The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
May. 09, 1995
Filed:
Aug. 10, 1994
Lawrence G Bahler, San Diego, CA (US);
Alan L Higgins, San Diego, CA (US);
ITT Corporation, New York, NY (US);
Abstract
A telephone long distance service is provided using speaker verification to determine whether a user is a valid user or an impostor. The user claims an identity by offering some form of identification, typically by entering a calling card number on the phone's touch-tone keypad or by a magnetic strip on the card which is read by the telephone. Unrestricted, extemporaneous speech of a group of customers are digitized, analyzed in accordance with a PCM circuit, and characterized as a non-parametric set of speech feature vectors. The extemporaneous speech of the long distance telephone service user claiming the identity of a service customer via his card number is digitized and analyzed in a like manner. The identity of the user is verified by comparing, either during or after the call, the signals in accordance with an algorithm which compares a reference utterance of a known customer with input utterances from one or more unknown telephone service users, one of which users has claimed the identity of the customer. This comparison results in a decision to accept or reject the hypothesized identity. The identity hypothesis to be tested is thus derived from the calling card of the customer.