Abstract:
Embodiments of a radio frequency identification tag are generally described herein. Other embodiments may be described and claimed.

Description:
FIELD 
   Embodiments of the present invention may relate to radio frequency devices and/or radio frequency identification (RFID) tags. 
   BACKGROUND 
   Goods and other items may be tracked and identified using a radio frequency identification (RFID) system/device. The RFID system may include an RFID tag that is placed on the item (such as a product) to be tracked. The RFID tag may be a small transponder that can be read by an RFID reader (or interrogator). The RFID reader may include a transceiver and an antenna. The antenna may emit electromagnetic (EM) waves generated by the transceiver, which, when received by the RFID tag, activates the RFID tag. Once the RFID tag has been activated, the RFID tag may modify and reflect the waves back to the RFID reader, thereby identifying the item to which the RFID tag is attached or is otherwise associated with. 
   The RFID reader may be a hand held or stationary device that transmits a radio signal that may be intercepted by the RFID tag. When the RFID tag passes through the radio waves, the RFID tag detects the signal and is activated. Data encoded in the RFID tag may then be transmitted to the RFID reader for further processing. This type of system allows for quick and easy identification for a large number of items by simply passing them through the scope of an RFID reader. This type of system may also identify items on which the RFID tag is not exposed, such as items in which the tag is located internally. Further, the RFID reader may read multiple tags very quickly, such as items passing by the RFID reader while the items are on a conveyer belt, for example. 
   There are at least three basic types of RFID tags, namely a beam-powered RFID tag, a battery-powered RFID tag and an active RFID tag. The beam-powered RFID tag is a passive device that receives energy required for operation from the radio waves generated by the RFID reader. The beam-powered tag rectifies an EM field and creates a change in reflectivity of the field that is reflected to and read by the RFID reader. The battery-powered RFID tag may receive and reflect EM waves from the RFID reader. However, the battery-powered RFID tag may include a battery to power the RFID tag. Additionally, the active tag may actively transmit EM waves that are then received by the RFID reader. 

   
     BRIEF DESCRIPTION OF THE DRAWINGS 
     The foregoing and a better understanding of embodiments of the present invention may become apparent from the following detailed description of arrangements and example embodiments and the claims when read in connection with the accompanying drawings, all forming a part of the disclosure of this invention. While the foregoing and following written and illustrated disclosure focuses on disclosing arrangements and example embodiments of the invention, it should be clearly understood that the same is by way of illustration and example only and the invention is not limited thereto. 
     The following represents brief descriptions of the drawings in which like reference numerals represent like elements and wherein: 
       FIG. 1  shows an RFID system according to an example arrangement; 
       FIG. 2  shows an RFID system according to an example embodiment of the present invention; 
       FIG. 3  shows an RFID tag for use in an RFID system according to an example embodiment of the present invention; 
       FIG. 4  shows a product having an RFID tag according to an example embodiment of the present invention; 
       FIG. 5  is a flowchart showing operations of an RFID system according to an example embodiment of the present invention; and 
       FIG. 6  is a block diagram of a system according to an example embodiment of the present invention. 
   

   DETAILED DESCRIPTION 
   In the following detailed description, like reference numerals and characters may be used to designate identical, corresponding or similar components in differing figure drawings. Further, in the detailed description to follow, example sizes/models/values/ranges may be given although the present invention is not limited to the same. Where specific details are set forth in order to describe example embodiments of the invention, it should be apparent to one skilled in the art that the invention can be practiced without these specific details. 
     FIG. 1  shows an RFID system according to an example arrangement. Other arrangements are also possible. More specifically,  FIG. 1  shows an RFID system  10  that includes an RFID reader  20  and an RFID tag  50 . While not shown, the RFID system  10  may also include a number of other RFID tags, which may be similar or different than the RFID tag  50 . The RFID reader  20  may transmit information via a wireless air interface  40  to the RFID tag  50 . The air interface  40  enables the RFID reader  20  to provide power, query data and/or timing information to the RFID tag  50  so that the RFID tag  50  may provide response data. Specifically, the RFID tag  50  may scavenge power from a received radio-frequency (RF) signal, and may backscatter the response data to the RFID reader  20  by modulating an impedance of an associated antenna. For example, in a half-duplex communications arrangement, the RFID reader  20  may modulate an RF waveform with information (e.g., bits). During a tag-to-reader transmission, the RFID reader  20  may transmit a Continuous-Wave (CW) radio signal. The RFID tag  50  may then backscatter-modulate the CW signal with bits to create a radio-frequency (RF) information waveform that is transmitted back to the RFID reader  20 . 
   The RFID reader  20  may include a memory  22  to store various algorithms and information, a core  24  (e.g., a controller or processor) to control operations of the RFID reader  20 , and a front end  26 , which is operatively coupled to an antenna  28 , to control the transmission of information via the air interface  40  and also to process backscatter information received via the air interface  40  by the antenna  28 . 
   The RFID reader  20  may be coupled (e.g., via a network  30 ) to a further processing system, such as a server  32 . This may allow for programming and/or control of the RFID reader  20  by the server  32 . Further, the RFID reader  20  may provide data, via the network  30 , to the server  32  for a variety of purposes. For example, multiple RFID readers  20  may be coupled to a processing system, such as the server  32 , so as to provide the server  32  with a comprehensive view of a particular environment. That is, multiple RFID readers  20  may be deployed at various locations within a warehouse. Each of the RFID readers  20  may be coupled via the network  30  (e.g., a wired and/or wireless network) to one of more servers  32 , so as to provide a warehouse operator with RFID access to multiple locations within the warehouse, and/or across multiple warehouses. 
   The RFID tag  50  may include an RFID circuit  60  (e.g., an RFID Integrated Circuit (IC)), and an antenna  80  to facilitate reception and transmission of radio-frequency signals via the air interface  40 . The RFID circuit  60  and the antenna  80  may be located on a base material or substrate (e.g., a plastic or paper material) to thereby constitute the RFID tag  50 . The RFID tag  50  may include a number of subcomponents, any one or more of which may be implemented on one or more integrated circuits that form part of the RFID tag  50 . 
   More specifically,  FIG. 1  shows that the RFID circuit  60  includes a power conversion circuit  62 , a transmit/receive circuit  64 , and a memory  66 . As described in detail below, the RFID circuit  60  may also include a power source  68 . The RFID circuit  60  includes components to facilitate the processing of RF signals received via the antenna  80  and also to facilitate the transmission of an RF signal (e.g., a modulated backscatter signal) via the antenna  80 . The memory  66  may store a tag identifier, a product identifier, configuration values applicable to configuration of the RFID tag  50 , one or more algorithms, and/or other suitable information. As noted above, the RFID tag  50  may be a “passive” tag that scavenges power from an RF signal received via the air interface  40 . Alternatively, the RFID tag  50  may be an “active” tag and include the power source  68  to power the RFID tag  50 . 
   The air interface  40  may facilitate both full and half duplex communications, for example. Further, while arrangements and embodiments are described herein as utilizing RF signals to communicate, other forms of wireless communication across the air interface  40  may be utilized. For example, in various embodiments, coupling between the RFID reader  20  and the RFID tag  50  may be achieved utilizing inductive coupling, close coupling, or electrical coupling. 
   Embodiments of the present invention may include an RFID tag that includes at least an antenna, an auxiliary interface device and a dual-ported non-volatile memory device. The antenna may send and receive data across a wireless interface. The auxiliary interface device may couple with an apparatus external to the RFID tag, such as a server or computer. Additionally, the non-volatile memory device may include at least a first port associated with the antenna and a second port associated with the auxiliary interface device, such as input/output (I/O) pins. The auxiliary interface device may include a communication link to communicate data information to and from the memory device and a power link to provide power to the RFID tag. The RFID tag may communicate data over a wireless interface using the antenna or a wired interface through the auxiliary interface device. 
     FIG. 2  shows an RFID system according to an example embodiment of the present invention. Other embodiments and configurations are also within the scope of the present invention. More specifically,  FIG. 2  shows an RFID tag  100  and a server component  200  that are coupled together by a wired interface  250  (such as a bus interface). In this context, the wired interface relates to a physical connection between two entities, such as by wires, cables, a bus, etc. Both the RFID tag  100  and the server component  200  may be provided together within one server chassis, for example. Alternatively, the server component  200  may be a server chassis and the RFID tag  100  may be coupled to the server component  200  either within the chassis or external to the chassis. Although not specifically shown in  FIG. 2 , a RFID reader (such as the RFID reader  20  in  FIG. 1 ) may also be considered as part of the RFID system. Such an RFID reader may send and receive signals via an air interface with an antenna  110  of the RFID tag  100 . As one example, the antenna  110  may be coupled to allow communication with an RFID reader located external to a server chassis. 
   The RFID tag  100  may include the antenna  110 , a power conversion circuit  120 , a transmit/receive circuit  130 , a memory device  140  and an auxiliary interface device  150 . The RFID tag  100  may also include a power supply adaptor  160  that is coupled to the auxiliary interface device  150  so as to obtain power for the RFID tag  100  when the RFID tag  100  is physically coupled to the server component  200  via the wired interface  250 . Other components and circuits may be provided on the RFID tag  100  but are not discussed herein for ease of illustration and discussion. The antenna  110 , the power conversion circuit  120 , the transmit/receive circuit  130 , the memory device  140 , the auxiliary interface device  150  and the power supply adaptor  160  may be provided on an RFID IC. While  FIG. 2  separately shows power conversion circuit  120  and power supply adaptor  160 , both features may be provided as one component. The same may also apply to other features in the figures. 
   As shown, the memory device  140  may be a dual-ported memory device that includes a non-volatile memory  142  and a dual-ported multiplexer  145  (or memory controller). As one example, the memory  142  may be a random access memory (RAM). Thus, the memory device  140  may be referred to as a dual-port non-volatile random access memory device and/or a dual-port non-volatile random access memory. Although the above example describes a particular type of memory device, the methods and apparatus described herein may use other suitable memory devices. 
   The power conversion circuit  120  may receive a signal from the antenna  110  and convert the signal into electric energy. The electric energy may be used to power the non-volatile memory  142 , for example, when needed. Stated differently, the power conversion circuit  120  may create direct current (DC) power from an external radio frequency signal. The transmit/receive circuit  130  may control operations of the RFID tag  100 . For example, the transmit/receive circuit  130  may receive signals from the antenna  110  and perform a conversion (e.g., analog to digital) of the signals. These signals may be provided on a link  135  to access data in the memory device  140  (i.e., in the memory  142 ). 
   The memory device  140  may include at least two ports and thus may be considered a dual-port non-volatile memory device. Other numbers of ports greater than one may also be provided as part of the memory device  140 . Thus, the memory device  140  may include the dual-ported multiplexer  145  (or memory controller) that receives signals along the link  135  (from the transmit/receive circuit  130 ) and along a link  155  (from the auxiliary interface device  150 ). The dual-ported multiplexer  145  applies received signals to the memory  142  so as to access data. Likewise, the dual-ported multiplexer  145  may receive signals from the memory  142  and apply those signals along either the link  135  (to the transmit/receive circuit  130 ) or the link  155  (to the auxiliary interface device  150 ). A first port  141  of the memory device  140  may be used for accessing, sending and/or receiving data to/from the antenna  110 . Thus, the first port  141  of the memory device  140  may be associated with the antenna  110  for transmission/reception via the air interface. A second port  143  of the memory device  140  may be used for accessing, sending and/or receiving data to/from the server component  200  via the wired interface  250 . Thus, the second port  143  of the memory device  140  may be associated with the auxiliary interface device  150  for transmission/reception via the wired interface  250 . 
   The auxiliary interface device  150  may include and/or be coupled to a communication link  155  to send/receive data to/from the second port of the memory device  140 . The auxiliary interface device  150  may also include and/or be coupled to a power source link  157  to supply power to the power supply adaptor  160 , which may in turn supply power to components of the RFID tag  100 . The auxiliary interface device  150  therefore allows communication data to be communicated through the wired interface  250  in addition to data be communicated through the antenna  110  via the air interface. Additionally, the auxiliary interface device  150  allows the RFID tag  100  to be powered by the server component  200  (or other device coupled via the wired interface  250 ) in addition to receiving power over the air interface based on the signal received by the antenna  110 . 
   In at least one embodiment, the server component  200  may be coupled via the wired interface  250  with the RFID tag  100  to provide communication signals and/or power signals. The server component  200  may include an interface/adaptor device  210  to couple the wired interface  250  with a bus  220  such as a system management bus (SMBUS) of the server component  200 . Other circuits/devices  230  of the server component  200  are not discussed herein for ease of discussion. The wired interface  250  and the associated interface devices  150  and  210  may be any of a number of different configurations such as wires, cables, buses, etc. so as to communicate when properly attached and/or coupled to both the RFID tag  100  and the server component  200  (or other device or computer system). For example, the interface devices  150  and  210  and the wired interface  250  may be associated with I 2 C (Inter-IC) Bus, Serial Peripheral Interface (SPI), iWire, Memory Bus, etc. 
   The RFID tag  100  may be provided on or within a server chassis. That is, the onboard RFID tag  100  may be embedded at a board level within the server chassis and have antenna connectivity to outside the server chassis. The RFID tag  100  in such a configuration may provide specific information such as a server name, power up information (relating to sub-nets), etc. 
   The server (including the server component  200 ) may be coupled to a network interface adaptor  270 , which in turn may be coupled to a network  300  such as a local area network (LAN), metropolitan area network (MAN), and/or a wide area network (WAN), for example. Other types of wired and/or wireless networks may also be provided as the network  300 . 
   The wired interface  250  between the server component  200  and the RFID tag  100  allows the server component  200  to read from the memory device  140  when the RFID tag  100  is in a passive mode (and/or an active mode). That is, the server component  200  (located external to the RFID tag  100 ) may read data from the memory device  140  and across the auxiliary memory device  150  when the RFID tag  100  is in a passive mode or an active mode. Additionally, the wired interface  250  between the server component  200  and the RFID tag  100  also allows the server component  200  to write data to the memory device  140  when the RFID tag  100  is in a passive mode (and/or an active mode). That is, the memory device  140  may store (or write) data received from the auxiliary interface device  150  when the RFID tag  100  is in a passive mode. 
     FIG. 3  shows an RFID tag for use in an RFID system according to an example embodiment of the present invention. Other embodiments and configurations are also within the scope of the present invention. More specifically,  FIG. 3  shows an RFID tag  100 ′. Although not specifically shown in  FIG. 3 , the RFID tag  100 ′ may be coupled to other components such as the server component  200  shown in  FIG. 2  along the wired interface  250 . The RFID tag  100 ′ includes several similar components as in the RFID tag  100  shown in  FIG. 2 , and therefore these components will not be discussed again in detail. 
   The RFID tag  100 ′ may include a set of input/output (I/O) pins  170  as the auxiliary interface device. The I/O pins  170  may be coupled by a communication link  175  to a memory interface  180 . The memory interface  180  may be coupled to the memory device  140  by a communication link  185  so as to access locations within the memory  142 . The memory interface  180  (and the link  185 ) may also be considered as part of the memory device  140 . The memory interface  180  may generate signals (such as address signals, data signal, row and column address strobes, etc.) in order to access the specific locations within the memory  142 . 
   Additionally, the power supply adaptor  160  may be a combination of diodes that have output sides connected so as to provide current isolation, such that power sources can operate independently or simultaneously. The power source link  157  may therefore receive a positive voltage (i.e., +V) from the I/O pins  170  and from the power conversion circuit  120 , both being energized from a device/apparatus located external to the RFID tag  100 ′. While  FIG. 3  separately shows power conversion circuit  120  and power supply adaptor  160 , both features may be provided as one component. The same may also apply to other features in the figures. 
     FIG. 4  shows a product having an RFID tag according to an example embodiment of the present invention. More specifically,  FIG. 4  show a product  400  that includes an RFID tag  410  and a product component  430  coupled by a wired interface  420 . The product  400  may be any of numerous types of products, items, objects, etc. such as a server, a laptop computer, etc. The product  400  includes various components that allow the product to work such as various circuits, memories, processors, etc. As one example,  FIG. 4  shows a processor  435  provided within the product component  430  such as a server component or computer component. In  FIG. 4 , the RFID tag  410  may be provided on or within the product  400  and be coupled to the product component  430  so as to allow communication between the RFID tag  410  and the product component  430 . The RFID tag  410  may correspond with the RFID tag  100  shown in  FIG. 2  and/or the RFID tag  100 ′ shown in  FIG. 3 . The communication is enabled based on the wired interface  420  (or bus interface). The wired interface  420  may correspond with the wired interface  250  shown in  FIG. 2 . In a similar manner as discussed above, the product component  430  may also be coupled to a network and/or system so as to provide communication of information to the network and/or system. Likewise as discussed above, an antenna  415  of the RFID tag  410  may also communicate with an RFID reader (not shown in  FIG. 4 ) via an air interface. 
     FIG. 5  is a flowchart showing operations of an RFID system according to an example embodiment of the present invention. Other operations, orders of operations, flowcharts and embodiments are also within the scope of the present invention. More specifically,  FIG. 5  shows that data may be communicated between an RFID tag (i.e., an RFID memory) and an RFID reader via an air interface in block  502 . The RFID tag may be coupled to a specific product (such as server or computer system) in block  504 . Power may be provided from the specific product via a wired interface in block  506 . Additionally, data may be communicated between the RFID tag (i.e., the RFID memory) and the specific product via the wired interface in block  508 . In block  510 , the data received at the specific product in block  508  may be communicated to a network/system for any of various reasons such a location determination, security, inventory, etc. 
     FIG. 6  is a block diagram of a system (such as a computer system  600 ) according to an example embodiment of the present invention. Other embodiments and configurations are also within the scope of the present invention. More specifically, the computer system  600  may include a processor  610  that may have many sub-blocks such as an arithmetic logic unit (ALU)  612  and an on-die (or internal) cache  614 . The processor  610  may also communicate to other levels of cache, such as external cache  620 . Higher memory hierarchy levels such as a system memory (or random access memory RAM)  630  may be accessed via a host bus  640  and a chip set  650 . The system memory  630  may also be accessed in other ways, such as directly from the processor  610  and/or without passing through the host bus  640  and/or the chip set  650 . The system  600  may further include flash memory  655  and/or a peripheral interface to receive the flash memory  655 . The flash memory  655  (and/or peripheral interface) may be coupled to the chipset  650 . In addition, other functional units such as a graphical interface  670  and a network interface  660 , to name just a few, may communicate with the processor  610  via appropriate busses or ports. The processor  610  may be powered by an external power supply  680 . The system may also include a wireless interface  690  coupled to the chipset  650  (or to the processor  610 ) to interface the system  600  with other systems, networks, and/or devices via a wireless connection. Additionally, the system  600  may also include a wired interface  695 . The wired interface  695  may be for communication with the RFID tag  700 . 
   Additionally, an RFID tag  700  may be coupled to the processor  610  by a wired interface  710 . The RFID tag  700  may correspond to the RFID tag  100  shown in  FIG. 2 , the RFID tag  100 ′ shown in  FIG. 3  and/or the RFID tag  410  shown in  FIG. 4 . The wired interface  710  may correspond to the wired interface  250  shown in  FIG. 2  and/or the wired interface  420  shown in  FIG. 4 . Accordingly, the RFID tag  700  may be attached or plugged into the computer system  700  for various reasons such as location determination, security, inventory, etc. 
   Embodiments of the present invention may provide power-on and power-off RFID tag access. For example, embodiments of the present invention may provide power-on and power-off server location determination (or other component location determination). Additionally, various information may be updated on the RFID tag by using an auxiliary interface device and/or I/O pins. This allows the information stored on the RFID tag to be kept current and up-to-date. Additional security information may also be added to the RFID tag using the auxiliary interface device and/or the I/O pins. 
   Embodiments of the present invention may be applicable in numerous environments as will be discussed below merely as examples. Other embodiments, environments and applications are also within the scope of the present invention. Embodiments of the present invention may be provided within or as part of shipping containers. That is, a battery powered product may monitor conditions of the container. The RFID reader that reads the presence of the container may simultaneously (or substantially simultaneously) read out environmental history (e.g. temperature, shock, humidity, time of events, etc.) as well as other information stored at the origin of the shipping. Embodiments of the present invention may also be applicable to sensor network motes such as low or ultra low power sensors that make measurements and store the measured data with a periodicity in the RFID tag&#39;s non-volatile memory. The data may eventually be read and the memory may be cleared at that point. 
   Still further, embodiments of the present invention may also be applicable for security/authentication for wireless Universal Serial Bus (USB) applications. For example, embodiments of the present invention may include an RFID tag integrated into a peripheral to enable enhanced security. Key exchange and rotating authenticity codes may also enhance security. 
   Embodiments of the present invention may also be applicable to laptop wireless fidelity (WiFi) applications. More specifically, an RFID tag in a laptop in a briefcase may be powered down and carried through a security portal. The security portal may read both an employee&#39;s badge number and the laptop&#39;s RFID tag. The system may compare the RFID tag&#39;s serial number to its active computer database and if it is enabled, then write a Wired Equivalent Privacy (WEP) decryption key to the tag&#39;s non-volatile memory. Thus, the next time the laptop is turned on, the laptop may have access to specific sites based on the portals in which the tag has passed. 
   Systems represented by the various foregoing figures can be of any type. Examples of represented systems include computers (e.g., desktops, laptops, handhelds, servers, tablets, web appliances, routers, etc.), wireless communications devices (e.g., cellular phones, cordless phones, pagers, personal digital assistants, etc.), computer-related peripherals (e.g., printers, scanners, monitors, etc.), entertainment devices (e.g., televisions, radios, stereos, tape and compact disc players, video cassette recorders, camcorders, digital cameras, MP3 (Motion Picture Experts Group, Audio Layer 3) players, video games, watches, etc.), and the like. 
   Any reference in this specification to “one embodiment,” “an embodiment,” “example embodiment,” etc., means that a particular feature, structure, or characteristic described in connection with the embodiment is included in at least one embodiment of the invention. The appearances of such phrases in various places in the specification are not necessarily all referring to the same embodiment. Further, when a particular feature, structure, or characteristic is described in connection with any embodiment, it is submitted that it is within the purview of one skilled in the art to affect such feature, structure, or characteristic in connection with other ones of the embodiments. Furthermore, for ease of understanding, certain method operations may have been delineated as separate operations; however, these separately delineated operations should not be construed as necessarily order dependent in their performance. That is, some operations may be able to be performed in an alternative ordering, simultaneously, etc. 
   Although embodiments of the present invention have been described with reference to a number of illustrative embodiments thereof, it should be understood that numerous other modifications and embodiments can be devised by those skilled in the art that will fall within the spirit and scope of the principles of this invention. More particularly, reasonable variations and modifications are possible in the component parts and/or arrangements of the subject combination arrangement within the scope of the foregoing disclosure, the drawings and the appended claims without departing from the spirit of the invention. In addition to variations and modifications in the component parts and/or arrangements, alternative uses will also be apparent to those skilled in the art.