Secure communications with low-orbit spacecraft using quantum cryptography

Patent · Fri Jan 01 00:00:00 EST 1999

OSTI ID:872585

Hughes, Richard J ^[1]; Buttler, William T ^[1]; Kwiat, Paul G ^[1]; Luther, Gabriel G ^[1]; Morgan, George L ^[2]; Nordholt, Jane E ^[1]; Peterson, Charles G ^[1]; Simmons, Charles M ^[1]

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1. Los Alamos, NM
2. Jemez Springs, NM

Apparatus and method for secure communication between an earth station and spacecraft. A laser outputs single pulses that are split into preceding bright pulses and delayed attenuated pulses, and polarized. A Pockels cell changes the polarization of the polarized delayed attenuated pulses according to a string of random numbers, a first polarization representing a "1," and a second polarization representing a "0." At the receiving station, a beamsplitter randomly directs the preceding bright pulses and the polarized delayed attenuated pulses onto longer and shorter paths, both terminating in a beamsplitter which directs the preceding bright pulses and a first portion of the polarized delayed attenuated pulses to a first detector, and a second portion of the polarized delayed attenuated pulses to a second detector to generate a key for secure communication between the earth station and the spacecraft.

• Research Organization: Los Alamos National Laboratory (LANL), Los Alamos, NM (United States)
• DOE Contract Number: W-7405-ENG-36
• Assignee: Regents of University of California (Los Alamos, NM)
• Patent Number(s): US 5966224
• OSTI ID: 872585
• Country of Publication: United States
• Language: English

Related Subjects

secure
communications
low-orbit
spacecraft
quantum
cryptography
apparatus
method
communication
earth
station
laser
outputs
single
pulses
split
preceding
bright
delayed
attenuated
polarized
pockels
cell
changes
polarization
according
string
random
representing
receiving
beamsplitter
randomly
directs
shorter
paths
terminating
portion
detector
generate
key
laser output
pockels cell
single pulse
receiving station
secure communication
orbit space
laser outputs
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