Pulse or digital communications – Repeaters – Testing
Patent
1968-01-24
1982-11-30
Birmiel, Howard A.
Pulse or digital communications
Repeaters
Testing
375 21, 455 30, 179 15S, H04K 102
Patent
active
043617298
ABSTRACT:
A privacy system in which an analog information-bearing signal is linearly combined with a noiselike coding waveform to produce a composite waveform of unrecognizable, scrambled signal for transmission to an authorized system user at a remote receiving terminal. The noiselike waveform is developed from the original information signal, and the original signal reproduced from the composite waveform, to eliminate any need for synchronization between transmitter and receiver. At the transmitting terminal, the composite waveform is infinitely clipped and amplified to produce a digital format which is serially fed through a shift register in accordance with shift pulses derived from the clipped signal transitions. Various outputs of the several stages of the shift register are selectively applied, via a switching matrix, to an encoder which generates the noiselike or pseudo-random signal therefrom. After passage through a narrowband filter, the coding waveform is added in a linear mixer to the original information signal for transmission. An inverse operation is performed at the receiving terminal.
REFERENCES:
patent: 2406841 (1946-09-01), Levy
patent: 2543116 (1951-02-01), Llewellyn
patent: 2777897 (1957-01-01), Gretener et al.
patent: 2947804 (1960-08-01), Eilers et al.
patent: 2953643 (1960-09-01), Koenig, Jr.
patent: 3012099 (1961-12-01), Busch et al.
patent: 3025350 (1962-03-01), Lindner
patent: 3029309 (1962-04-01), Van Jepmond
patent: 3077518 (1963-02-01), Guanella
patent: 3123672 (1964-03-01), Ross
patent: 3133991 (1964-05-01), Guanella
patent: 3225142 (1965-12-01), Schroeder
patent: 3515805 (1970-06-01), Fracassi et al.
OSRD Report No. 3802, dated Nov. 1, 1944, for "Articulation Testing Methods II", J. P. Egan, Psycho-Acoustic Laboratory, Harvard University, Cambridge, Mass.
"Linear Recurring Sequences", Zierler, Journal of the Society of Industrial and Applied Mathematics, pp. 31-48, Mar. 1959.
"Some Simple Self-Synchronizing Digital Data Scramblers", Savage, Bell System Technical Journal, Feb. 67, vol. 46, No. 2, pp. 449-487.
Barnes, Jr. Laurence A.
Irons Ronald E.
American Standard Inc.
Birmiel Howard A.
Crooks Robert G.
Salerno, Jr. James J.
Sinnott John P.
LandOfFree
Narrowband analog message privacy system does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Narrowband analog message privacy system, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Narrowband analog message privacy system will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-196778