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:
Jun. 26, 1990
Filed:
May. 01, 1989
Kaspar A Kasparian, Raleigh, NC (US);
John D Ide, Raleigh, NC (US);
Teletec Corporation, Raleigh, NC (US);
Abstract
A method for scrambling speech such as in a mobile land based communication system is disclosed. Essentially, variable length time samples of digitized speech are stored and time inversion scrambled. The scrambled speech is converted back to analog form and transmitted to a receiver which reciprocates the process to reproduce the desired speech signals. Scrambling and descrambling of the speech signal is synchronized to provide corresponding sample time inversions and accurate reproduction of the speech input signal. The level of security afforded by the scrambling method may be varied by varying the length of the sampling period or by mixing forward and reverse time samples under control of an algorithm.