Patent Application
20070013603
1. Field
The present invention relates to circuits and processes for communicating with targets. More particularly, the invention relates to circuits and processes that enable an RF communication path to an IC associated with a target In one example, the RF-enabled target is an RF-enabled optical disc. The present invention also relates to antenna circuits and processes for wireless communication with targets.
2. Description of Related Art
Effective wireless communication with an article coupled to an RFID tag depends on interdependent variables, including the design and location of the antenna, transmitter/receiver (“transceiver”) and the integrated circuit (“IC”) that collectively comprise the tag; the placement and orientation of the tag with respect to the article and the reader; and the design and composition of the article. To maximize signal reception, for example, it is desirable for the antenna to be oriented in a geometric plane perpendicular to that of the RF signal transmitted by the reader. Further, it is desirable for the antenna to be positioned relative to the article such that the article does not interfere with the signal path between the article and an external reader.
Optical discs (e.g. CD's, DVD's etc.) present a particularly complex challenge for RFID tag communication when such discs are stacked in packages for shipment or on retail shelving. Because of their required geometries, RFID antennas are typically located in the same plane as the disc. An optical disc however is comprised of reflective layers of thin metal that span most of the plane of the disc and act as reflectors and attenuators of RF energy transmitted and received by readers. A standard shipping carton containing 30 movies each for example can have as many as 120 layers of metal (2 discs per case, dual layer discs) and 30 RFID tags.
Improved devices and systems for allowing communication between a device with data processing capabilities and a reader are provided to solve the foregoing problems associated with RFID tags and other devices capable of RF communication.
Briefly, the present invention provides devices and methods for providing wireless communication with a target, such as an optical disc or an electronic device. The devices include an integrated processor and an antenna that are connected to the target, which enable a wireless communication with an associated reader or scanning system. The integrated circuit may be embedded in the target, attached to the surface of the target, or in a label attached to the target. In a similar manner, the antenna may be embedded in the target, attached to the surface of the target, or in a label attached to the target Interconnection lines may be used connect the integrated processor to the antenna, and may include a feedthrough arrangement for passing electrical signals between the surface and the interior of the target. A demodulator may also be positioned adjacent or on the antenna, allowing a long lead line to pass demodulated data to the integrated circuit. In one example, the antenna is positioned in or on a case that holds the target, with lead lines connecting the antenna to the target's integrated circuit. One, two, or three antennas may be used, with the multi-antenna arrangements preferably arranging the antennas orthogonally.
In one example, an integrated circuit is embedded in an optical disc, and couples to an antenna. The optical disc may be, for example, a DVD, CD, DVD-9, Blu-ray disc, HD-DVD, or game disc. The disc may also be a pressed or prerecorded media, or may be writeable or rewritable media. The antenna may also be embedded, or may be on the surface of the disc, in a label attached to the disc, or spaced apart from the disc. For an antenna external to the disc, conductive feed-throughs are used to pass signals from the surface of the disc to the embedded processor. The feed-throughs may directly connect to the antenna, or a lead line may be used to allow the antenna to be more flexibly positioned. For example, the antenna may be located in or on the case holding the optical disc. For longer lead lines, a demodulator may be used adjacent the antenna, which allows demodulated data to pass to the integrated circuit. In a specific example, the wireless communication is an RF communication at an RFID or near field communication frequency.
In another example, an antenna is embedded in an optical disc, and couples to an integrated circuit. The optical disc may be, for example, a DVD, CD, DVD-9, Blu-ray disc, HD-DVD, or game disc. The disc may also be a pressed or prerecorded media, or may be writeable or rewritable media. The integrated circuit may also be embedded, or may be on the surface of the disc, in a label attached to the disc, or spaced apart from the disc. For an integrated circuit external to the disc, conductive feed-throughs are used to pass signals from the surface of the disc to the embedded antenna. The feed-throughs may directly connect to the integrated circuit, or a lead line may be used to allow the integrated circuit to be more flexibly positioned. For example, the integrated circuit may be located in the clamping area of the optical disc. In a specific example, the wireless communication is an RF communication at an RFID or near field communication frequency.
A target, such as an optical disc, which has an associated integrated circuit, may be placed in a holding case. An antenna may be placed in or on the case, and coupled to the integrated circuits using lead lines. The case has contacts that enable the antenna to connect to the integrated circuit when the case is closed. The antenna may be in or on the spine of the case, an edge of the case, or the front or back cover to the case. In another arrangement, a second antenna may be positioned in or on the case, and is preferably orthogonal to the first antenna when the case is closed. In another arrangement, a third antenna may be positioned in or on the case, and is preferably orthogonal to both the first and second antenna when the case is closed. In a specific example, the wireless communication is an RF communication at an RFID or near field communication frequency.
Advantageously, the integrated circuit and its antenna system may be flexibly arranged to meet communication specifications for diverse applications, and also may be adapted to meet manufacturing and distribution requirements. In this way, the integrated circuit and its antenna system enabled robust wireless communications between a scanning system and an optical disc, and may be adapted according to specific application needs.
These and other features, aspects and advantages of the present invention will become better understood with regard to the following description, appended claims, and accompanying figures where:
All dimensions specified in this disclosure are by way of example only and are not intended to be limiting. Further, the proportions shown in these Figures are not necessarily to scale. As will be understood by those with skill in the art with reference to this disclosure, the actual dimensions of any device or part of a device disclosed in this disclosure will be determined by their intended use.
Detailed descriptions of examples of the invention are provided herein. It is to be understood, however, that the present invention may be exemplified in various forms. Therefore, the specific details disclosed herein are not to be interpreted as limiting, but rather as a representative basis for teaching one skilled in the art how to employ the present invention in virtually any detailed system, structure, or manner.
It is desirable in some instances for an IC associated with an RFID tag to be embedded in a target so that it can not be readily accessed or removed by would-be thieves. To maintain effective communication with a reader however, it is often desirable to place the antenna external to the target and communicatively couple it to an IC embedded within the target. These desirable conditions are often in conflict with each other and often necessitate that product designers make tradeoffs that significantly affect the performance of the system or increase design and product costs.
Reader arrangements 10 are shown in
Definitions
As used herein, the following terms and variations thereof have the meanings given below, unless a different meaning is clearly intended by the context in which such term is used.
“Activate” refers to the enabling of a target to provide a feature, in particular a functional or other beneficial feature, or to allowing access to such a feature, by an IC. Activation can also refer to a change to a target that is instructed or made by the IC, in particular a change which gives the target a utility that it didn't have prior to activation. For example, activation of a target can comprise allowing a user access to content stored in the target, such as information stored on an optical disc. “Deactivate” refers to rendering a feature of a target inoperative, so that the feature cannot be used or accessed, and/or to returning a target to the state or condition it was in prior to activation. Both activation and deactivation are generally reversible. In addition, the signals and/or codes instructing an IC to activate or deactivate a target are preferably communicated in a secure manner in order to control such activation or deactivation, so that only conditional access to a controlled feature of a target is allowed.
“Authenticated event” or “AE” refers to an action performed by an IC in response to a command issued to the IC in a secure manner, such as through the use of a password system, PKI, or the methods described above. Authenticated events can be, for example, the activation or deactivation of a feature of a target, the permanent disablement of the ability of an IC to activate or deactivate such feature, or the verification of the identity of the target.
“Conditional access” refers to access to a target or to a feature of a target, in particular an attribute which confers utility or value, under the control of a device with data processing capabilities such as an IC. The processor allows or denies access to such feature by activating, deactivating, or otherwise affecting the target or a feature thereof. Such access is preferably provided in a secure manner.
“Conditional access network” refers to a system comprising, at a minimum, a NOC, reader, IC, and target. The components of a conditional access network operate together to provide secure communication between a reader and an IC, and in particular to provide conditional access to an IC and/or to the target (or a feature thereof) with which the IC is in communication. The systems and devices disclosed herein can be used together with a conditional access network.
“Disable,” with regard to RFA ICs, refers to rendering a RFA IC permanently incapable of activating, deactivating, or performing some other action with respect to the target with which it is in communication.
“Fusible Link” refers to a portion of a circuit in a IC which becomes permanently disabled, i.e. unable to carry current, when the current-carrying capacity of the Fusible Link is exceeded. It will be understood that other devices may be used to permanently transition from a first state to a permanent second state, such as a partial fuse or an anti-fuse.
“IC” refers to an electronic device which has data processing capabilities and an interface for communicating with other devices via electromagnetic signals, preferably RF signals. ICs are also in communication, preferably electrical communication, with a target. ICs can be directly attached to a target, such as by being embedded in a target, or can be attached to another article which is itself attached to the target. ICs typically comprise a silicon die containing integrated circuitry, with gold plated pads for wire connections to such circuitry. This form of the IC is often called a “die” or “chip” which are typically housed in “package” that can be fabricated from metal, plastic, or ceramic. The package protects the delicate die or chip and the associated bond wires, and it provides a standard way of making connections. Both packaged and raw or unpackaged dies with suitable connection means can be used. The term “embedded processor” or EP used in other provisional patent applications filed by Kestrel Wireless has the same meaning as that given to IC herein.
“Network Operations Center” or “NOC” refers to a facility for communicating with an IC, such as via a reader, and with a device running a load center application. The NOC comprises a server, computer, or other device having data processing capability and the ability to communicate with the IC and load center, preferably via a network connection. Functions of the NOC can be distributed over multiple locations and/or devices.
“Reader” refers to a device which provides an input signal, preferably an electromagnetic signal, to a RFA IC or other IC. If a RFA IC emits an electromagnetic signal in response, the reader is preferably configured to receive and process such signal. The overall function of a reader is to provide the means of communicating with RFA ICs and facilitating data transfer to and/or from RFA ICs.
“RF” refers to radio frequency energy.
“RFA IC” and “radio frequency activated integrated circuit” refer to refer to an IC having an interface for receiving input signals from a reader, which is also preferably capable of providing output signals to a reader. Radio frequency signals are preferred for the input interface but other types of signals, including electromagnetic signals of other frequencies, are also possible. RFA ICs are in communication with a target and also have an output interface to effect a change in a target. The RFA ICs described herein typically include a Fusible Link and other circuitry for permanently disabling the ability of an RFA IC to perform functions such as activating or deactivating a target. RFA ICs can be active, i.e. powered by a battery or other power source, but preferably are passive and obtain operating power from signals sent by a reader, without a separate external power source. RFA ICs can be manufactured in ways known to the art for producing integrated circuits for RFID tags and similar devices.
“Target” refers to an article, item or media on or to which an IC is to perform an action. Targets can be, for example, media for storing content such as audio, video, images, codes, and other types of data and information, in particular optical media such as compact discs (CDs), video discs, digital versatile discs (DVDs), laser discs, or holograms. Alternatively, the target can be an electronic device. ICs are typically embedded in a target.
As used herein, the term “comprise” and variations of the term, such as “comprising” and “comprises,” are not intended to exclude other additives, components, integers or steps. The terms “a,” “an,” and “the” and similar referents used herein are to be construed to cover both the singular and the plural unless their usage in context indicates otherwise.
RF Devices
Various IC devices makes use of RF frequency energy to communicate. Such devices are frequently referred to as RFID tags or similar designations. Such RF devices can be thought of as comprising three basic elements: an IC, an RF transmitter/receiver (“transceiver”) and an antenna. The antenna is typically electrically coupled to the IC through the transceiver. The functions of such devices are conventionally integrated into a single physical entity, but as described herein they can be distributed among multiple entities and in different configurations. For example, the antenna, transceiver and IC can all be embedded in a target, or the antenna can be coupled to an IC embedded in the target using appropriate mechanical and electrical connection means. In the latter configuration, the transceiver can be located with either the antenna or the IC. Typically, the IC is embedded in a target in the present systems. Various configurations of the foregoing elements are possible, such as multiple antennas coupled to a single IC, or multiple ICs configured to a single antenna.
RFA ICs are similar to an RFID tags, but are enhanced with elements not found in typical RFID tags. For example, RFA ICs generally include logic, memory and an output interface distinct from the RF interface to effect changes to a target to which it is coupled (e.g. to activate or deactivate the target to which it is coupled).
In most instances radio frequency communication is the preferred method of wireless communication between a reader and a target. Standard RF frequencies used in RFID applications are typically 13.56 MHz, 900 MHz ISM band, or 2.4 GHz. Although any frequency can be used, the 900 MHz ISM band is well suited for the present applications for reasons of antenna size, RF communication range, and minimal interference from other RF sources. Although the RF frequency energy shall be referred to throughout the present description, other electromagnetic frequencies are also possible. Therefore, references to RF (e.g., RFID, RFA IC, etc.) shall be understood as encompassing the use of other frequencies of electromagnetic energy unless otherwise noted, or unless other frequencies would not be feasible in a particular embodiment.
ICs and Antennas
Optical discs are one type of target for which the present systems are useful. However, it should be understood that the present systems are not limited to optical discs and that they are applicable to a wide range of targets. Content stored in an optical disc is read by reflecting a laser light off metalized data structures within the disc (one or more thin layers of metal that are deposited onto the surface of binary patterns molded into polycarbonate). Patterns in the reflected light are detected by an optical drive as the disc is rotated and are then translated into digital signals appropriate to the host device (e.g. computer, player or game console).
It is often desirable for the IC to be embedded in the optical disc. This ensures that the ID and any information contained within the IC are unequivocally associated with the particular disc to which it is embedded (as opposed, for example, to the case in which it is packaged). It also ensures that it can not be removed and that it can be coupled to other elements in the disc required, for example, to affect conditional access or activation.
ICs and Antennas in the Clamping Area of a Disc
To avoid interfering with the data structures in the disc, it can be desirable to locate the IC in the clamping area 86. This can be accomplished by embedding the IC in the polycarbonate substrates when the disc is molded or after the substrate is created and placing it in a space formed during the molding process or created afterwards (e.g. by laser drill, pressed indentation etc.).
Independent of the exact location of an IC embedded in the disc, it can be desirable to locate the antenna 88 in the clamping area 86 of the disc, as illustrated in
There are several ways that an antenna can be located in the clamping area. The antenna can be constructed out of conductive ink that is screened or sprayed on a surface of the polycarbonate substrate, including surfaces that are subsequently sealed or covered, e.g. when the two halves of the disc are bonded together. The antenna can be constructed out of metal that is directly deposited on the polycarbonate substrate of the optical disc. A foil antenna can also be pressed directly onto the polycarbonate substrate (e.g. on the side of the substrate to be bonded) or applied using an adhesive. A polycarbonate ring 89 or other suitable material with the antenna 88 already on it can be located in a matching recess 90 in the optical disc 85 as shown in
The antenna 101 along with the IC 105 is completed encapsulated within the disc 100 once the two halves are bonded together with the adhesive 109. The IC 105 can be mounted in the recess 106 with the contacts 110 toward the adhesive layer 109. The antenna 101 circuit, which can be screened conductive ink, overlaps 111 these contacts 110 to make connection to the IC 105. A slight recess 112 in layer 0 107 accommodates the thickness of the antenna 101.
It can be desirable to mount the IC in a recess in Layer 0. This can be easily accomplished by changing the molds for the polycarbonate blanks for layer 0 and layer 1.
Referring to
In different implementations, the antenna can be adhesively attached such that it is permanent, i.e. cannot be removed without damaging the substrate to which it is attached, or it can be removed by the customer after the activation process has occurred. This can occur through a direct action by the customer (e.g. manually pulling a label to which an antenna is attached off the disc), or it can be achieved automatically when the case containing the optical disc is opened and/or the optical disc is removed from the case. For example, the label with the antenna can be located on the bottom of Layer 0, which is always inserted down in the case. The adhesive that holds the label / antenna to the disc can allow the label to easily be pulled off. The back side of the label which contacts the inside of the case can be coated with a very aggressive adhesive, such as an acrylic adhesive. When the customer removes the disc from the case after activation, the label and antenna peel away from the disc and remain in the case. In a second example, the label with the antenna can be located on the top of Layer 1, which is always inserted up in the case. The adhesive that holds the label / antenna to the disc can allow the label to easily be pulled off. The top side of the label which contacts the inside of the case cover can be coated with a very aggressive adhesive, such as an acrylic adhesive. When the customer opens the case after activation, the label and antenna peel away from the disc and remain in the top cover of the case. The use of removable antennas can address consumer concerns about privacy and can be desirable from a marketing perspective.
The antenna may also be directly attached to the surface of the disc. For example, the antenna may be disposed on the surface using known deposition processes, or through an ink-jetting process that disposes a conductive ink in the form of an antenna pattern. The antenna may also be constructed of a foil or metal and be embedded in the surface, or adhered with an adhesive.
Antennas Associated with Cases
In another embodiment, an antenna can be located in or on packaging, such as a case that holds or contains an optical disc. The antenna can be electrically coupled into the disc via any number of methods, including but not limited to direct electrical connection via contacts, capacitive coupling via conductive pads or plates, magnetic coupling via coils or conductors, or any other appropriate method compatible with the RF carrier and modulation frequencies.
One example of this embodiment 150 is shown in
In
In all of the implementations described in FIGS. 9 to 14, the antenna conductors can be manufactured as part of the case itself. The conductors can be physical wires embedded or bonded to the case, or can be screened on with conductive inks or metals. They can also be implemented on a separate substrate such as polyester, Kapton, or any other suitable material, that is adhesively bonded to the case. If they are adhesively attached as a separate substrate, with the appropriate adhesive, then they can be removed after activation which can be an advantage due to privacy concerns. Note that in all of these examples that any suitably effective antenna geometry can be used.
Multiple Antennas Associated with Cases
All of the implementations described in FIGS. 1 to 14 are for a single antenna in one plane. Single, round or rectangular, loop antennas tend to be directional with strong lobes perpendicular to the plane of the loop, and nulls in the plane of the conductors. This directionality can be improved by using more than one antenna. A novel approach 275 to combining antennas is shown schematically in
In practice, the two antennas 277 and 278 can be oriented at right angles to one another, so that nulls do not occur along the plane of a single antenna. The matching networks, diodes D1281 and D2282, and the demodulator capacitor Cd 284 can be located on the antenna itself. The demodulated signal which only carries the modulation frequency spectrum, and not the RF carrier, can now be coupled into the IC on the optical disc via a relatively long interconnect 280. An example of this is shown in
An alternate implementation of this concept is shown in
Having dual antennas can facilitate reading or activating a carton of optical discs oriented edgewise on pallets or shelving. Reading or activating discs or simply reading cartons or other packaging at the check-stand can also be enhanced due to the two plane coverage offered by the configuration, which can make it less sensitive to orientation. After a read or activation the antenna on the case can be removed to address privacy or other concerns. The second antenna 304 located on or embedded in the optical disc can be used for additional conditional activation of content on the optical disc, in conjunction with an appropriate device to read and write to the IC.
For example, discs, or more precisely the ICs embedded in the discs, can be read using first antennas located on the edges of the cases containing the discs within a carton on a pallet at a retailer's shipping and receiving dock. A reader at the check-stand can ‘activate’ an individual disc using the first or second antenna. At home the consumer can remove the first antenna (decouple it from the disc) when the case is opened and use the disc in the conventional manner. Later, however, a second antenna embedded in the disc can be used to communicatively couple with other devices (e.g. to conditionally activate features on the disc, affect security schemes, access information stored in the IC, etc.).
Referring back to
The three dimensional corner cube arrangement of the triple antenna 330 shown in
A variant of the corner cube can be implemented as shown by the case 375 in
A further implementation of the triple antenna is shown in
Modified IC for Use with Antennas
In all of the variations described so far, the antennas all require external demodulator circuits in order to accommodate the relatively long leads between the actual antennas and the IC. However, in the situation of an embedded antenna on the disc as shown in
Although the present invention has been discussed in considerable detail with reference to certain preferred embodiments, other embodiments are possible. The steps disclosed for the present methods are not intended to be limiting nor are they intended to indicate that each step depicted is essential to the method, but instead are exemplary steps only. Therefore, the scope of the appended claims should not be limited to the description of preferred embodiments contained in this disclosure. All references cited herein are incorporated by reference to their entirety.
While particular preferred and alternative embodiments of the present intention have been disclosed, it will be appreciated that many various modifications and extensions of the above described technology may be implemented using the teaching of this invention. All such modifications and extensions are intended to be included within the true spirit and scope of the appended claims.
This application claims priority to U.S. patent application No. 60/699,411, filed Jul. 13, 2005, and entitled “Wireless Communication with Optical Discs”, which is incorporated herein in its entirety.
| Number | Date | Country | |
|---|---|---|---|
| 60699411 | Jul 2005 | US |
