packaging, the manufacturer of a given product can encode a unique identification number on the tag. In other cases, more data is programmed into the tag's memory. For example, a television manufacturer that uses tags to track televisions in the supply channel may also want to specify the style, model, color, size, and/or other details of their televisions to each tag. With rewritable tags, data can be changed, added, or deleted at various points in the tag's life cycle. Unfortunately, writing to a large number of tags, especially to very low-cost passive tags, may take a relatively long time, depending on the tag's programming method.

One way to program tags is to program each tag individually. However, power must be provided to each tag during the time period when the memory is being programmed. Memory programming for passive RFID tags requires a relatively long programming interval during which the reader transmits the energy required to program the tag's memory. The time required to program a tag's memory may be as long as ten microseconds or more. In inventory management applications, such as tag systems used in warehouses, thousands of tagged objects may be within the RF field of a single reader, which may have a radius of several meters. For example, a single pallet of tagged objects may have more than one hundred boxes, each containing dozens of tagged objects.

Another method of programming tags is to broadcast a write command to all tags in range, programming the same data to all tags in range. One limitation of broadcasting to all tags in range is that it is not possible to specify specific tags and write only to those tags. Taking a broadcast write as an example, all tags in range will receive the broadcast command and write according to the broadcast command. Another limitation of broadcasting to all tags is that when multiple tags respond after programming is completed, the data written to each individual tag cannot be verified. For example, an interrogator that issues a broadcast write command to ten tags will receive ten responses to the command. Write responses sent at the same time will conflict and become difficult to decipher to the interrogator. In addition, the interrogator cannot program unique data specific to each tag in the group with a broadcast command. For example, a broadcast write writes the same data to all tags that receive the command.

Another method of programming tags is to use a write intent flag to inform the tag that a programming command will be sent. In order to write data to a tag using this method, the tag must first be programmed with the write intent, which can also take up to ten microseconds. After the write intent is saved to memory, a simultaneous write can be initiated. However, because writing the write intent often takes the same amount of time as programming the tag with the final data to be written to memory, this process is not very efficient. In addition, the write intent flag needs to be verified before writing can begin, and the write intent flag must be cleared after writing is complete. Therefore, the write intent flag has inherent inefficiencies that extend the time it takes to program multiple tags.

There is a need to efficiently write data to wireless tags, especially when multiple tags need to be programmed in a short period of time.

Summary of the Invention

In one embodiment, a method and apparatus for simultaneously programming tags are provided for efficiently programming multiple tags simultaneously.

In one embodiment, the interrogator performs an inventory on a population of Tags to identify a group of Tags that are individually designated for programming. In one embodiment, the interrogator sets a "being addressed" state for each Tag in the designated group of Tags. The "being addressed" state is used to prepare the Tags for incoming simultaneous programming commands.

In one embodiment, the data to be programmed is transferred to each designated Tag in a group of Tags. In one embodiment, the programming interval is shared by multiple Tags all writing their data simultaneously.

In one embodiment, the simultaneous program command is separated into data and address commands sent to a specified tag, and a program interval command that triggers data writing in multiple tags. In one embodiment, data, addressing, and program interval are sent to a group of specified tags in a single command.

BRIEF DESCRIPTION OF THE DRAWINGS

The present invention is illustrated by way of example and not limitation in the figures of the accompanying drawings in which like references indicate similar elements.

FIG1 illustrates one embodiment of an identification system including an interrogator and a plurality of RF tags.

FIG. 2 illustrates an example of one implementation of a tag that may be used with at least one embodiment of the present invention.

FIG. 3 illustrates an example of an RF tag according to one embodiment of the present invention.

FIG4 illustrates a flow chart representation of one embodiment of a method for simultaneously programming individually addressed data to each Tag in a group of Tags.

FIG5 illustrates a flow chart representation of one embodiment of a method for simultaneously programming a group of designated Tags with the same data.

FIG6 illustrates a flow chart representation of one embodiment of a method for implementing tags that participate in simultaneous programming.

DETAILED DESCRIPTION

The following description and drawings are illustrative of the invention and are not to be construed as limiting the invention. Many specific details are described to provide a complete understanding of the invention. However, in some instances, to avoid obscuring the description of the invention, well-known or conventional details are not described. The term "coupled" as used herein may mean a direct coupling or an indirect coupling via one or more intervening components. A reference to one embodiment of the present disclosure is not necessarily a reference to the same embodiment; such a reference means at least one.

Figure 1 illustrates an example of a tag programming system 100 that includes an interrogator 101 and a plurality of tags 131, 133, 135, ..., and 139. In one embodiment, the interrogator 101 interrogates a programmer and a reader in one device. In one embodiment, the tag programming system uses a reader-talks first RFID system that uses passive or semi-passive active backscatter transponders as tags. Incorporating batteries into tags is an extended feature to facilitate longer read ranges; however, the use of batteries does require certain tradeoffs, such as higher cost, limited life, larger form factor, heavier weight, and end-of-life disposal requirements. Therefore, tags 131-139 can have batteries or not. It will be appreciated that different types of tags can be mixed in a system where the interrogator interrogates tags with batteries and tags without batteries. There are at least four types of tags that can be used with the present invention:

(I) A tag that has no energy source on board other than that obtained from the tag's antenna and includes a one-time programmable memory capable of storing the tag's identification code, and may include factory-programmed memory, (II) A tag that has no energy source on board other than that obtained from the tag's antenna, but is capable of writing, erasing, or rewriting data to non-volatile memory in the tag when powered by an interrogator; this type of tag may also include a one-time programmable memory, and the tag's identification code may be in any of these memories. (III) A tag that has a small battery that provides power to the circuitry in the tag. This type of tag may also include non-volatile memory that also stores the tag's identification code or other data, as well as other types of memory, such as factory-programmed memory and write-once memory, and (IV) A tag that is capable of communicating with other tags or other devices.

Interrogator 101 typically includes a receiver 119 and a transmitter 123, each coupled to an I/O (input/output) controller 117. Receiver 119 may have its own antenna 121, and transmitter 123 may have its own antenna 125. Those skilled in the art will appreciate that transmitter 123 and receiver 119 may share the same antenna. Receiver 119 and transmitter 123 may be similar to conventional receiver and transmitter units found in existing interrogators. In North America, receivers and transmitters typically operate in a frequency range of approximately 900 MHz. In other embodiments, this range is approximately 2400 MHz. However, it will be appreciated that the operation of the RFID system disclosed herein is not dependent on a specific operating frequency. The receiver and transmitter are coupled to I/O controller 117, which controls the reception of data from the receiver and the transmission of data (e.g., commands) from transmitter 123. The I/O controller is coupled to bus 115, which is in turn coupled to microprocessor 113 (or processing logic) and memory 111. There are various possible implementations of the processing system represented by elements 117, 115, 113, and 111 that can be used in interrogator 101. In one embodiment, interrogator 101 may include processing logic coupled to bus 115. The processing logic can include a microcontroller, a finite state machine, or a logic array. In one implementation, microprocessor 113 is a programmable microcontroller, such as an 8051 microcontroller or other well-known microcontroller or microprocessor (e.g., an ARM microprocessor), and memory 111 includes dynamic random access memory and a memory controller that controls the operation of the memory. Memory 111 may also include non-volatile read-only and/or rewritable memory for storing data and software programs. Memory 111 typically contains programs that control the operation of microprocessor 113, as well as data used during the processing of tags, such as in the interrogation of tags. In one embodiment described further below, memory 111 includes a computer program that causes microprocessor 113 to send programming commands to the transmitter via the I/O controller and to receive responses from the tags via receiver 119 and via I/O controller 117. In one embodiment described further below, memory 111 includes instructions for creating and maintaining a queue or list of tags to be programmed. Interrogator 101 may also include a network interface 127, such as an Ethernet interface, that allows interrogator 101 to communicate with other processing systems via network 129. Network interface 127 may be coupled to bus 115 so that it can receive data, such as a list of tags identified from an interrogation of memory 111, from microprocessor 113 or from memory 111.

In one embodiment, interrogator 101 implements noise cancellation using a directional coupler and a reflection circuit. The directional coupler electrically couples a predetermined amount of a signal at one port to another port. The reflection circuit provides variable attenuation and a variable phase shift of the transmitted signal to generate a cancellation signal. This cancellation signal is added to the received signal to cancel or reduce unmodulated reflections of the transmitted signal.

FIG2 illustrates an example of one implementation of a tag that can be used with at least one embodiment of the present invention. Tag 200 includes an antenna 201 coupled to a receiver and demodulator 205 and to a backscatter modulator 209. A correlator and controller unit 207 is coupled to the receiver and demodulator 205 and to the backscatter modulator 209. The specific example of a tag shown in FIG2 can be used in various embodiments in which memory for maintaining data between commands is maintained in the tag and in which bit-by-bit (or larger blocks of data) correlation occurs in the tag. Receiver and demodulator 205 receives signals via antenna 201 and switch 203, demodulates the signals, and provides these signals to correlator and controller unit 207. To control the operation of the tag, commands received by receiver 205 are passed to a controller in unit 207. Data received by receiver 205 is also passed to control unit 207; in the embodiments described below, this data may include parameters for the commands. Backscatter modulator 209, under the control of control unit 207, modulates the input impedance of the tag corresponding to a response or other data to interrogator 101 via antenna 201. Those skilled in the art will appreciate that the impedance modulation of the chip to antenna 201 will result in a change in reflection at the interrogator that can be demodulated to extract the data transmitted by the tag.

In one embodiment of the present invention, the tags are designed with features such as a small integrated circuit (IC) area to allow for low cost, small memory, and less precise timing requirements. In one embodiment, atomic transactions are used to minimize tag state storage requirements. However, in other embodiments, other tag designs can be used. Furthermore, it should be understood that the methods for simultaneous programming of designated tags according to embodiments of the present invention can also be used in other similar situations.

FIG3 illustrates an example of an RF tag according to one embodiment of the present invention. In one embodiment, a VLC (very low cost) tag 300 includes an antenna 301 and an integrated circuit (IC) 303 connected together. The IC implements a command protocol and contains an identification code for the tag, which can be an Electronic Product Code (EPC ^™ ) that complies with a tag data standard, such as the tag data standard published by EPCGlobal's Tag Data Standards Working Group. Antenna 301 receives an interrogation signal and, in response to a modulated signal generated by IC 303, reflects the interrogation signal back to interrogator 101. Tag IC 303 can include an RF interface and power supply 311, a data detector and timing circuit 313, a command and control 315, a data modulator 317, and a memory 319. In one embodiment, command and control 315 includes static logic that implements simultaneous programming according to an embodiment of the present invention.

In one embodiment, the RF interface and power supply 311 converts RF energy into the DC power required for tag IC 303 operation and provides modulation information to the data detector and timing circuit 313. Alternatively, power can be provided by a battery or harvested power source. The data detection and timing block 313 demodulates the reader signal and generates timing and data signals used by the control logic 315. The RF interface also provides a means for coupling the tag modulated signal to the antenna for transmission to the interrogator 101. The data detector and timing circuit 313 demodulates the interrogator 101 signal and generates timing and data signals used by the command and control logic 315. The command and control logic 315 coordinates all functions of the tag IC 303. The command and control logic 315 may include state logic to interpret data from the interrogator 101, perform necessary internal operations, and determine whether the tag has responded to the interrogator 101. The command and control logic 315 implements multiple tag states and communication protocols according to the embodiments described below. The tag memory 319 may contain the EPC ^™ code of the product marked with the VLC tag. The tag memory 46 may contain a unique identification code or a non-unique identification code. The tag memory may also contain a checksum that may be used for error detection. The data modulator 317 translates the binary tag data into a signal that is then applied to the RF interface 311 and then transmitted to the interrogator 101. In one embodiment, the signal applied to the RF interface 311 is transmitted via the antenna 301.

The design and implementation of a tag can be characterized by layers. For example, the physical and environmental layers characterize the mechanical, environmental reliability, and manufacturing aspects of the tag; the radio frequency (RF) transmission layer characterizes the RF coupling between the reader and the tag; and the communication layer characterizes the communication/data protocol between the reader and the tag. Various different implementations of tags located at different layers can be used with embodiments of the present invention. It should be understood that the implementation of tags is not limited to the examples shown in this specification. Different tags or communication devices can use the methods of embodiments of the present invention to communicate as needed for the target application.

In one embodiment of the present invention, the tag can be manufactured via a fluid self-assembly process. For example, an integrated circuit can be manufactured from multiple other integrated circuits in a semiconductor wafer. If possible, the integrated circuit will include all the necessary logic for a specific RF tag, excluding antenna 301. Therefore, all the logic shown in tag 300 will be included on a single integrated circuit and manufactured together with similar integrated circuits on a single semiconductor wafer. Each circuit is programmed with a unique identification code, and the wafer will then be processed to remove each integrated circuit from the wafer to create a block suspended in the fluid.

The fluid is then spread on a substrate, such as a flexible substrate, to create a discrete RF tag. The receiving area on the substrate receives at least one integrated circuit, which can then be connected to an antenna on the substrate to form an RF tag.

As described above, it is advantageous to program the tag in the most efficient way possible. One bottleneck in tag programming is the time it takes to commit data to memory. Committing data to memory can take up to ten microseconds or more, depending on the tag design, to continuously provide power to the tag.

Pre-programmed tags

In one embodiment, the tag memory includes logically separate and different blocks. In one embodiment, the tag memory is divided into a reserved memory, a user memory, an EPC memory, and a TID memory. If a password is implemented in the tag, the reserved memory contains a deletion and or access password. The user memory allows user-specific data storage. The EPC memory contains EPC data used to identify the object to which the label is affixed. In one embodiment, the TID memory is a read-only memory that is pre-loaded with a unique tag ID before being distributed from the tag manufacturer. The tag ID in the TID memory can be a unique number for uniquely identifying a tag and the object to which the label is affixed. In other embodiments, in addition to the aforementioned blocks or in place of them, the tag memory includes another type of memory block.

A buyer or user of a tag may want to program the tag memory block based on specific usage requirements. For example, a manufacturer of televisions may want to program their manufacturer's name, television model, color, size, and other identifying characteristics into the tag before using it to mark and track their products.

In one embodiment, one or more portions of the tag memory are preprogrammed by the tag manufacturer before the tag is sent to the end user (e.g., before storage in a warehouse, a product manufacturer uses the tag in a supply chain, or other users). In one embodiment, the tag is preprogrammed with one or both of a unique serial number and a unique tag ID. The unique serial number can be incorporated into the product number or EPC. In addition to or in place of the unique serial number, the unique tag ID can be used to uniquely identify the tag or associated object. In one embodiment, the unique tag ID is programmed into the TID memory area and the unique serial number is programmed into the EPC memory area. Preprogramming the serial number and tag ID by the tag manufacturer can reduce the total amount of programming required by the end user. For example, Company XYZ wants to program specific identifying features into the tag (e.g., product color, model number, and other features of their products). Company XYZ has a large number of products with the same features. Without preprogrammed tags, Company XYZ would have to spend the necessary time to individually program each tag with a unique serial number or other unique identification, as well as the product color and model number. By utilizing the label manufacturer's pre-programming, Company XYZ only needs to program their product color and model number into each label, speeding up their overall time to fully program their labels. In this example, for a large number of products, the color and model number are the same, and Company XYZ will program many labels with the exact same color and model number. Because the labels that Company XYZ receives from the label manufacturer are pre-programmed with at least one unique identifier, only the identical features (e.g., color and model number) need to be added to the label data. In the case where the manufacturer pre-programs unique labels, the end user can program the same data (e.g., color and model number) for a group of labels at the same time and avoid writing unique data to each label. In one embodiment, using a simultaneous programming operation discussed further below, unique data (e.g., a serial number or a unique label ID) is programmed into each label at the same time.

Tag Inventory

In one embodiment, the interrogator 101 counts the current tag population before sending the simultaneous programming command. Performing a count of the tag population is useful in determining the serial number, tag ID, tag type, tag level, data characteristics, and the number of tags present. In one embodiment, after determining the tag population, the interrogator 101 designates a group of tags from the entire tag population to be programmed simultaneously. In some cases, such as when a user manually enters a group of tags, or when a tag list is already stored in the interrogator memory 111, the interrogator 101 skips the initial count.

There are various methods for scanning a population of tags to determine the individual characteristics of the tags. In one embodiment, the RFID tag has one or more sessions (e.g., sessions 0-3). Each session can store a state with two values (e.g., state A and state B). In one embodiment, one of the states can be a persistent state and the other can be a transient state. The interrogator uses a series of coded interrogation signals to search for a population of tags. The search can be a random search or a binary tree search that systematically classifies and separates groups and subgroups that match an increasing number of specific search criteria.

In one embodiment, the interrogator 101 counts the tags using one or more count commands (e.g., query, ACK, and NAK). The query command initiates and specifies a count cycle, and one or more tags respond to it with a 16-bit number. If the interrogator 101 successfully extracts the 16-bit number, it is sent back to the tag for handshaking via the ACK command. If the 16-bit number sent by the ACK command matches the number sent by the tag, the tag responds. The tag that has confirmed its 16-bit number then responds with a prefix, its CRC (cyclic redundancy check), and its EPC (electronic product code). In another embodiment, the number can be in the range of 8 to 64 bits. The tag then switches its internal state for the session from A to B (or from B to A) unless it receives a NAK. If it receives a NAK, it remains in the previous state. The interrogator can discover tags in the tag population and convert the internal states of all discovered tags. In other embodiments, the interrogator 101 uses other count commands, operations, or methods to count the tag population. In one embodiment, a tag has four sessions available, each with a single bit of independent state memory. This session structure allows up to four interrogators or processes to communicate with a tag population in a multitasking environment, however other embodiments may allow more than four interrogators.

Specify individual tags to programmatically

In one embodiment, the inventoried tags are added to the memory of the interrogator and the group of designated tags is selected from the population of inventoried tags. In one embodiment, the inventoried tags are presented in the interrogator 101 as a queue or list of tags.

In one embodiment, the interrogator 101 can designate individual tags to be added to a simultaneous programming group by specifying the tag's serial number or unique tag ID. The tag serial number and unique tag ID can be discovered during the initial inventory phase, or the interrogator 101 can have a pre-set list of tags for programming. In one embodiment, the interrogator 101 can automatically group individual tags for programming based on programming intervals, tag class, data stored in tag memory, or other characteristics. For example, the interrogator 101 can select a group of only Class II tags for programming, or can select a group of tags with serial numbers within a limited range. In other embodiments, a user can manually select a group of tags for simultaneous programming. In one embodiment, a user can designate individual tags to be added to a simultaneous programming group using a tag serial number or unique tag ID.

In one embodiment, a group of Tags designated for simultaneous programming includes two or more Tags. In one embodiment, the interrogator 101 is capable of designating a single group of four hundred or more Tags for simultaneous programming and programming the group simultaneously according to the method described below. In one embodiment, after programming, the Tags are individually verified whether the programming was successful. The successfully programmed Tags are removed from the list or queue of Tags to be programmed and the next group of Tags is designated. The interrogator 101 continues to program the designated group of Tags until no more Tags remain to be programmed. In one embodiment, when there are no more groups of Tags to be programmed, the interrogator 101 provides a completion status message and records the completion of the programming to the interrogator's internal memory.

Different types of tags may require different durations to submit data to the memory. The time required to submit data to the memory can also be mentioned as a programming interval, and can be directly related to the amount of time required for the tag to receive a stable power supply during programming. For example, some tags can submit data to the tag memory with ten microseconds or less under a stable power supply, while other tags may need twenty microseconds or more under a stable power supply in order to submit data to the memory of the tag. The maximum number of tags that the interrogator 101 can program in a group depends on the duration that the interrogator 101 can maintain communication with the tag group and maintain power to the tag group. For example, local wireless frequency regulations may require that the interrogator 101 limit the duration spent communicating with the tag group and powering it. In one embodiment, the interrogator 101 determines the total duration allowed to communicate with the tag group and power supply, and automatically queues a plurality of tags that can be successfully programmed within a given time.

In one embodiment, during the inventory, interrogator 101 stores details about each tag. The interrogator can determine various characteristics of the tags within a population of tags and can group tags by specific characteristics. In one embodiment, interrogator 101 can group tags based on the minimum time required for the tags to submit data to memory. For example, a population of tags may be a mix of tags that require ten microseconds to program and tags that require twenty microseconds to program. In one embodiment, interrogator 101 sets the programming interval to at least twenty microseconds and programs the entire population with a programming interval of at least twenty microseconds. In another embodiment, interrogator 101 groups tags that require ten microseconds of programming intervals together in one or more simultaneous programming groups, separate from groups that require twenty microseconds. In another embodiment, interrogator 101 determines the longest required programming interval from all tags to be programmed and uses this longest required programming interval as the default programming interval for programming all tags. In one embodiment, interrogator 101 uses each tag's programming interval requirement to maximize the number of tags that can be programmed in a group before having to switch frequencies.

Addressing indicator

Tags are manufactured with several states that control how the tag responds to commands. For example, EPC Gen 2 tags contain Ready, Acknowledged, Open, and Secure states (among other states). The tag's logic determines the behavior of the various tag states. For example, Ready and Cancel are two states a tag can enter upon power-up. A tag in the Ready state does not participate in an inventory cycle. The Open and Secure states are used by access commands (commands that read from or write to the tag). The Open state is capable of executing all access commands except Lock and Block Permalock. The Secure state is capable of executing all access commands.

In one embodiment, each tag includes a "being addressed" indicator. In one embodiment, the being addressed indicator is a flag or bit that can be set in the tag's memory. In one embodiment, activating/setting the being addressed indicator is accomplished by changing the tag's being addressed bit from 0 to 1. In other embodiments, the being addressed indicator can be implemented and operated in other ways.

In one embodiment, Tags with activated/set being addressed indicators may remain in the addressable state while Interrogator 101 continues to promote other Tags to the addressable state. Further details of the operation of simultaneous programming commands are discussed below.

Tags that do not have a being addressed indicator or have an inactive indicator can only be addressed one at a time because tags change their state when they receive a command to address a different tag. For example, without a being addressed indicator, a command to address the memory of tag A causes nearby tags B, C, and D to exit their addressable state.

In one embodiment, an open or secure state with an activated/deasserted addressing indicator is capable of receiving and processing simultaneous program commands. In one embodiment, simultaneous program commands include commands to address and prepare data for programming, as well as commands to commit data to the memory. Simultaneous program commands are discussed in more detail further below.

In one embodiment, activating/setting the being-addressed indicator in the open or secure state transitions that state to a separate and independent open-addressed or secure-addressed state. In other embodiments, activating/setting the being-addressed indicator in the open or secure state does not change the existing state, but allows a group of Tags to receive and process simultaneous programming commands. It will be apparent to one skilled in the art that other states may also be modified to include the being-addressed indicator.

In one embodiment, the Tag also includes a Being Addressed independent Tag state that is separate from the states described above and separate from the Being Addressed indicator associated with the Open or Secure states. In one embodiment, the Being Addressed state also allows the Tag to receive and process simultaneous programming commands. In one embodiment, in order to receive and process simultaneous programming commands sent to a group of Tags, the Tag receives a command to switch to the Being Addressed state. In one embodiment, the Tag is placed in the Being Addressed state before the simultaneous programming commands are sent. In one embodiment, a Tag in the Being Addressed state remains in the Being Addressed state until a signal is received to exit the Being Addressed state (e.g., from a query or NAK command).

In one embodiment, unlike the Open or Secure states, the Being Addressed state does not respond to programming commands with a backscattered reply. In one embodiment, while in the Being Addressed state, the Tags receive programming commands and do not reply with any error reports. In one embodiment, to verify successful simultaneous programming, as further described below, the Interrogator 101 issues a separate confirmation verification to each Tag.

In one embodiment, upon power-up, Tags are not permitted to enter the Being Addressed state. In one exemplary embodiment, Tags to be programmed are transitioned to the Being Addressed state during the inventory process. In other embodiments, Tags to be programmed are in the Confirmed state (or other state) after the inventory process and are subsequently transitioned to the Being Addressed, Open Addressed, or Secure Addressed state by Interrogator 101. In one embodiment, Tags that have not transitioned to the Being Addressed, Open Addressed, or Secure Addressed state cannot receive and process simultaneous programming commands.

Programmatically selected tags

In one embodiment, Tags in the Being Addressed, Open Addressed, or Secure Addressed states are capable of receiving simultaneous programming commands. In one embodiment, unique data is simultaneously programmed to a group of Tags using two command operations: 1) a command for addressing a specified Tag and transmitting data to be programmed to the specified Tag, and 2) a command for submitting addressed data for a specified group of Tags. In one embodiment, the same data is simultaneously addressed and programmed to a group of Tags using one command operation rather than two.

In one embodiment, there are three types of simultaneous programming commands. The Batch Program command programs identical/identical data (e.g., the same color and model of a product) to a group of tags. The Program Set and Program Commit commands program unique data to each tag in a specified group of tags (e.g., a unique serial number). It will be apparent to one skilled in the art that whether the data is actually unique is optional when using the Program Set and Program Commit commands. In other embodiments, there may be different command names and types that also provide simultaneous programming commands. In one embodiment, multiple commands can be used with the addressing, open addressing, and secure addressing states (e.g., Write, Block Write, and Lock commands). In one embodiment, the Write command writes data to the tag memory. In one embodiment, the Block Write command writes multiple 16-bit words to the tag memory. In other embodiments, the Block Write word size may be 8 bits, 32 bits, or other lengths. In one embodiment, the Lock command locks a password and prevents subsequent writes using the locked password. The Lock command can also lock individual memory regions to prevent subsequent writes to specific memory regions.

In one embodiment, interrogator 101 uses a predefined exclusive handle to establish an I/O data link to a tag in the being addressed state. For example, the handle can be a 16-bit number consisting of all zeros. This predefined exclusive handle is used to send simultaneous programming commands to the tag. Commands received by the tag from handles other than the exclusive handle are ignored, and the tag will not act on commands not related to simultaneous programming.

In one embodiment, Tags capable of receiving simultaneous programming commands do not require a handle to receive simultaneous programming commands. In one embodiment, Tags in the Being Addressed, Open Addressed, or Secure Addressed states ignore commands sent with a handle that is not an Exclusive Simultaneous Programming handle.

Batch programming unique data

In one embodiment, the method for programming unique data is divided into multiple commands. The Program Setup command establishes individual tag addressing and provides the data to be programmed for each specified tag. The Program Commit command causes the tag to program (commit) the addressed data to the tag memory.

In one embodiment, the programming setup commands individually address and send data to each tag in a group of specified tags. For example, for a group of ten tags, tag 1 will receive a programming setup command addressed to tag 1, tag 2 will receive a programming setup command addressed to tag 2, and so on. The interrogator 101 issues programming setup commands individually for each tag in the specified tag group until each tag has been addressed and the data has been sent to the specified tag address. In one embodiment, the programming setup data sent to each tag in a group can be unique data (e.g., a unique serial number). In one embodiment, the programming setup commands specify a memory area of the tag, and the data is stored in the memory area. In one embodiment, the programming setup commands address each tag based on the tag's serial number or unique tag ID.

In one embodiment, the program setup command causes each individual tag to temporarily store data in one or more flip-flops or latches while power is continuously applied to the tags. In one embodiment, when a programming interval is received, the designated tag fully commits the data to the memory. In one embodiment, to commit the data sent by the program setup command, the interrogator 101 issues a program commit command to maintain power during the programming interval. As discussed above, tags may have different required durations to fully commit data to the tag memory. In one embodiment, to fully program the tag, the interrogator 101 maintains power for at least twenty microseconds. In one embodiment, the interrogator 101 selects the programming interval based on the designated tag type determined during the initial inventory phase. In one embodiment, the programming interval commits the data to the non-volatile memory so that another interrogator can access the data at a future point in time.

Figure 4 illustrates a flow chart representation of one embodiment of a method for individually and simultaneously programming addressing data to each Tag in a group of Tags.At block 405, the interrogator 101 interrogates the population of Tags.

At block 410, the interrogator 101 specifies a group of tags from the entire inventory population. In one embodiment, the interrogator 101 specifies a group of tags from an initial population of tags. In one embodiment, the interrogator 101 successively programs groups of tags until all inventory tags are successfully programmed.

At block 415, Interrogator 101 sets the being addressed indicator for each Tag to be programmed in the designated group of Tags.

At block 420, the interrogator 101 provides the data to be programmed to each designated Tag in the group of designated Tags. In one embodiment, the interrogator 101 provides the data to be programmed to each Tag individually until each designated Tag in the group has received the data to be programmed.

At block 425, Interrogator 101 provides a command to program all of the specified group of Tags simultaneously. In one embodiment, Interrogator 101 maintains a duration specified by a programming interval while the group of Tags programs data to memory.

At block 430 , Interrogator 101 individually verifies that the programming command was successful for each individual Tag in the specified group.

At block 435, the interrogator resets the being addressed indicator for all Tags in the designated group of Tags.

Batch programming of the same data

The batch program command is sent concurrently with the programming interval. In one embodiment, the batch program command includes the destination memory area, the data to be programmed, and the programming interval. Interrogator 101 determines the duration of the programming interval as described above. In one embodiment, the batch program command is received and processed by Tags in the Being Addressed, Open Addressed, or Secure Addressed states. In one embodiment, Tags with the Being Addressed indicator activated/set are able to receive the batch program command.

Figure 5 illustrates a flow chart representation of one embodiment of a method for simultaneously programming a group of designated Tags with the same data.At block 505, the Interrogator 101 takes an inventory of the Tag population.

At block 510, the interrogator 101 specifies a set of tags from an inventory population.

At block 515, Interrogator 101 sets the being addressed indicator for each Tag to be programmed in the designated group of Tags.

At block 520, Interrogator 101 sends a simultaneous program command to the entire group of designated Tags. In one embodiment, the simultaneous program command contains the data to be programmed and maintains power for a designated programming interval.

At block 525, Interrogator 101 individually verifies for each individual Tag in the designated group whether the programming command was successful.

At block 530, the interrogator resets the being addressed indicator for all Tags in the designated group of Tags.

Figure 6 illustrates a flow chart representation of one embodiment of a method for implementing tags participating in simultaneous programming.At block 605, tags participate in an inventory.

At block 610 , the Tag receives a command to set its being addressed indicator and executes internal logic to set the being addressed indicator.

At block 615, the Tag receives one or more simultaneous programming commands as described above.

At block 620, the Tag receives a command to verify the success of the simultaneous programming command and sends back a reply to the verification command.

At block 625 , the Tag receives the command to reset its being addressed indicator and executes internal logic to reset the being addressed indicator.

Verify programming success

A group of tags being programmed simultaneously may respond to the simultaneous programming automatically and simultaneously, such that the responses conflict with each other, making a single response difficult for the interrogator 101 to discern. In one embodiment, the success of the simultaneous programming is verified for each tag. Individual verification of the tags ensures that the interrogator 101 receives a clear response from each tag. In one embodiment, the interrogator 101 verifies the data programmed into the tags by issuing a verification command to each tag individually. The verification command returns a response from the tag indicating whether the programming of the tag was successful. If the tag programming command is unsuccessful or the interrogator 101 does not receive a response, the tag is added back to the queue of tags to be programmed. The interrogator 101 retries the failed or unidentified tags in a subsequent round of simultaneous programming by reissuing the programming command.

Reset the addressing indicator

Based on verification that a Tag has been successfully programmed with the correct data, Interrogator 101 resets the BeingAddressed, OpenAddressed, or SecureAddressed state. In one embodiment, an Query or NAK command is sufficient to reset the BeingAddressed, OpenAddressed, or SecureAddressed state. In one embodiment, after successfully programming a group of Tags, Interrogator 101 switches from the BeingAddressed, OpenAddressed, or SecureAddressed state to another state (e.g., Ready state or Arbitration state). In one embodiment, Interrogator 101 resets, deactivates, or deselects the BeingAddressed indicator based on verification that a Tag has been successfully programmed.

In one embodiment, the interrogator 101 also locks the Tag's memory before resetting or transitioning from the being addressed, open addressed, or secure addressed state. In one embodiment, the interrogator 101 locks the Tag's memory after resetting or transitioning from the being addressed, open addressed, or secure addressed state.

Various embodiments and aspects of the present invention have been described above, and the accompanying drawings illustrate these various embodiments. In the foregoing description, the invention has been described with reference to specific exemplary embodiments thereof. It will be apparent that various modifications may be made without departing from the broader spirit and scope of the invention as set forth in the following claims. The specification and drawings are, therefore, to be regarded in an illustrative rather than a restrictive sense.

Reference to an embodiment in the specification indicates that a particular feature, structure, or characteristic described in connection with the embodiment is included in at least one embodiment of the present invention. In the specification, the appearance of the phrase "in one embodiment" in different places does not necessarily refer to the same embodiment.

The foregoing embodiments of the present invention may be described as a process, which is often depicted as a flow chart, flow diagram, structure diagram, or block diagram. Although a flow chart may describe operations as a sequential process, many of these operations may be rearranged. When the operations of a process are completed, the process is terminated. A process may correspond to a method, procedure, process, and the like.

Claims (44)

1. A device for identifying and programming tags, the device comprising: Transmitter; Receiver; and The microprocessor is configured as follows: Multiple tags are identified by their respective unique tag identifiers to receive the first set of commands and the second set of commands. Transmit a first set of commands to the identified multiple tags, wherein the first set of commands includes a command to set an addressing status indicator in each of the identified multiple tags to receive a second set of commands, and A second set of commands is transmitted to the plurality of tags having addressable status indicators that have been set, wherein the second set of commands includes commands for setting a time interval for receiving power to simultaneously program data for the plurality of tags, wherein the first set of commands is to maintain the addressable state of at least one of the tags while raising one or more other tags to the addressable state, in which data is simultaneously programmed into the plurality of tags. 2. The apparatus of claim 1, wherein the microprocessor is further configured to issue a third set of commands to a plurality of programmed tags, wherein the third set of commands includes a command individually verifying that data has been successfully programmed into the plurality of tags. 3. The apparatus of claim 1, wherein the second set of commands includes commands for establishing an address for each of the specified plurality of tags and for transmitting data to the address of each of the specified plurality of tags. 4. The apparatus of claim 1, wherein the command to set the addressing status indicator allows multiple specified tags to receive the second set of commands simultaneously. 5. The device as claimed in claim 1, which operates in a frequency range of 900 MHz. 6. The apparatus of claim 1, further comprising a network interface. 7. The apparatus of claim 1, wherein the microprocessor is further configured to issue commands for handshaking with the plurality of tags. 8. The apparatus of claim 1, further comprising a near-field loop antenna coupled to at least one of the transmitter or receiver. 9. An apparatus for identifying and programming tags, the apparatus comprising: Transmitter; Receiver; and The processing logic is configured as follows: Multiple tags are identified by their respective unique tag identifiers to receive the first set of commands and programming commands. Transmit a first set of commands to the identified multiple tags, wherein the first set of commands includes a command to set an addressing status indicator in each of the identified multiple tags to receive programming commands. Transmit programming commands to the plurality of tags having addressable status indicators that have been set, wherein the programming commands include data and commands for setting time intervals for the plurality of tags to receive power to program the data simultaneously, wherein a first set of commands is to maintain the addressable status of at least one of the tags while raising one or more other tags to the addressable status, in which data is simultaneously programmed into the plurality of tags. 10. The apparatus of claim 9, wherein the processing logic is further configured to issue a second set of commands to a plurality of programmed tags, wherein the second set of commands includes a single command to verify that data has been successfully programmed into the plurality of tags. 11. The apparatus of claim 9, wherein the processing logic is further configured to determine that the programming command is unsuccessful in the programming tag, and to add the tag of unsuccessful programming to the programming queue. 12. The apparatus of claim 9, wherein the addressing status indicator is to indicate the addressable status of the plurality of tags. 13. The apparatus of claim 12, wherein the addressable state of the plurality of tags allows for simultaneous programming of the plurality of tags. 14. The device of claim 9, wherein it operates in a frequency range of 900 MHz. 15. The apparatus of claim 9, wherein the processing logic is a microcontroller. 16. The apparatus of claim 9, further comprising a dynamic random access memory and a memory controller for controlling the operation of the dynamic random access memory. 17. The apparatus of claim 9, further comprising a directional coupler. 18. The apparatus of claim 9, further comprising a network interface. 19. The apparatus of claim 9, wherein the processing logic is further configured to issue commands for handshaking with the plurality of tags. 20. A label comprising: A receiver that detects one or more signals representing one or more commands; The memory contains an address status indicator and a unique tag identifier; and A processor, coupled to the receiver and the memory, is configured to set an addressing state indicator on the tag when the receiver detects a first signal indicating a first command to address the tag by a unique tag identifier, and wherein the addressing state indicator is to keep the tag in an addressing state when the receiver detects a second signal indicating a second command to address other tags based on different unique tag identifiers. The processor coupled to the receiver is configured to receive a third signal indicating a command to set a time interval for receiving power to program data simultaneously with other tags for tags in the addressing state. 21. The tag of claim 20, wherein the addressing state allows processing of simultaneous programming commands. 22. The tag of claim 20, wherein the simultaneous programming command uses an exclusive handle. 23. The tag of claim 20, further comprising an antenna coupled to the receiver for receiving radio frequency signals from the reader. 24. The tag of claim 20, wherein the tag is a single integrated circuit. 25. The tag of claim 20, wherein the simultaneous programming command is addressed to the tag based on a unique tag identifier, and wherein the unique tag identifier includes at least one of a unique serial number or a unique tag identification number. 26. A machine-implemented method, comprising: Multiple tags are identified by their respective unique tag identifiers to receive the first set of commands and the second set of commands. Transmit a first set of commands to a plurality of identified tags, wherein the first set of commands includes a command to set an addressing status indicator in each of the plurality of identified tags to receive a second set of commands; and A second set of commands is transmitted to the plurality of tags having addressable status indicators that have been set, wherein the second set of commands includes commands for setting a time interval for receiving power to simultaneously program data into the plurality of addressed tags, wherein the first set of commands is to maintain the addressable state of at least one of the tags while raising one or more other tags to the addressable state, in which data is simultaneously programmed into the plurality of tags. 27. The machine-implemented method of claim 26, further comprising: A third set of commands is transmitted to the multiple tags being programmed, wherein the third set of commands includes a single command to verify that data has been successfully programmed into the memory of the prepared tag. 28. The machine-implemented method of claim 26, wherein setting the addressing state indicator is to activate the addressing state of the tag. 29. The machine-implemented method of claim 28, further comprising: It was confirmed that the data was successfully programmed into the tag's memory; and Issue a command to reset the addressing status indicator for that label. 30. A machine-implemented method, comprising: Multiple tags are identified by their respective unique tag identifiers to receive the first set of commands and programming commands; Transmit a first set of commands to a plurality of identified tags, wherein the first set of commands includes a command to set an addressing status indicator in each of the plurality of identified tags to receive programming commands; and Transmit programming commands to the plurality of tags having addressable status indicators that have been set, wherein the programming commands include data and commands for setting time intervals for receiving power to simultaneously program data for the plurality of tags, wherein a first set of commands is to maintain the addressable state of at least one of the tags while raising one or more other tags to the addressable state, in which data is simultaneously programmed into the plurality of tags. 31. The machine-implemented method of claim 30, further comprising: A second set of commands is transmitted to the multiple tags being programmed, wherein the second set of commands includes a single command to verify that data has been successfully programmed into the memory of the prepared tag. 32. The machine-implemented method of claim 30, wherein the addressing status indicator of the tags is to indicate the addressing status of the plurality of tags. 33. The machine-implemented method of claim 32, further comprising: It was confirmed that the data was successfully programmed into the tag's memory; and Issue a command to reset the addressing status indicator for that label. 34. A method for execution in a tag having a unique tag identifier, the method comprising: In response to a first command addressing a tag including a unique tag identifier, an addressing status indicator is set on the tag, wherein the addressing status indicator is intended to keep the tag in an addressing state if the tag receives a second command addressing another tag including a different unique tag identifier; and Receive commands for setting the time interval for a tag in the addressing state to receive power so that it can program data simultaneously with other tags. 35. The method of claim 34, wherein setting the addressing status indicator allows processing of simultaneous programming commands. 36. A data processing system, comprising: A means for identifying multiple tags by corresponding unique tag identifiers to receive a first set of commands and a second set of commands; A means for transmitting a first set of commands to a plurality of identified tags, wherein the first set of commands includes a command to set an addressing status indicator in each of the plurality of identified tags to receive a second set of commands; and A means for transmitting a second set of commands to a plurality of tags having addressable status indicators that have been set, wherein the second set of commands includes commands for setting a time interval for receiving power to simultaneously program data for the plurality of tags, wherein the first set of commands is to maintain the addressable state of at least one of the tags while raising one or more other tags to the addressable state, in which data is simultaneously programmed into the plurality of tags. 37. The data processing system of claim 36, further comprising: A means for issuing a third set of commands to a plurality of programmed tags, wherein the third set of commands includes commands individually verifying that data has been successfully programmed into each of the plurality of tags. 38. The data processing system of claim 36, further comprising: A device for setting the addressing status indicator of a tag. 39. The data processing system of claim 36, further comprising: A device for determining whether the programming of data onto a label is successful; and A means for issuing commands to reset the addressing status indicator of the tag. 40. A data processing system, comprising: A means for identifying multiple tags by corresponding unique tag identifiers to receive a first set of commands and programming commands; A means for transmitting a first set of commands to a plurality of identified tags, wherein the first set of commands includes commands for setting an addressing status indicator in each of the plurality of identified tags to receive programming commands; and A means for transmitting programming commands to a plurality of tags having addressable state indicators that have been set, wherein the programming commands include data and commands for setting a time interval for the plurality of tags to receive power to simultaneously program the data into memory, wherein a first set of commands is to maintain at least one of the tags in an addressable state while raising one or more other tags to an addressable state in which data is simultaneously programmed into the plurality of tags. 41. A data processing system, comprising: Means for setting an addressing status indicator on a tag in response to a first command addressing a tag including a unique tag identifier, wherein the addressing status indicator is to keep the tag in an addressing state if the tag receives a second command addressing another tag including a different unique tag identifier; and A means for receiving a command for setting a time interval for a tag in an addressing state to receive power so as to program data simultaneously with other tags. 42. The data processing system of claim 41, further comprising: A device for verifying data programmed onto a tag. 43. The data processing system of claim 41, wherein the second command includes a command to activate the addressing state of other tags. 44. The data processing system of claim 43, further comprising: A device for determining whether the programming of data onto a label is successful; and A means for issuing commands to reset the addressing status indicator of the tag.