Method and apparatus for performing frequency spectrum inversion

Details Method and apparatus for performing frequency spectrum inversion Method and apparatus for performing frequency spectrum inversion

1996-08-02

1998-08-18

Buczinski, Stephen C.

Cryptography

Communication system using cryptography

Frequency shift or inversion

380 19, 380 39, 380 49, H04K 100, H04L 900

Patent

active

057968381

ABSTRACT:
An apparatus and method for creating voice privacy by performing frequency spectrum inversion in electronic voice transmission systems includes the steps of digitizing an analog signal and inverting the frequency spectrum of the digitized audio signal. From the inverted spectrum, a complex signal is created from which the real component is extracted to produce a real signal suitable for transmitting. The digital signal processing is performed entirely with software. The scrambling and descrambling processes are nearly identical, therefore, the same hardware and software may be used to scramble and descramble the signal. The apparatus may uses a "rolling code" to increase the effectiveness of the scrambling.

REFERENCES:
patent: 3777964 (1973-12-01), Allen et al.
patent: 4908860 (1990-03-01), Capparese et al.
patent: 5159631 (1992-10-01), Quan et al.
patent: 5278907 (1994-01-01), Snyder et al.
patent: 5471531 (1995-11-01), Quan

Affiliated with

Also associated with

Rating

Method and apparatus for performing frequency spectrum inversion does not yet have a rating. At this time, there are no reviews or comments for this patent.

If you have personal experience with Method and apparatus for performing frequency spectrum inversion, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Method and apparatus for performing frequency spectrum inversion will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFUS-PAI-O-1123042