Method and system for compensating for signal deviations in tone signals over a transmission channel

• US 5,949,874 A
• Filed: 11/25/1997
• Issued: 09/07/1999
• Est. Priority Date: 08/05/1994
• Status: Expired due to Fees

• Current Assignee: Smart Tone Incorporated
• Original Assignee: Smart Tone Authentication, Inc.
• Inventors: Mark, Andrew R.
• Primary Examiner(s): Wolinsky, Scott
• Application Number:
  US08/978,395
• Time in Patent Office: 651 Days
• Field of Search: 379/361, 379/282, 379/283, 379/286, 379/257, 379/93.26, 379/91.01, 379/93.01, 379/93.02, 379/93.03, 379/67, 379/88, 379/89, 379/188, 379/189, 379/386, 379/351 , 379/88.02, 704/243, 704/244
• US Class Current: 379/283
• CPC Class Codes: G06Q 20/341 Active cards, i.e. cards including their own processing means, e.g. including an IC or chip
• CPC Class Codes: G06Q 20/346 Cards serving only as information carrier of service
• CPC Class Codes: G07F 7/0886 the card reader being portable for interacting with a POS or ECR in realizing a payment transaction
• CPC Class Codes: G07F 7/1008 Active credit-cards provided with means to personalise their use, e.g. with PIN-introduction/comparison system
• CPC Class Codes: G10L 17/00 Speaker identification or verification techniques
• CPC Class Codes: H04M 1/271 controlled by voice recognition
• CPC Class Codes: H04M 1/275 implemented by means of portable electronic directories
• CPC Class Codes: H04M 1/2757 by data transmission, e.g. downloading
• CPC Class Codes: H04M 1/50 by generating or selecting currents of predetermined frequencies or combinations of frequencies
• CPC Class Codes: H04M 1/66 with means for preventing unauthorised or fraudulent calling verifying user identity or authority in secret or secure digital communications H04L9/32
• CPC Class Codes: H04M 1/67 by electronic means
• CPC Class Codes: H04M 15/00 Arrangements for metering, time-control or time indication ; Metering, charging or billing arrangements for voice wireline or wireless communications, e.g. VoIP
• CPC Class Codes: H04M 17/00 Prepayment of wireline communication systems, wireless communication systems or telephone systems using a coded card to authorise calls from a telephone set H04M1/675
• CPC Class Codes: H04M 17/02 Coin-freed or check-freed systems , e.g. mobile- or card-operated phones, public telephones or booths
• CPC Class Codes: H04M 2201/40 using speech recognition speech recognition per se G10L15/00
• CPC Class Codes: H04M 3/16 with lock-out or secrecy provision in party-line systems
• CPC Class Codes: H04M 3/382 using authorisation codes or passwords
• CPC Class Codes: H04M 3/44 Additional connecting arrangements for providing access to frequently-wanted subscribers, e.g. abbreviated dialling at the subscriber's set H04M1/27; automatic redialling H04M3/424
• CPC Class Codes: H04M 3/493 Interactive information services, e.g. directory enquiries ; Arrangements therefor, e.g. interactive voice response [IVR] systems or voice portals
• CPC Class Codes: H04Q 1/453 in which m-out-of-n signalling frequencies are transmitted

Abstract

A user-authentication system includes an authorized user device (AUD) for transmission of DTMF tones to a user-verification system (UVS) over a telephone network, where user-verification is performed and authorized users are granted access to a desired service. In a memory module of the AUD, a plurality of passphrases and identifying data are stored for subsequent transmission to the UVS. The UVS includes a memory module for receiving and storing the passphrases and identifying data, and a processor for determining whether user-stated passphrases correspond to the stored passphrases, and for prompting the user with knowledge-based questions and determining whether the identifying data corresponds to answers given by a user in response to the knowledge-based questions. The UVS further includes security safeguards such as a transmitter transmitting a signal relating to time while a user is stating a passphrase, to determine whether a user-stated passphrase comprises a previously recorded passphrase, and an analyzer device determining whether the access number used to reach the user-verification system is appropriate for the specific user-device.

Claims

1. A system for performing signal normalization over a channel comprising:

a controller generating a first plurality of tones and a second plurality of tones, said first plurality of tones representative of at least a portion of a frequency range of a user'"'"'s voice;

a transmitter in electrical communication with said controller transmitting said first plurality of tones and said second plurality of tones over a telephone network to a processor;

said processor comprising;

a memory module storing predetermined tone signals therein;

a receiver receiving said first plurality of tones;

a comparing module coupled to said receiver and said memory module, comparing said first plurality of tones to said predetermined tone signals;

a compensating module coupled to said comparing module to compensate for signal deviations in said first plurality of tones; and

a correcting module coupled to said compensating module correcting said second plurality of tones in response to said compensating module.

2. The system according to claim 1, wherein said second plurality of tones represent user-stated information.

3. The system according to claim 2, said processor further comprising:

a transmitter prompting a user to speak a passphrase into a microphone;

wherein said receiver receives said passphrase spoken by the user and said correcting module corrects signal deviations in said spoken passphrase, said signal deviations including amplitude deviations.

4. The system according to claim 3, said processor further comprising a second comparing module comparing tones representing said corrected spoken passphrase with said corrected second plurality of tones to determine if the user is authorized.

5. A method for performing signal normalization over a channel comprising:

generating a first plurality of tones representative of at least a portion of a frequency range of a user'"'"'s voice;

transmitting said first plurality of tones over a telephone network to a controller;

comparing said first plurality of tones to predetermined tones stored in a memory module coupled to said controller;

generating compensating factors corresponding to said first plurality of tones to compensate for signal deviations in said first plurality of tones;

transmitting a second plurality of tones to said controller; and

correcting signal deviations for each of said second plurality of tones using said compensating factors.

6. The method according to claim 5, wherein said second plurality of tones represent user-stated information.

7. The method according to claim 6, further comprising:

prompting a user to speak a passphrase into a microphone in communication with said controller;

receiving said spoken passphrase; and

correcting deviations in said spoken passphrase using said compensating factors, wherein said compensation factors comprise amplification factors.

8. The method according to claim 7, further comprising:

comparing tones representing said corrected spoken passphrase with said corrected second plurality of tones to determine if the user is authorized.