Patent ID: 7949535
Filing Date: 2011-05-24
Classification: G06F

Abstract:
1. A user authentication system for performing user authentication using voice authentication technology, the user authentication being performed during a first period before a user utters and a second period in which the user utters, the system comprising: a sound pick-up portion for picking up ambient sound around the user during the first period and the second period; an intensity level calculation portion for calculating an intensity level of the ambient sound picked up during the first period for each of a plurality of sections into which the first period is divided; and a fraudulent user determination portion that defines one of the plurality of sections of the first period as a reference section, selects a section in the first period sequentially starting from a section temporally subsequent to the reference section, compares the selected section with the reference section, determines that the user is a fraudulent user who attempts to obtain authentication by reproducing voice with a reproducer if the intensity level for the selected section is larger than the intensity level for the reference section and, at the same time, a difference between the intensity levels for the selected section and the reference section is equal to or larger than a predetermined value.