NASA's First Two-Way End-to-End Laser Communications System

NASA is demonstrating laser communications on multiple missions -- showcasing the benefits infrared light can have for science and exploration missions transmitting terabytes of important data. NASA: The International Space Station is getting a "flashy" technology demonstration this November. The ILLUMA-T (Integrated Laser Communications Relay Demonstration Low Earth Orbit User Modem and Amplifier Terminal) payload is launching to the International Space Station to demonstrate how missions in low Earth orbit can benefit from laser communications. Laser communications uses invisible infrared light to send and receive information at higher data rates, providing spacecraft with the capability to send more data back to Earth in a single transmission and expediting discoveries for researchers.

Managed by NASA's Space Communications and Navigation (SCaN) program, ILLUMA-T is completing NASA's first bi-directional, end-to-end laser communications relay by working with the agency's LCRD (Laser Communications Relay Demonstration). LCRD launched in December 2021 and is currently demonstrating the benefits of laser communications from geosynchronous orbit by transmitting data between two ground stations on Earth in a series of experiments. Some of LCRD's experiments include studying atmospheric impact on laser signals, confirming LCRD's ability to work with multiple users, testing network capabilities like delay/disruption tolerant networking (DTN) over laser links, and investigating improved navigation capabilities.

Easy peasy

[Fons_de_spons]

Made a wireless gigabit interface that easily can reach mars years ago. Bit error rate is high but manageable. Half of the bits transmitted are received correct.

Re:

[joe_frisch]

What frequency, how large were the dishes, and what transmit power did you need? The transmit beam width scales as wavelenth/dish_diameter so getting enough power on the receiving dish requires a large transmit power * large transmit dish / wavelength. If you go to short wavelength (light) you can greatly reduce the size and / or power of the transmitter.

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[Fons_de_spons]

Frequency does not matter for this tech. No dish needed. Depending on the bitrate, I'd estimate 5 Watt for full speed communication. For lower bitrates, i e. a few mbits it would consume a few milliwats.

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[joe_frisch]

How? You need to get power from the transmitter to the receiver. The angular width of the transmitter beam depends on the transmitting antenna size / wavelength. (diffraction limit), no way around that. The receiver area / beam area tells you how much of that power is received. So for a constant receiver and transmitter antenna (or dish ) size, the the received power drops as 1/r^2. R for interplanetary is very big, so you quickly run out of signal to noise even for a cryogenic receiver. (the effecti

Re:

[Fons_de_spons]

Yup... it is a white noise generator. It is confusing though that even then, half of the bits are correct.

Dad jokes

[RobinH]

"The International Space Station is getting a flashy technology demonstration this November."

I'm 100% in favor of the dad jokes... please keep 'em coming slashdot!

Re:

[Tim the Gecko]

Who is making the claims about faster, less sensitive, etc.? I don't see those in the nasa.gov article.

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[Shag]

Pointing is tricky, yes, but NASA and Lincoln Laboratory were doing 622Mbps lasercom to Earth from a craft orbiting the Moon... a decade ago. And have done a bunch of other things since. This article is by no means comprehensive.

But please, do go on about SpaceX being ahead. /LLab rat, but not of the LLaser-building variety.

Flashy? I thought everyone moved to HTML5 and svg?

[youn]

I thought flash/flashy communications were disabled due to security issues?

Yeah, there was a movie about this

[ItsJustAPseudonym]

There was a movie about this titled "Real Genius [wikipedia.org]. We know what's really going on. /s

Infrared light communication eh?

[Rosco P. Coltrane]

Next up: a giant Chinese TV-B-Gone sattelite to dazzle and confuse US satellites.