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LPI in pulsed laser space communications
IEEE Journal on Selected Areas in Communications, 1993A basic low-probability of intercept (LPI) study for a pulsed-laser pulse position modulated (PPM) optical link with a colocated direct detection intercepting receiver is presented. The latter is considered to be a form of optical radiometer using continuous threshold testing to detect the presence of the transmitting laser.
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Free-space laser ranging and data communication
2009 6th Workshop on Positioning, Navigation and Communication, 2009Ranging measurements in the radio band have been extensively used in space-based applications, for example in GNSS for navigation and GRACE for mapping the Earth's gravity field. However, the increasing demand in high-bandwidth communication and precision ranging will make optical systems ideal for these applications.
Juan Jose Esteban +4 more
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Laser beam combiner: applications to space-borne laser communications
Applied Optics, 1982An attractive source for spaceborne laser communications is the directly modulated single-mode GaAs/GaAlAs injection laser. GaAlAs lasers, however, show low power per diode and wide beam divergence. A simple optical concept for a laser beam combiner overcomes diode laser limitations: an array of closely packed parallel collimated laser beams can be ...
R F, Begley, D, Goux, D W, Chen, O, Giat
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Resonant laser receiver for free-space laser communications
SPIE Proceedings, 1992ABSTRACT Our approach to high receiver sensitivity is based on the optical field retaining its temporalform (and its coherence properties) despite attenuation on long-distance propagation. A field whose power corresponds to infrequent photon arrivals, if resonant with a high-finesseetalon, sees the full 100-percent transmittance, consistent with ...
Robert J. Smith +2 more
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Implementation of a Free Space Laser Communicator
2018 4th International Conference on Electrical Engineering and Information & Communication Technology (iCEEiCT), 2018Any free space laser communicator has to face the issue of attenuation over an air channel as the distance gets larger. By using FSK (frequency shift keying) we can improve that situation. FSK modulation scheme is inherently more resistant to noise than OOK (On Off Keying) which is currently used in optical communication.
M. Rashid Alam +3 more
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Space communication and radar with lasers
SPIE Proceedings, 2005Sensitive heterodyne detection with lasers applied .to radar and satellite communication is seriously hampered by the large electronic bandwidth due to random Doppler shift and frequency instability. These drawbacks can be circumvented by dual signal heterodyne detection.
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Holographic Optics For Space Laser Communications
SPIE Proceedings, 1988In this paper we examine the utility of holographic optics for their use as collection, pointing and filtering elements in a space-based optical communications system architecture. In the first section, we examine the possible applications and requirements for satellite lasercom pointing, acquisition and tracking subsystems.
James H. East, John D. Oetting
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A base laser terminal for space communication
3rd International Conference on Satellite Communications (IEEE Cat. No.98TH8392), 2002The Scientific-Industrial Corporation on Space Instruments is carrying out research and design activities for the purpose of creating a base laser terminal with capacity up to 2 Gbit/s that will be able to meet the various requirements of LEO spacecraft and satellite systems.
V. Grigoriev +5 more
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Space station laser communication transceiver
SPIE Proceedings, 1991NASA/Goddard Space Flight Center (GSFC) has initiated the development of experimental optical communication system which will be installed on Space Station Freedom. This system is part of the Space Station Attached a Payloads Program and is currently scheduled for a 1997 launch.
Michael W. Fitzmaurice +1 more
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