This invention relates generally to configuring a wireless device for communications with a receiver, and in particular, to using a radio frequency identification system to create a virtual communications link between a wireless device and a receiver.
Due to the widespread proliferation of wireless technology, it is now commonplace for multiple device-receiver pairs to be operating within the same frequency band in a single home or workplace environment. This has led to a greater risk of interference, both intentional, in the form of malicious eavesdropping, and unintentional, due to crosstalk between devices. An additional security threat may also be associated with remote-controlled devices that are susceptible to being manipulated by multiple wireless transmitters. One common technique to ensure that signals are received exclusively by their intended receiver within signal rich environments is to establish a unique identifier or address between each receiver-transmitter pair. This technique reduces the likelihood of interference and security risks associated with the technique previously described. The identifier is embedded in the signal transmitted from the sending device. The corresponding receiving device will only accept, report on, or otherwise react to received signals containing the correct identifier code. Signals received by the receiving device that do not contain the appropriate identifier code are ignored so there is no erroneous reporting by the receiving device.
This technique requires that a predefined identifier be stored in the * transmitting device. Conventionally, this can be accomplished by writing a unique address or identifier into read-only memory (ROM) (e.g., electronically erasable programmable ROM or EEPROM) of the transmitter and receiver. During the manufacturing process, for instance, the predefined identifier code is programmed into the EEPROM of the transmitter-receiver pair. The predefined identifier code will then be available when the sending device transmits data. The EEPROM can add substantial cost due to the EEPROM itself, the manufacturing process involved in placing and programming the EEPROM, and the physical space consumed by the EEPROM. A second drawback of this approach is that different components of the transmitter-receiver pair may be manufactured in different locations and at different times, to be matched to each other just prior to distribution or be distributed unmatched, requiring the user to complete the matching process. For instance, in the computer peripherals context, a receiver may be made at a distribution center in Europe, to be coupled with a keyboard assembled in Thailand and a mouse from China, and used with documentation manufactured by a local vendor. Matching the unique codes to components adds considerable administrative overhead and coordination between manufacturing sites.
Techniques have been devised to provide the code to the components post-distribution, for instance by using an auto-connect button that allows peripheral components to tune into each other while at the client site. However, such approaches may often be undesirable because they require the user to program their own devices prior to using them, imposing a configuration burden on the user and technical support costs on the supplier. In addition, in corporate environments where multiple transmitter-receiver pairs may operate within a small range, there is a chance that a device will be misprogrammed and associated with the wrong receiver or transmitter.
What is needed, therefore, is a technique that allows an identifying code or other virtual link to be distributed to transmitter-receiver pairs in a way that can be accomplished with minimal coordination and does not require user intervention. The technique should be implementable at the end of the supply chain, when components groups are coupled together into wireless systems just prior to distribution.
In an embodiment, two devices of a wireless system can be communicatively associated using a unique identifier stored on a radio frequency identification (RFID) system. For example, code can be written to a first RFID tag in a first wireless device and to a second RFID tag in a second wireless device. The common code couples the two devices to each other, and can be used to identify one device to the other during communication. The step of writing to one or both of the RFID tags can be performed during the last stage of production when the devices of a wireless system are brought together. Because an RFID tag can be written to and energized wirelessly by a writer/reader, without requiring its own power supply, this step can flexibly be performed virtually at any time, including just before distribution eliminating the need to coordinate between production facilities in disparate locations.
Code written to an RFID tag can comprise any number of types of identifying data such as an address associated with the receiver or a key shared with the receiver. In an embodiment, a signal sent from the transmitter to the receiver can include the code or a variant of it to distinguish the signal's source. The RFID tag may be mounted to the printed circuit board of a device, and commands contained in the signal can be transferred over a signal line to be processed accordingly. In one embodiment, a common code is written to two devices; in another embodiment, however, a code can be read from a first RFID tag within the first device, and written to a second RFID tag within the second device. That way, the first RFID tag can be of the less expensive read-only tag class. When more than two devices are to be coupled together, for instance, in the case of one receiver and two transmitters, the devices may share a common code, written to each according to an anti-collision protocol.
An embodiment of the invention can be implemented in any wireless transmitter-receiver pair (e.g., mouse, keyboard, video camera, personal digital assistant, pointing device, remote control, etc) or system including more than one receiver or transmitter. It may be accomplished through a system comprising an RFID writer. The system may also include a reader, implementable for instance in a single writer/reader, in order to also verify that code written to an RFID tag is well-formed.
The features and advantages described in the specification are not all inclusive and, in particular, many additional features and advantages will be apparent to one of ordinary skill in the art in view of the drawings, specification, and claims. Moreover, it should be noted that the language used in the specification has been principally selected for readability and instructional purposes, and may not have been selected to delineate or circumscribe the inventive subject matter.
The invention has other advantages and features which will be more readily apparent from the following detailed description of the invention and the appended claims, when taken in conjunction with the accompanying drawings, in which:
Figure (or FIG.) 1 depicts a computer system including wireless peripheral components for use in accordance with an embodiment of the present invention.
While the present invention will be described in connection with preferred embodiments thereof, it will be understood that it is not intended to limit the invention to those embodiments. On the contrary, it may not cover all alternatives, modifications, and equivalents as may be included within the spirit and scope of the invention as defined by the appended claims.
Reference will now be made in detail to several embodiments of the present invention(s), examples of which are illustrated in the accompanying figures. It is noted that wherever practicable, similar or like reference numbers may be used in the figures and may indicate similar or like functionality. The figures depict embodiments of the present invention for purposes of illustration only. One skilled in the art will readily recognize from the following description that alternative embodiments of the structures and methods illustrated herein may be employed without departing from the principles of the invention described herein.
RFID Auto-Connect System
In an embodiment, the RFID tags 300 are passive tags that can be encoded by an RFID writer without the need for an external power supply. Electromagnetic waves sent by a writer generate a current in the antennae of the tags 300 to power the microchip circuit and send a return signal to the writer. The writer can write the same address to the tags 300 within each device without any need to put the battery in those devices. This affords great flexibility in manufacturing operations, as, for example, the tags 300 can be inserted onto the printed circuit boards of wireless components 120, 130, 140 at one or more stages of production, and then encoded at the end of production when the components 120, 130, 140 are assembled together into a wireless system. This avoids the need to coordinate codes between the components 120, 130, 140 at an earlier stage in production, an administrative challenge when the components 120, 130, 140, are manufactured separately in different facilities and/or at different times, as is commonly the case.
RFID Tag
The system architecture configuration shown in
The RFID tag 300 includes an antenna 310 for transmitting and receiving electromagnetic waves and a microchip 320 for storing information and doing simple processing. Although the antenna 310 shown is a rectangular antenna, it could also comprise a circular or loop antenna, an air coil antenna, or a printed antenna comprised of carbon paper ink. In an embodiment, the antenna 310 is positioned to optimize access by an RFID writer, for instance, on a production line. The RFID tag 300 may be coupled to the memory 155 by a data bus and can store identifier or other values provided by an RFID writer to the memory 155. In another embodiment, the RFID tag includes a small amount of memory and is coupled to the CPU 150 by a data bus line by which the CPU 150 can access the memory. Alternatively, the RFID tag 300 may be coupled to a memory 155 over an air interface.
In the alternative PCB configuration shown in
The RFID tag 300 can be based on any existing or emerging RFID technology. The RFID tag 300 can be read-only, read/write, active, passive, semi-passive, or be of any of a variety of existing or emerging categories of RFID tags. The RFID tag 300 may have varying dimensions and be configured, for example, like a SO8 package or TSSOP8 package. Further, in one embodiment the RFID tag 300 is designed to operate at around 13.56 MHz and have a transmission and/or reception range of, for example, between 25 to 50 centimeters. Other frequencies and ranges are also possible including, inter alia, 125 KHz with a range below 10 cm, 915 MHz with a range between 3 to 5 meters, and 2.45 GHz with a range between 0.5 to 1 meter. Alternatively, a nonstandard frequency for RFID such as 27 MHz maybe used, as permitted by international regulation.
In accordance with an embodiment of the invention, an identifier or code is written to the RFID tag 300 that is used to couple the wireless device associated with the RFID tag 300 to other devices. The identifier or code can comprise a SHORT_ID that could, for example, describe the model of the devices (e.g. reflecting the number of buttons or feature set) and can follow any number of data formats. Alternatively, the identifier can consist of a multiple-bit address associated with the receiver, included directly in the transmissions of transmitters in peripheral devices.
In another embodiment, the identifier is used to seed a code-generating algorithm known to both a receiving and transmitting device, the result of which is included in transmissions between the receiving and transmitting device. The algorithm may comprise an encryption algorithm, and the RFID tag of a transmitter (e.g. stored in the keyboard of
In yet another embodiment, one or more of the RFID tags 300 holds cryptographic protocol data, for use in encoding wireless transmissions. The information stored to the RFID tags 300 could alternatively comprise data for pairing the devices according to a Bluetooth protocol, or identification data to be used in tracking the wireless devices, including production or certification data to avoid product counterfeiting. In an embodiment, a single common identifier is stored to RFID tags 300 within each of the multiple components within a single wireless system; in another embodiment, different identifiers are stored within different wireless peripherals. For instance, RFID tags 300 within wireless keyboard 130 and mouse 140 are encoded with different identifiers, both of which are coded to RFID tag 300 within computer 120, in order to distinguish between the transmissions sent to computer 120 from the different components.
Programming RFID Tags of a Wireless System
At stage B, the writer of the reader/writer 410 in the pairing station wirelessly writes a code or identifier to RFID tags included in a box 430B. The code or identifier may be randomly generated or serially assigned according to a manufacturing protocol. In an embodiment where the code comprises an ID and encryption key, the writer 410 may be coupled to or include a processor for generating a random key, of various encryption key lengths, using conventional methods known in the art such as a pseudo-random number generator, hash algorithm or microcontroller hardware timer. After the code has been written to the RFID tags, the reader of reader/writer 410 verifies the code written to each tag to ensure that it is well-written. Reader/writer 410 could comprise a handheld device, and/or be positioned in a variety of configurations and is located within range of RFID tags included in box. An advantage of using the RFID reader/writer 410 is that it writes to and reads from the RFID tag through RF waves and thus does not require direct access or line of sight to the tags. Taking advantage of this feature, in one configuration the RFID reader/writer 410 writes the common identifier to the tags through a closed box.
In another embodiment, to enable the devices to interoperate with other Bluetooth devices, the pairing station generates a random PIN (personal or private identification number) code for each of a wireless keyboard 130 and a wireless mouse 140. The writer of the reader/writer 410 is used to write these codes to each of the devices 130, 140. The reader of the reader/writer 410 is used to read the Bluetooth addresses from each device and writes the addresses and the PIN codes associated with the keyboard 130 and mouse 140 to the RFID tag in the receiver 101.
In another alternative embodiment of the invention, the identifier is written to the memory of a wireless device using a temporary wired network, rather than wirelessly. This could be still be accomplished while the wireless device is already packaged through a special conduit in the housing for the device, or access points such as plugs or holes in the device packaging. In addition, an optical link could be used to provide the coupling data to the devices.
A pairing system 700 as shown in
In another embodiment, pairing is done after the devices have been shipped to an end-user, rather than during the production process. The receiver of a transmitter-receiver pair is equipped with a low-power RFID writer and/or reader that broadcasts read/write signals over a small range. When the receiver and a peripheral are brought within close proximity of each other, the writer within the receiver writes identifying data such as a numerical identifier or shared encryption key to an RFID tag stored within the peripheral device. The receiver and peripheral are paired. Advantageously, this allows peripheral and other devices and transmitters to be sold separately or matched from different systems. Thus, a user can buy a peripheral gaming accessory or a replacement peripheral and couple it to her existing gaming system.
A variety of pairing protocols is possible. For instance, separate and distinct IDs may be written into each peripheral device 130, 140 and these IDs written to an RFID tag of a receiver 150. The receiver 150 can identify commands sent by a wireless keyboard 130 because they include the code uniquely associated with the keyboard 130; likewise, signals sent by a mouse 140 can be distinguished by the separate code provided for communications sent from the mouse 140. In certain embodiments, the reader portion of the reader/writer 410 may be omitted, in others, the functionality of the reader/writer 410 may be provided by multiple devices.
In an embodiment, an RFID tag contained in a receiver device 150 is a read-only tag that already contains an identifying value. A reader of the reader/writer 410 reads this value from the RFID tag on receiver device 101 and a writer of the reader/writer 410 in turn writes the identifying value to RFID tags on the wireless keyboard 130 and wireless mouse 140. In order for the reader of the reader/writer 410 to read the identifiers written to the various devices (i.e. the keyboard 130, mouse 140, and receiver 101) the reader/writer 410 and tags follow an anti-collision protocol in order to distinguish between RFID signals sent from the various devices 130, 140. This anti-collision protocol can be implemented according to a singulation protocol under which tags take turns transmitting to the reader of the reader/writer 410. Following such a protocol, the reader of the reader/writer 410 may send various switch-on, switch-off, acknowledge, and retry signals to tags in wireless devices 130, 140, 150. Responsive to these signals, signals may be broadcast by antennae of RFID tags at varying times. In one embodiment, each RFID has its own unique identifier and the reader can choose the RFID tag with which the reader wants to communicate. Alternatively, each RFID has one of a set of identifiers that the reader and/or writer of the reader/writer 410 use to specify the intended recipient of the signal. A binary tree scanning anti-collision protocol which implements the “reader talks first” methodology well-known in the art may also be used. Under such a protocol, no tag transmits any information prior to a request by a reader.
In another embodiment, peripheral devices operating at different frequencies can communicate with the receiver according to a standard such as Bluetooth, Shared Wireless Access Protocol (SWAP), IEEE 802.11, or IEEE 802.15. Alternatively, a wireless bridge can be used to accomplish pairing. Various wireless bridges are described in more detail in U.S. patent application Ser. No. 09/507,768, which is herein incorporated by reference in its entirety. Using any of these methods or systems, a user could send a print command from a handheld device to a receiver in a computer that is in turn coupled to a print server.
Production of an RFID Auto-Connect System
At the next stage in the process, wireless devices, in the example shown in
In an optional step, a pre-stored identifier value is read 525 by an RFID reader from an RFID tag in a first device. This identifier value is provided to an RFID writer, and is written 530 to RFID tags contained in the other elements of the wireless system. In another embodiment, step 525 is omitted, and a common identifier is written 530 by an RFID writer to read/write tags in all elements of the wireless system. The identifier is then read and verified 540 by an RFID reader. Once the information is verified 540, the information is blocked 545 for reading and writing, and the resulting lock is verified.
Steps in the process shown in
In addition, an embodiment may also be configured to allow one or more readers for use in tracking and monitoring, for example, an analysis of error logs of returned units or for tracking and detecting an uncertified device. In another embodiment, one or more RFIDs in the wireless system are programmed at one stage in the production and are used to track production of the wireless system during subsequent phases of the supply chain.
Operation of an RFID Auto-Connect System
Referring now to
The wireless transmitter generates 640 a communications signal that includes the communications code generated 630 based on the identifier and transmits 650 it to a receiver. In a system where there are multiple transmitters sending signals to a common receiver, the step of generating 640 a communications signal may be carried out in accordance with one of a number of possible protocols for distinguishing between signals sent from the different transmitters. For example, in an embodiment the format of the data field will vary with the type of wireless peripheral device and the type of message. Alternatively, headers may be used to identify to the user the type of device, including address or sub-address information relevant to the transmitting device. The communications signal is transmitted 650 and the source of the signal is identifiable by the code contained in the signal.
The foregoing description of the embodiments of the invention has been presented for the purposes of illustration and description. It is not intended to be exhaustive or to limit the invention to the precise form disclosed. Many modifications and variations are possible in light of the above teaching. It is intended that the scope of the invention be limited not by this detailed description, but rather by the claims appended hereto.
This application is a continuation of U.S. patent application entitled “RFID Auto-Connect for Wireless Devices,” to Monney et. al. attorney docket number 19414-9327, filed Sep. 22, 2004, which is hereby incorporated by reference in its entirety herein.