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.

Date of Patent:
Feb. 12, 1980

Filed:

May. 20, 1976
Applicant:
Inventors:

Pierre Schmid, Oberweningen, CH;

Eduard Brunner, Oberengstringen, CH;

Walter Stofer, Buchs, CH;

Assignee:

Gretag Aktiengesellschaft, Regensdorf, CH;

Attorney:
Primary Examiner:
Int. Cl.
CPC ...
H04K / ; H04K / ;
U.S. Cl.
CPC ...
179 / ; 179 / ;
Abstract

A method and an installation for masked or scrambled speech transmission utilize a time-scrambling unit for dividing the speech band into at least two sub-bands, for delaying the one sub-band with respect to the other, and for forming an aggregate signal, and a frequency-scrambling unit for dividing the aggregate signal into at least two second sub-bands of variable band-width, for their cyclic interchanging, and for forming a transmission signal capable of being transmitted over a transmission channel, in order to mask not only the sound character of the speech signals but also the speech rhythm, thus ensuring increased privacy of transmission with high code-changing speed and low sensitivity to distortion.


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