Jamming device against rfid smart tag systems

<u style="single">TECHNICAL FIELD OF THE INVENTION</u>

The present invention relates generally to the field of RFID technology, and more particularly to a jamming device against RFID systems. <patcit id="pcit0001" dnum="DE29714999U1"><text>DE 297 14 999 U1</text></patcit> discloses a prior art device four the protection of a transponder against unauthorised readers. <patcit id="pcit0002" dnum="US6429768B1"><text>US 6,429,768 B1</text></patcit> discloses a prior art radio frequency jammer for preventing the transponder reader of a vehicle immobiliser from receiving signals from a transponder such as an ignition key.

<u style="single">BACKGROUND</u>

Radio Frequency Identification Devices (RFIDs) are low-cost, passive "smart" chips or "tags" that can be embedded in or attached to articles, products, and the like to convey information about the product via a scanner. The smart tags are generally small label-like devices with a microchip and a miniature embedded antennae. The tags may be passive or active, the active tags requiring an internal power supply. A reader or scanner interrogates the smart tag with an electronic "trigger" signal. The tag in turn generates an electromagnetic pulse response that is readable by the scanner, the response containing the product information. RFID smart tags can be embedded in or attached to product packaging, or incorporated directly into the product, and may convey conventional "bar code" information, as well as other more detailed information.

Various commercial applications have been suggested for smart tags, particularly in the area of retail marketing and sales. For example, RFID technology may be used to gather information related to consumer trends, purchasing habits, consumption rates, etc. It has also been suggested that RFID technology has promise in the areas of inventory control, manufacturing process and control, product accountability and tracking systems, etc. Manufacturers, shippers, and retailers may be able to follow a given product through their respective systems from initial production through to point of sale. It has been suggested that other applications may include shopping carts that automatically charge a bank account, refrigerators that tap into the Internet to automatically reorder items that are running low, and interactive televisions linked to such refrigerators that will feed targeted commercials and special offers to consumers. (See, "<nplcit id="ncit0001" npl-type="s"><text>They Know What You Eat," by Kayte VanScoy, Smart Business, January 2001</text></nplcit>).

Although RFID technology may provide benefits to the commercial sector, certain individuals may view particular uses of the technology as intrusive and an invasion of privacy. For example, some consumers refuse to use of "loyalty" cards at supermarkets even if a significant discount is offered because they object to the notion that their purchases are being tracked and analyzed. Such consumers may be less than enthused at the possibility that smart chips or tags embedded in their clothing, for example, may disclose their purchasing habits or likes and dislikes when they walk past a smart tag scanner at the entrance of a store. Consumers may object to being selectively targeted by telemarketers or mass mailings based on the smart tagged products they purchased at a store.

The present invention relates to a novel implementation of jamming devices to inhibit unwanted intrusions of RFID technology.

<u style="single">SUMMARY</u>

Objects and advantages of the invention will be set forth in the following description, or may be obvious from the description, or may be learned through practice of the invention.

The present invention provides a RFID technology jamming system and method to inhibit unwanted intrusions of RFID technology into an individual's personal life. The device and method of the present invention is intended to prevent RFID smart tag systems from detecting and identifying products purchased or worn by an individual, or otherwise associated with or belonging to an individual. The present invention provides a jamming device as set forth in claim 1 which is characterised over the disclosure of <patcit id="pcit0003" dnum="DE29714999U1"><text>DE 297 14 999 U1</text></patcit>.

A jamming device in accordance with an embodiment of the present invention comprises a passive device comprising a structure containing a large number of RFID chips. When the chips are "excited" by a trigger excitation signal from a nearby scanner, the chips simultaneously generate an electromagnetic response pulse. The number of chips is so great that the scanner is overwhelmed by the response pulses and cannot read the multiple responses rapidly enough and discriminate between these responses and any "legitimate" responses generated by any product smart tags.

The structure containing the RFID jamming chips is not limited in any manner and, desirably, may be disguised as any type of item typically carried or worn by a consumer- For example, the structure may be configured to look like a cellular telephone, pager, camera, or the like. The passive jamming device may have a size so as to fit within a pocket, purse, briefcase, backpack, belt, pen, button on an item of clothing, a shirt label, a shoe, a dental filling, a wristwatch, and so forth. Ways in which to hide or disguise the passive jamming device will be readily apparent to those of skill in the art.

In one embodiment, the jamming device can be activated or deactivated at the will of the user to prevent others from scanning smart tags except under certain circumstances. For example, some users of smart cards containing personal and financial information may fear that others may use scanners to obtain their personal information (e.g., account numbers and access codes), Such smart cards can be protected with a jamming device that is turned off when the smart card is to be used by a legitimate scanner. Passive jamming devices may employ antennas that can be disabled or disconnected by actions such as squeezing or bending a flexible card, pulling a tab, pressing a button, and the like, or the passive jamming device may be shielded by a Faraday cage, a metal cover, or a layer of dense material such as concrete, or may simply be removed from the presence of the smart card or other objects comprising smart tags when the user wishes to allow the smart tags to be scanned. For example, an automated teller at a bank adapted to read smart tags in a smart-card may be equipped with a shielding device into which a jamming device can be temporarily placed to prevent jamming, or there may be removal means such as a pneumatic tube or conveyor system to momentarily allow the jamming device to be carried a distance away from a smart tag reader to prevent jamming.

Additional aspects of the present methodology and system will be described below with reference to the figures.

<u style="single">BRIEF DESCRIPTION OF THE DRAWINGS</u>

<ul id="ul0001" list-style="none" compact="compact"><li><figref idref="f0001">Figure 1</figref> is a graphic illustration of concepts according to a method and system of the invention.</li><li><figref idref="f0002">Figure 2</figref> is a graphic illustration of a passive RFID jamming device according to the intention.</li></ul>

<u style="single">DETAILED DESCRIPTION</u>

Reference will now be made in detail to one or more embodiments of the invention, examples of which are graphically illustrated in the drawings. Each example and embodiment are provided by way of explanation of the Invention, and not meant as a limitation of the invention. For example, features illustrated or described as part of one embodiment may be utilized with another embodiment to yield still a further embodiment. It is intended that the present invention include these and other modifications and variations.

RFID smart tag technology is known and understood by those skilled in the art, and a detailed explanation thereof is not necessary for purposes of describing the method and system according to the present invention. A typical smart tag detection configuration is depicted generally in <figref idref="f0001">Figure 1</figref>. Conductive or passive micro memory chips ("smart tags" 14 may consist of a microchip comprising silicon or other semiconductors, a coiled, etched, or stamped antennae, a capacitor, and a substrate on which the components are mounted or embedded. A protective covering is typically used to encapsulate and seal the substrate. inductive or passive smart tags have been introduced by Motorola under the name "BiStatix". A detailed description of the BiStatix device may be found in <patcit id="pcit0004" dnum="US6259367B1"><text>U.S. Patent No. 6,259,367 B1</text></patcit>. Another commercial source of suitable smart tags is Allen Technology Corporation of Morgan Hill, California, under the technology name FSA (Fluidic Self-Assembly). With the FSA process, tiny semi-conductor devices are assembled into rolls of flexible plastic. The resulting "smart" substrate can be attached to or embedded in any variety of products. The smart tag technology under development at the Auto-ID Center at Massachusetts Institute of Technology (Cambridge, Mass.) can also be used within the scope of the present invention. Further information on smart tags and related technology is disclosed in <patcit id="pcit0005" dnum="US6451154B"><text>US Patent No. 6,451,154</text></patcit>, "RFID Manufacturing Concepts," issued Sep. 17, 2002 to Grabau et al.; <patcit id="pcit0006" dnum="US6354493B"><text>US Patent No. 6,354,493</text></patcit>, "System and Method for Finding a Specific RFID Tagged Article Located in a Plurality of RFID Tagged Articles," issued Mar. 12, 2002 to Mon; <patcit id="pcit0007" dnum="WO0248955A"><text>PCT publication WO 02/48955</text></patcit> corresponding to <patcit id="pcit0008" dnum="US2002070862A"><text>US 2002/070862</text></patcit>; <patcit id="pcit0009" dnum="US6362738B"><text>US Patent No. 6,362,738</text></patcit>, "Reader for Use in a Radio Frequency Identification System and Method," issued Mar. 26, 2002 to Vega;<nplcit id="ncit0002" npl-type="b"><text> D. McFarlane, "Auto-ID Based Control," White Paper for the Auto-ID Centre Institute for Manufacturing, University of Cambridge, Cambridge, United Kingdom, Feb. 1, 2002, available at hftp://www.autoidcenter.org/eesearch/CAM-AUTOID-WH-004.pdf</text></nplcit>; and <nplcit id="ncit0003" npl-type="b"><text>Chien Yaw Wong, "Integration of Auto-ID Tagging System with Holonic Manufacturing Systems," White Paper for the Auto-ID Centre Institute for Manufacturing, University of Cambridge, Cambridge, United Kingdom, Sept. 2001, available at www.autoidcenter.org/research/CAM-WH-001.pdf</text></nplcit><u style="single">.</u>

Other examples of commercial RFI D systems include those marketed by Microchip Technologies (Chandler, Arizona); the I*CODE chips and readers of Philips Semiconductor (Eindhoven, The Netherlands); the RFID products of Sokymat (Lausanne, Switzerland); the TI*RFID^™ Systems and Tag It^™ chips of Texas Instruments (Dallas, Texas); and the products of Gemplus (Gemenos, France), Nedap (Groenlo, The Netherlands), Checkpoint Systems Inc. (Miami, Florida), and Omron Company (Tokyo, Japan). High frequency bands can be used, exemplified by the 2.45 GHz products of SCS Corporation (Rancho Bernardo, California.

A related technology within the scope of the present invention is Surface Acoustic Wave (SAW) technology. For example, InfoRay (Cambridge, Massachusetts) markets a passive smart tag that is said to achieve long ranges (up to 30 meters) using a Surface Acoustic Wave (SAW) device. On a chip coupled with an antenna. The SAW device converts a radio signal to an acoustic wave, modulates it with an ID code, then transforms it to another radio signal that is emitted by the smart tag and read by a scanner. The ID code of the smart tag is extracted from the radio signal. The scanner is said to compare the spectral content of the signal with a database of signatures and to derive the ID code. This method enables a read range of up to 30 m (typical 10-20 m). The system can operate In the 915MHz band and 2.45GHz band. RFSAW, Inc. (Dallas, Texas) also provides minute Surface Acoustic Wave (SAW) RFID devices that can be used within the scope of the present invention. Smart tags can include read-write systems or write-only systems.

An embedded antennae within the smart tags 14 can be a useful component of the device, through it is recognized that alternatives to antennas may exist in some applications. For example, for some metallic objects, the smart tag need not comprise an antenna but the metallic object itself can serve as the antenna. An excitation trigger signal 18 from a RFID scanner 16 must be received by the antennae to "activate" the smart tag 14. The received excitation signal 18 is the power source for the smart tag 14 and results in the generation of an electromagnetic pulse containing a coded product Information signal 20. A detailed description of RFID smart tag antennas and technology may also be found In <patcit id="pcit0010" dnum="US6320556B1"><text>U.S. Patent No. 6,320,556 B1</text></patcit>.

For commercial applications, an RFID scanner must be able to read multiple signals from a plurality of smart tags and to discriminate and focus only on the signals of interest. The problem of RFID scanners encountering multiple signals has been recognized in the art. Anti-collision algorithms may be used to sort through multiple signals, but such systems have limitations. It is unlikely that RFID scanners can be reasonably equipped to process large numbers of simultaneous RFID signals, such as 1,000 or more, or 10,000 or more simultaneous signals. It is also unlikely from a commercial feasibility standpoint to equip RFID scanners with processing circuitry necessary to effectively handle the complexities created by active signal jamming that confuses the scanner with transient random signals, spot frequency jamming, or broadband barrage jamming. These inherent drawbacks of smart tag scanners can be exploited for purposes of creating effective jamming techniques.

As mentioned, Fig. graphically illustrates a typical smart tag detection system wherein smart tags 14. are attached or embedded in any manner of articles 12. A smart tag scanner 16 is disposed at a location to detect and interrogate products associated with smart tags 14 coming within range of the scanner 16. For example, the scanner 16 may be disposed at the exit or entrance to a store, departments within the store, checkout counters, etc. In the illustrated scenario, the scanner 16 is disposed so as to detect the types of products or-articles a consumer has purchased in a particular department, or is actually wearing in the case of embedded smart tags 14 in the consumer's clothes, etc. The scanner 16 may be operationally configured with any manner of computer network (graphically illustrated as computer 20) wherein the received and decoded product information signals are processed and analyzed for any number of reasons. Still referring to <figref idref="f0001">Fig. 1</figref>, the consumer may carry on their person a jamming device 30 in accordance with the present invention to inhibit the scanner 16 from effectively detecting smart tags 14 in any products purchased or otherwise associated with the consumer.

<figref idref="f0002">Fig. 2</figref> is a graphic representation of a passive RFID jamming device 30 in accordance with the teachings of the invention. The device 30 may be disguised as any conventional item or article that is typically and inconspicuously associated with consumers. For example, in the illustrated embodiment, the device 30 includes a structure 28 disguised as a conventional cellular telephone. This is for illustrative purposes only. The structure 28 may be disguised, for example, as any manner of consumer electronic item, such as a pager, camera, personal CD player, radio, etc. In an alternate embodiment, it is not necessary that the scanner 30 actually be visible. The jamming device 30 may be of a size and proportion so as to discretely fit within the individual's pocket, purse, briefcase, backpack, and the like.

Still referring to <figref idref="f0002">Fig. 2</figref>, the structure 28 defines an interior volume in which a plurality of RFID chips 32 are stored. The number of chips may, vary, but should be great enough so as to generate a sufficient number of random RFID signals to overwhelm the RFID scanner 16. The number of chips and signals will obviously vary depending on the type of RFID system and such number may be empirically determined. The present inventors contemplate that 10,000 or more chips may be sufficient to render current RFID scanner technology ineffective. However, it should be recognized that this number may be greater or larger depending on the RFID system.

Referring to <figref idref="f0001">Fig. 1</figref>, as the consumer 30 approaches or comes within range of the scanner 16, the scanner's excitation trigger signals 18 "excite" or activate the plurality of jamming chips 32 causing each chip 32 to transmit an electromagnetic pulse signal 20. The plurality of pulse signals 20 are received by the scanner 16 and are of such a large number so as to prevent the scanner 16 from effectively detecting or recognizing legitimate product information signals 20 transmitted by any product associated smart tags 14.

It should be appreciated that the RFID jamming system and methodology according to the invention is not limited to any particular scenario. The jamming device may be used wherever an individual desires to inhibit smart tag technology from intruding into the individual's private life.

It should be appreciated by those skilled in the art that the system and method according to the invention have wide applications, and that the example and embodiments set forth herein are merely exemplary. It is intended that the present invention include such uses and embodiments as come within the scope of the appended claims.