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US5805635A Expired / Lapsed US ⏱️ 0.0 years remaining

Secure communication system

Assignee: United States Department of the Navy
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Filing: 1964-03-17
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Granted: 1998-09-08
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Expires: 1984-03-17
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Abstract

Abstract A secure communication system comprising: a first cyclical pseudo-random noise generator comprising determinable vable starting point means and an output; transmitting means for transmitting said pseudo-random noise generator output; receiving means for receiving said transmitting means transmissions, said receiving means having an output; recycling storage means for storing said receiving means output; a second cyclical pseudo-random noise generator identical to said first pseudo-random noise generator having an output and a reset input, said receiving means output connected to said reset input; a correlator having a first input connected to said storage means and a second input connected to said second pseudo-random noise generator output and an output from said correlator; and timing means connected to said receiving means output and said correlator output for measuring time elapsed between any output of said receiver and said correlator.

Inventors

  • 👤 Daniel E. Andrews, Jr.
  • 👤 William E. Klund
  • 👤 Robert D. Isaak

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-11-09 17:56
CPC Classifications
H; H04; H04B; H04B1/00; H04B1/69; H04B1/707; H04B1/7073; H04B1/7075; H04B1/709; H04K; H04K1/00; H04B2201/00; H04B2201/69; H04B2201/707; H04B2201/70715

Claims Analysis

Total Claims: 7
Claim 1
Independent Claim 137 words
A secure communication system comprising: a first cyclical pseudo-random noise generator comprising determinable variable starting point means and an output; transmitting means for transmitting said pseudo-random noise generator output; receiving means for receiving said transmitting means transmissions, said receiving means having an output; recycling storage means for storing said receiving means output; a second cyclical pseudo-random noise generator identical to said first pseudo-random noise generator having an output and a reset input, said receiving means output connected to said reset input; a correlator having a first input connected to said storage means and a second input connected to said second pseudo-random noise generator output and an output from said correlator; and is timing means connected to said receiving means output and said correlator output for measuring time elapsed between any output of said receiver and said correlator.
Claim 2
Dependent Claim 137 words
A secure communication system comprising: a first cyclical pseudo-random noise generator comprising determinable variable starting point means and an output; transmitting means for transmitting said pseudo-random noise generator output; receiving means for receiving said transmitting means transmissions, said receiving means having an output; recycling storage means for storing said receiving means output; a second cyclical pseudo-random noise generator identical to said first pseudo-random noise generator having an output and a reset input, said receiving means output connected to said reset input; a correlator having a first input connected to said storage means and a second input connected to said second pseudo-random noise generator output and an output from said correlator; and is timing means connected to said receiving means output and said correlator output for measuring time elapsed between any output of said receiver and said correlator.
Claim 3
Dependent Claim 14 words
The secure communication system of claim 1 wherein said storage means comprises a deltic.
Claim 4
Dependent Claim 17 words
The secure communication system of claim 1 wherein said storage means comprises an incremental recirculating delay line.
Claim 5
Dependent Claim 29 words
The secure communication system of claim 1 further comprising a threshold detector coupled between said receiver output and said storage for triggering the start of storage of received signals.
Claim 6
Dependent Claim 30 words
The secure communication system of claim 1 and further including means for determining said variable starting point of said first pseudo-random noise generator connected to said first pseudo-random noise generator.
Claim 7
Dependent Claim 54 words
The secure communication system of claim 1 wherein said timing means comprises: a counter having a start input, a stop input, and a clock pulse input; said start input connected to said receiving means output; said stop input connected to said correlator output; and a clock pulse generator connected to said clock pulse input.

References Cited (Backward Citations)

US2929865A Cited
US3099796A Cited
US3157874A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 2001-09-07 2002-03-09 2002-09-08 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 2005-09-07 2006-03-09 2006-09-08 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 2009-09-07 2010-03-09 2010-09-08 $7700.00 Window Closed / Lapsed

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