Portable biometric authentication device and terminal device using near field communication

Abstract

A portable biometric authentication device communicates with a terminal device using near field communication (NFC). The portable biometric authentication device includes; a NFC antenna, a power supply circuit that generates at least one power voltage in response to an electromagnetic field generated by the terminal device and received via the NFC antenna, a sensor subsystem that operates in response to the at least one power voltage and includes a biometric sensor that acquires biometric information from a user, and a control subsystem that operates in response to the at least one power voltage and includes a NFC controller that controls the communication of the biometric information to the terminal device using the NFC antenna.

What is claimed is: 
     
         1 . A portable biometric authentication device that communicates with a terminal device using near field communication (NFC), the portable biometric authentication device comprising:
 a NFC antenna;   a power supply circuit that generates at least one power voltage in response to an electromagnetic field generated by the terminal device and received via the NFC antenna;   a sensor subsystem that operates in response to the at least one power voltage and includes a biometric sensor that acquires biometric information from a user; and   a control subsystem that operates in response to the at least one power voltage and includes a NFC controller that controls the communication of the biometric information to the terminal device using the NFC antenna.   
     
     
         2 . The portable biometric authentication device of  claim 1 , wherein the at least one power voltage includes a first power voltage provided to the sensor subsystem and a second power voltage, different from the first power voltage, provided to the control subsystem. 
     
     
         3 . The portable biometric authentication device of  claim 1 , wherein the biometric sensor comprises a fingerprint sensor that acquires a fingerprint image from the user and generates the biometric information from the fingerprint image. 
     
     
         4 . The portable biometric authentication device of  claim 3 , wherein the sensor subsystem further comprises a biometric information compressing unit that compresses the fingerprint image to generate the biometric information. 
     
     
         5 . The portable biometric authentication device of  claim 3 , wherein the control subsystem comprises an encryption processing unit that encrypts the biometric information before the biometric information is communicated to the terminal device. 
     
     
         6 . The portable biometric authentication device of  claim 5 , wherein the portable biometric authentication device is implemented in a mobile phone case having a first surface configured to receive a mobile phone and an opposing second surface externally exposing the fingerprint sensor and NFC antenna. 
     
     
         7 . The portable biometric authentication device of  claim 1 , further comprising:
 an inductor that generates a magnetic flux external to the portable biometric authentication device,   wherein the NFC controller controls the communication of magnetic stripe data received from the terminal device, and   the control subsystem further comprises an inductor driver that drives the inductor based on the magnetic stripe data in such a manner that the inductor generates a magnetic pulse.