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:
Sep. 24, 2002
Filed:
Dec. 01, 2000
Thomas G. Xydis, Ann Arbor, MI (US);
Ensure Technologies, Inc., Ann Arbor, MI (US);
Abstract
A security apparatus and a method for determining the distance between a computer ( ) and a token ( ) carried by a user ( ) for allowing the user ( ) to access the computer ( ). The computer ( ) is connected to a first transceiver ( ) having at least one antenna for emitting and detecting a radio frequency (RF) signal, and to a microphone ( ) for detecting an audio signal ( ). The computer ( ) is also connected to a counter ( ) for measuring a time interval ( ) between a transmitted RF signal ( ) and audio signal ( ) from the token ( ). The token ( ) is connected to a second transceiver ( ) having at least one antenna for emitting and detecting a RF signal ( ) and a loudspeaker ( ) for emitting an audio signal ( ). The method is characterized by comparing the measured time interval ( ) to a predetermined time range ( ) and enabling the computer ( ) in response to the time interval ( ) being within the predetermined time range ( ) such that the user ( ) may have access to the enabled computer ( ) and disabling the computer ( ) in response to the time interval ( ) being outside the predetermined time range ( ).