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Showing 1 to 17 of 17 for “"Free-Space Optical Communications"”.
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Sensorless Wavefront Correction Algorithms for Free-Space Optical Communications
Free-space optical communications (FSOC) technology facilitates high-throughput wireless links across large distances with low size, weight, and power (SWaP) terminals. However, it is difficult to design reliable, low-cost FSOC terminals for long-range links through the atmosphere. Even in clear …
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Tracking algorithms under boundary layer effects for free-space optical communications
Free-space optical communication requires accurate tracking to maintain links. The tracking problem between an aircraft and satellite becomes more difficult with the introduction of a turret on the aircraft for increased field-of-regard. In the case of a hemispherical turret, the disrupted airflow …
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Strategies for limiting interference and interception of free space optical communications
Free space optical systems provide an attractive solution to communication needs that require inexpensive, easily deployable links capable of high data rate transmissions. A major challenge of free space optical communication is ensuring the integrity and confidentiality of the transmitted …
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Reciprocity-enhanced time-division multiplexed optical switching with spatial diversity for free-space optical communication links
… analysis and experimental measurements of a free-space optical communications system that exploits optical reciprocity to switch between multiple (N) spatially-diverse apertures to increase data transmission through a scintillating channel. Electromagnetic signals, specifically optical, …
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NIR silicon photodetector enhancement using photonic crystal cavity resonators
… for light ranging, thermal-cameras, and soon, free-space optical communications has yet to be answered. In this study, we use polycrystalline silicon in conjunction with a photonic crystal cavity (PhCC) to enhance light absorption for efficient sensing. We present a cost-effective alternative …
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Precision Pointing for the CubeSat Laser Infrared CrosslinK (CLICK) Mission
Advances in Free Space Optical Communications have led to numerous missions that have demonstrated optical space-to-ground links, however, fewer missions have demonstrated optical space-to-space links. NASA’s CubeSat Laser Infrared CrosslinK (CLICK) Mission aims to be the first to demonstrate …
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Dynamic pixel selection in free-space photon-counting optical communication systems for the exploitation of excess channel capacity
Atmospheric turbulence in free-space optical communications turns signal demodulation and decoding into a multimode problem as wavefronts of the transmitting laser beams are warped spatially past the desired form of a diffraction-limited spot at the receiver end of a free-space optical receiver. …
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Small satellite optical communication receiver for simultaneous spatial tracking and data demodulation
Free-space optical communications in space offer many benefits over established radio frequency based communication links; in particular, high beam directivity results in efficient power usage. Such a reduced power requirement is particularly appealing to small satellites with strict size, weight …
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Spatially-Adaptive LiDAR and Underwater Communications Using Integrated Optical Phased Arrays
… communication systems. In particular, integrated optical-phased-array-based (OPA-based) technologies, such as solid-state LiDAR and free-space optical communications (FSOC) systems, show promise to revolutionize the way we sense and communicate. This thesis enables new integrated-OPA-based …
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Superconducting nanowire single-photon detectors and sub-10-nm lithography
… (SNSPDs) are useful in applications such as free-space optical communications to achieve high-speed data transfer across vast distances with minimum transmission power. In this and other applications, SNSPDs with high detection efficiencies are required. To this end, we designed and …
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Systems Performance Analysis for Autonomous Spacecraft Navigation within Satellite Constellations using Intersatellite Optical Communications Links
Free-space optical communications is an advanced technology for high data rate communications that has experienced rapid development for space applications over the last couple decades, due to the increasing need for bandwidth with modern sensing and information technologies. Lasercom has …
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Silicon Photomultipliers as Free Space Optical Communication Sensors
Free-space optical communications (FSOC) is a growing field that presents an attractive alternative to the the current technology standard of radio frequency (RF) communications. Typical optical carriers have smaller SWaP in comparison to RF systems due to the difference in required aperture sizes. …
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Multiple Simultaneous Optical Links for Space-Based Platforms
Space-based Free Space Optical Communications (FSOC), or lasercom, offers key advantages over Radio Frequency (RF) communications in bandwidth, Size, Weight, and Power savings, and unregulated spectrum. Theoretical and demonstrated lasercom systems have shown higher data rates for similar or equal …
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Optical Performance and Prototyping of a Liquid Lens Laser Communications Transceiver
Laser communications can enable more efficient and higher bandwidth communications than conventional radio frequency (RF) systems. Free-space optical communications systems' beams are typically narrower in divergence and require precise pointing, acquisition, and tracking (PAT) systems to establish …
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Low-Cost Spatial Light Modulator for Applications in Free-Space Optical Communication
… distortions. AO is an enabling technology for Free-Space Optical Communication, whose performance is severely degraded by the atmosphere. This thesis proposes two low-cost AO strategies: (1) repurposing Liquid Crystal (LC) SLM from an old display projector and (2) sensorless correction enabled …