Abstract:
A system reduces the risk of eavesdropping on data used to access an establishment&#39;s computer network. In one embodiment, a system includes a personal area network (PAN) access device that couples a low power, low frequency modulated signal to a wearer, the PAN access device including a data storage unit for storing personal identification data including biometric data and a modulator for modulating a low power, low frequency signal with the personal identification data, a personal area network (PAN) receiver for receiving the modulated signal, a database for storing purchasing data for a plurality of customers, a memory including instructions which, when executed, associate the received personal identification data with the stored shopping data for one of the plurality of customers and a microprocessor for executing the stored instructions.

Description:
FIELD OF THE INVENTION 
   This invention relates generally to secure access devices for computer systems and, more particularly, to personal identification devices for computer systems. 
   BACKGROUND OF THE INVENTION 
   Computers are used in a variety of ways in retail establishments. They not only are used to implement payments but they are increasingly used to promote goods and services to users on the premises of the establishment. Typically, computers in a retail establishment may be used to attract a customer&#39;s attention to a store display and then generate electronic coupons or the like in an effort to entice the customer to accept some offer at the display. To identify customers so their buying habits and preferences may be monitored and analyzed, many stores are instituting preferred customer programs. In these programs, customers provide some identification data, such as a name and address, and receive a customer token that contains or bears a unique identifier. The token may be a hard polymer tag bearing a bar code that may be coupled to a customer&#39;s key chain. When the customer goes to a checkout terminal to pay for goods or services, the preferred customer token is typically scanned so the data regarding the goods and services purchased may be associated with the customer identification code. This data may be stored and later analyzed for determining customer buying patterns and other important marketing data for an establishment. 
   In those systems where electronic coupons are generated, the scanning of a preferred customer token may be used to capture the preferred customer identification code. This code may then be used to query a database and, based upon the customer&#39;s marketing data, coupon discounts may be offered. For example, customers who have spent an amount of money with the establishment that exceeds some threshold may be offered greater discounts than one who has not reached the threshold. This system may then be used to give incentive to customers to use their preferred customer tokens in a store. 
   One problem with computer systems that read customer identification data, either from preferred customer tokens or financial token, such as credit cards or the like, is the contact required for token reading. Systems that read bar codes require transparent platens and laser readers that need to be oriented for optimal reading of the bar code. Additionally, the expense of such optical readers may be cost prohibitive for distributing the readers at a plurality of sites in a large establishment. Also, customers may tire of pulling their key chains from their pockets or purses for scanning purposes and choose instead to pass the coupon offer station. Although wireless transmitters encoded with a customer identification code may be used, a number of issues arise from their use as customer tokens. For one, wireless transmitters typically have sufficient transmission range that the simultaneous activation of a plurality of transmitters in an enclosed area may result in signal interference. Another problem may arise where the code identified in the wireless signal corresponds to financial transaction codes or account numbers for a customer. Persons desiring to obtain such codes in an authorized manner may carry receivers with memory devices so they can surreptitiously receive the wireless signals and stored them for later analysis. 
   What is needed is a system through which a computer system may receive customer identification codes without requiring optical scanners or the like. 
   What is needed is a system that receive customer identification codes without making the data susceptible to eavesdropping. 
   SUMMARY OF THE INVENTION 
   A system and method that operates in accordance with the principles of the present invention overcome the above-noted limitations of previously known customer identification code receivers. The system of the present invention comprises a personal area network (PAN) access device that couples a low power, low frequency modulated signal to a wearer and a personal area network receiver for receiving the modulated signal. The personal area network access device includes a personal data storage unit and a low power data modulator. The low power data modulator modulates a low power, low frequency signal with the data from the storage unit. This signal is capacitively coupled to the wearer&#39;s body so it may be emitted to a PAN receiver. When the wearer brings a body part such as a finger in proximity to or in contact with the PAN receiver, the receiver may receive the modulated signal. The signal may then be demodulated to obtain the user data so it may be encoded in data messages provided to a server of an establishment computer system. The user data may then be used to access marketing data for the customer or to implement a financial transaction. An advantage of the PAN transmitter is that it may be incorporated within a piece of jewelry such as a watch, necklace, or bracelet as a wearable computer. Transmission of the modulated signal by the low power, low frequency signal emitted by the wearer&#39;s body helps reduce the opportunity for eavesdropping as the signal is not radiated at a distance that facilitates undetected eavesdropping. Thus, access to marketing and financial transaction data for a customer is made more secure by a system of the present invention. 
   In a preferred embodiment of the present invention, the wearable computer also includes a receiver for receiving financial data from a transmitter associated with the PAN receiver. The financial data may be used to update data within the wearable computer such as is stored in a smart card or the like. Additionally, the financial data may be discount data that may then be presented to a PAN receiver associated with a checkout terminal. 
   The method of the present invention includes modulating a low power, low frequency signal with user data and capacitively coupling the modulated signal to a user&#39;s body for transmission. The method may also include receiving the modulated signal and relaying the user data to a server for accessing customer marketing data or for implementing a financial transaction. The financial data may be data for updating an account stored in a wearable computer or it may be discount data that may be later presented to a PAN receiver associated with a checkout terminal. 
   It is an object of the present invention to reduce the likelihood of another eavesdropping on the transmission of a personal identification code used to access a computer network. 
   It is an object of the present invention to enable entry of a personal identification code without requiring contact of a token with a reader. 
   These and other advantages and features of the present invention may be discerned from reviewing the accompanying drawings and the detailed description of the invention. 

   
     BRIEF DESCRIPTION OF THE DRAWINGS 
     The present invention may take form in various system and method components and arrangement of system and method components. The drawings are only for purposes of illustrating an exemplary embodiment and are not to be construed as limiting the invention. 
       FIG. 1  is a block diagram of a system incorporating the principles of the present invention; 
       FIG. 2  is a block diagram of the wearable computer shown in the system of  FIG. 1 ; 
       FIG. 3  is a block diagram of computer software that may be used to implement the system and method of the present invention; and 
       FIG. 4  is a flow chart of an exemplary process that may be implemented in the network access device of the system shown in  FIG. 1 . 
   

   DETAILED DESCRIPTION OF THE INVENTION 
   A computer system incorporating the principles of the present invention is shown in  FIG. 1 . System  10  includes a personal access network (PAN) device such as a wearable computer  14 , a personal area network receiver  18 , and a server  20 . System  10  may also a computer station  24  that may be a checkout terminal or the like. Wearable computer  14  is comprised of a low power transmitter, low frequency transmitter that is powered by the human body salinity. Device  14  generates an external electric field that is transmitted by the human body brought in close proximity or contact with PAN receiver  18 . 
   Device  14  is shown in more detail in  FIG. 2 . Device  14  is powered by an internal power source  30  such as a watch battery or the like. Power source  30  is coupled to an oscillator  32  to generate an electrical potential between electrode  34  and a virtual ground electrode  38 . Virtual ground electrode  38  is held at zero potential by an operational amplifier within oscillator  32  so a current flows to ground through the oscillator electrode. As long as the area of electrodes  34  and  38  are small relative to the spacing between them, the electrodes act as point charges that produce dipole fields. The body of the person wearing device  14  cuts the electric field lines of these dipole fields, and at close proximity to electrodes  34  and  38 , the body of the person acts as a charge reservoir so the current to ground increases. A device of this type is described in an article entitled  Applying Elecric Field Sensing to Human - Computer Interfaces  by T. Zimmerman, J. Smith, J. Paradiso, D. Aliport, and N. Gershenfeld that is part of the CHI &#39;95 Proceedings Papers. That article is hereby incorporated by reference in its entirety. Such a device generates a signal having a current measured in picoamps and its frequency is less than 1 MHz. 
   A data storage unit  40  in which personal identification data and/or financial account data may be stored is also coupled to power source  30 . When a wearer activates electrical switch  42 , modulator  44  retrieves user data from storage unit  40  and modulator  44  modulates the current at electrode  34 . The modulated current is capacitively coupled to the wearer&#39;s body and a low power, low frequency signal modulated with the personal identification data is emitted by the wearer. When the wearer brings a finger or other body part into proximity or contact with PAN receiver  18 , the modulated signal may be received and demodulated to obtain the user data. 
   The low power, low frequency signal emitted from the person is not radiated at power levels sufficient for reception by eavesdropping devices unless they practically come in contact with the person. Consequently, the opportunity for signal interference and eavesdropping is significantly reduced by the device of the present invention. PAN receiver  18  may also be provided with a low power, low frequency transmitter that may be used to return data to device  14 . Preferably, receiver  18  is provided with a visual and/or audio indicator that a data message for device  14  is ready. To receive the message, the wearer again brings a finger or other body part into proximity or contact with PAN receiver  18  and the signal from the transmitter of receiver  18  is coupled to the person&#39;s body. The signal may then be detected at the ground electrode as the modulated signal at electrode  34  ceases upon release of the electrical switch activating modulator  44 . The modulations in the ground current may be demodulated and used to generate data that may be stored in storage unit  40 . In this manner, data may be transferred between PAN receiver  18  and device  14  to update financial data such as that that may be stored in a smart card or the like. 
   In system  10 , device  14  may be used to provide user data such as personal identification data or financial transaction data to a PAN receiver  18  for processing by a retail establishment computer server  20 . Server  20  may use the personal identification data to query a customer database for information about the identified customer. Server  20  may use the customer data to retrieve a promotion offer that corresponds to the customer&#39;s buying habits and other data stored in the customer database. The offer data may be presented to the customer through the display of a computer station  24  associated with PAN receiver  18 . Computer station  18  may be an application specific integrated circuit (ASIC) for displaying promotion data or it may be a checkout terminal for processing payment data. In the latter case, the personal identification data received from device  14  may include financial account data that may be used by server  20  to generate data messages for obtaining credit card transaction authorization through a payment processor. Upon receipt of the authorization code, server  20  sends an authorization message to station  24  so the transaction may be completed. Also, server  20  may send transaction data to PAN receiver  18  for transmission to device  14  if PAN receiver  18  is provided with a transmitter for communicating with device  14 . Thus, device  14  and receiver  18  may communicate in a unidirectional mode or in a bi-directional mode. 
   The software for implementing system  10  is shown in  FIG. 3 . User personal data storage  40  may be used to store a personal identification key such a preferred customer identification number or other identification codes such as a key generated from biometric data to further enhance the security of the system. Storage unit  40  may also include credit card data or other financial account data as may be stored in a smart card or the like. A select feature function (block  100 ) may be activated by a user with dedicated actuators on device  14  or through a limited function keyboard of the device. The features include personal identification, payment transaction, or other functions that may be available through server  20  of system  10 . Personal identification may be used to retrieve promotion offers or other customer incentives while payment transaction may be used to effect payment at a checkout terminal or the like. A retrieve user information function (block  104 ) queries storage unit  40  for the data that corresponds to the activated function. This data is provided to a send user information function (block  108 ) for transmission to PAN receiver  18 . 
   An exemplary process of the send user function is shown in  FIG. 4 . That process receives user information, either personal identification data or financial transaction data, (block  180 ) and modulates the current at electrode  34  with the received data (block  184 ). The method of modulation may be according to any known scheme of low power, low frequency signal modulation. Likewise, the messages containing the user information data may formatted according to any known message format used for such purposes or it may be a proprietary scheme used to communicate with a server  20 . The modulated signal is coupled to electrode  34  (block  188 ) so it may be capacitively coupled to the wearer&#39;s body for transmission. 
   Returning to  FIG. 3 , PAN receiver  18  includes a function for receiving the low power, low frequency signal emitted by the wearer&#39;s body and demodulating that signal to obtain the user information (block  110 ). This information may then be used to generate data messages for communication with server  20  (block  114 ). 
   Server  20  includes a function to receive the user data messages (block  118 ) and use the information to validate and authenticate the user (block  120 ). For example, PAN receiver may be coupled to a fingerprint imaging device that generates an image of a person&#39;s fingerprint and encodes that data for transmission to server  20 . The validate and authenticate function may then compare the biometric data received from device  14  to the fingerprint image to determine whether the wearer corresponds to the received user information. Other known validation schemes may be used such as entry of a PIN code or the like. Once validated, server  20  determines whether a payment transaction is occurring and activates the make payment function (block  124 ) in response. The make payment function uses the user data to generate the necessary data messages for communication with a payment processor. Upon receipt of an authorization code, the receive confirmation function (block  128 ) provides an authorization message to send data function (block  130 ) for server  20 . In response to the validation function determining the wearer and user data correspond but the user is not requesting a payment transaction, the data message is passed to the retrieve user data function (block  134 ) for server  20 . The retrieve user data function determines the location and/or function of PAN receiver  18 . For example, location of PAN receiver  18  at a promotion site may result in the retrieve user data function of server  20  querying database  48  to determine an activity level for the customer. This data may be used to generate a promotion offer, discount, or the like. This data may then be formatted in a data message and provided to the send data message function (block  130 ) of server  20 . This function may then send messages to PAN receiver  18  or computer station  24 . 
   Data messages for device  14  are received by the receiver function (block  138 ) of PAN receiver  18  and converted to the low power, low frequency signal levels and format for device  14  by the send data function (block  140 ). This signal is received by the wearer&#39;s body and detected at electrode  38  by receive data function (block  144 ) of device  14 . The data may be displayed at wearable device  14  by display data function (block  148 ) and/or stored in storage unit  40  by store data function (block  150 ). Likewise, data messages sent from server  20  to computer station  24  are received, processed, and displayed by functions resident in computer station  24  (block  154 ). 
   To implement system  10 , wearable computers are issued to customers with storage units  40  that contain their personal identification data and/or financial account data for credit card, smart card, or other financial token transactions. PAN receivers are then installed at promotion sites throughout a retail establishment or the like or in association with checkout or other payment terminals. The PAN receivers are programmed to communicate in data messages that comply with the network communication requirements of the network managed by server  20 . Server  20  is also provided with the functions for validating and authenticating users with data received from wearable computers. In operation, customers upon the premises of an establishing having PAN receivers may then access the network managed by server  20  by activating wearable device  14  to generate a personal identification signal or a financial transaction signal. PAN receiver  18  may then provided the personal identification or financial transaction signal in a network compatible message to server  20  for authentication and validation and other processing. Server  20  responses with appropriate data messages that may be returned to wearable computer  14  via PAN receiver  18  or to computer station  24 . In this manner, customers are able to access an establishment&#39;s computer system at network access points without significant risk of compromising personal identification or financial account data. 
   While the present invention has been illustrated by the description of an exemplary process and system components, and while the process and various components have been described in considerable detail, the applicant does not intend to restrict or in any limit the scope of the appended claims to such detail. For example, the system and method of the present invention may be used in any electronic device having a display for which brightness control is available. Additional advantages and modifications will also readily appear to those skilled in the art. The invention in its broadest aspects is therefore not limited to the specific details, implementations, or illustrative examples shown and described. Accordingly, departures may be made from such details without departing from the spirit or scope of applicant&#39;s general inventive concept.