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:
Jul. 28, 1998
Filed:
Mar. 24, 1997
Christopher A Hall, Lancaster County, NE (US);
James R Holthaus, Douglas County, NE (US);
Bradley A Riensche, Lancaster County, NE (US);
Transcrypt International, Inc., Lincoln, NE (US);
Abstract
An apparatus and method for voice privacy for cellular phones includes generic connection points to make it universal for most cellular phones. The connection points include the speaker and microphone and the microphone input and speaker output of the cellular phone. A scrambling or encryption circuit or process is used to secure the audio before it is transmitted over the network, and the unsecured audio once received. Side-tone added by the cellular phone and network echo of the scrambled audio to be transmitted is removed by, for example, adaptive echo cancellation, and unscrambled side-tone is presented to the speaker. The apparatus can be implemented in a digital signal processor.