The LCRD payload is hosted 

onboard the U.S. Department 

of Defense’s Space Test 

Program Satellite 6 

(STPSat-6).

LCRD is poised to revolutionize the 

way NASA communicates with 

spacecraft by showcasing the unique 

capabilities of laser communications. 

Currently, NASA missions use radio 

frequency communications to send 

data to and from spacecraft. Radio 

waves have been used in space 

communications since the beginning 

of space exploration and have a 

proven track record of success. 

However, as space missions generate 

and collect more data, the need for 

enhanced communications 

capabilities becomes paramount.

Laser communications is one of these 

enhancements. Using lasers to 

encode and transmit data can provide 

missions with data rates 10 to 100 

times better than current radio 

systems. This advanced data transfer 

capability will allow the aerospace 

community to communicate more 

high-denition videos and photos from 

space than ever before. 

THE TECHNOLOGY

Laser communications uses a different 

wavelength of light than radio waves, 

which is how the benets of laser 

technology are realized. Laser, which 

uses invisible infrared light, has a 

shorter wavelength than radio waves. 

This allows it to transmit more data at a 

time, enabling scientists to get their 

data back from space more quickly. It 

would take roughly nine weeks to 

transmit a completed map of Mars 

back to Earth with current radio 

frequency systems. With lasers, we can 

accelerate that to about nine days. 

INFRARED VS. RADIO

LCRD

LASER COMMUNICATIONS RELAY DEMONSTRATION

National Aeronautics and 

Space Administration

NASA’S NEXT STEP IN 

OPTICAL COMMUNICATIONS
LCRD is hosted onboard the U.S. Department of Defense’s 

Space Test Program Satellite 6 (STPSat-6) and will reside in 

geosynchronous orbit, about 22,000 miles from Earth’s 

surface, to support missions in low-Earth orbit. Prior to 

mission support, LCRD will test its capabilities with 

experiments developed by NASA, other government 

agencies, industry, and academia. These experiments will 

test laser communications functionality, demonstrating how 

it can meet the aerospace industry’s growing need for 

higher data rates.

Missions in space will 

send their data to 

LCRD, which will then 

relay the information 

down to designated 

ground stations on 

Earth. LCRD’s ground 

stations are located 

high in the mountains 

of California and 

Hawaii, which were chosen for their minimal cloud coverage. Unlike radio waves, laser 

signals cannot penetrate cloud coverage so NASA must build a system exible enough to 

avoid weather interruptions. LCRD will test different cloud coverage scenarios, gathering 

valuable information about the exibility of laser communications.

LCRD will pave the way for future laser communications missions. 

The relay’s rst user will be the Integrated LCRD Low-Earth Orbit 

User Modem and Amplier Terminal (ILLUMA-T) on the International 

Space Station. ILLUMA-T will send data to LCRD at rates of 1.2 

gigabits per second over laser links, allowing for more 

high-resolution experiment data to be transmitted back to Earth.

Laser communications systems are ideal for missions like the space 

station not only because of their increased data capabilities, but also 

because laser systems provide decreased size, weight, and power 

requirements. A smaller size means more room for science 

instruments. Less weight means a less expensive launch. Less 

power means less drain on the spacecraft’s batteries. 

LCRD will demonstrate the vast advantages of laser communications 

near-Earth. This will prove that laser systems are an option for our 

future expeditions back to the Moon and then on to Mars!

National Aeronautics and Space Administration

Goddard Space Flight Center

8800 Greenbelt Road

Greenbelt, MD 20771

www.nasa.gov/goddard

www.nasa.gov

NP-2019-07-2748-HQ

Want to learn more about LCRD?

nasa.gov/lasercomms

FS-2021-4-658-GSFC

twitter.com/NASALaserComm

LCRD

LASER COMMUNICATIONS RELAY DEMONSTRATION

LCRD will communicate with optical ground stations at Table Mountain, 

California, and Haleakala, Hawaii. The Table Mountain station, seen above, 

is managed and operated by NASA’s Jet Propulsion Laboratory in 

Pasadena, California. Credit: NASA/JPL-Caltech