Science Daily November 9, 2022 While enabling orders-of-magnitude gains in data rates, optical signals impose much stricter pointing requirements and are strongly affected by atmospheric turbulence. Researchers in Australia established a coherent 1550 nm link across turbulent atmosphere between a deployable optical terminal and a drone-mounted retroreflector. Through 10 Hz machine vision optical tracking with nested 200 Hz tip/tilt adaptive optics stabilisation, they corrected for pointing errors and atmospheric turbulence to maintain robust single mode fiber coupling, resulting in an uninterrupted 100 Gbps optical data link while tracking at angular rates of up to 1.5 deg/s, equivalent to that of […]
Tag Archives: Free space communications
Unipolar quantum optoelectronic devices: Higher speeds in free-space optical communications in the midinfrared band
Phys.org November 2, 2022 A recently demonstrated proof-of-concept of high-speed transmission taking advantage of intersubband devices was limited by the short-distance optical path (up to 1 m). An international team of researchers (France, USA -University of Central Florida, University of New Mexico) used an uncooled quantum cascade detector and a nitrogen-cooled quantum well-infrared photodetector to study the possibility of building a long-range link using unipolar quantum optoelectronics. They evaluated the maximum data rate of their link in a back-to-back configuration before adding a Herriott cell to increase the length of the light path up to 31m. By using pulse shaping, […]