News Brief
Illustration of NASA's LCRD communicating over laser links. (PC: NASA)
After tremendous anticipation and a two-year wait, the Laser Communication Relay Demonstration (LCRD), NASA's first laser communication system, was launched on 7 December from Cape Canaveral Space Force Station in Florida to test optical communication in space.
The LCRD will replace radio frequency to deliver data with a 10 to 100-fold increase in bandwidth over current radio waves. NASA's Goddard Space Flight Center in Greenbelt, Maryland, Principal Investigator David Israel said that the LCRD will demonstrate how to use laser systems for space communications and that lasers will soon be able to be used on more missions as a standard mode of communication.
To receive and transmit data to user spacecrafts and ground stations, there are two optical terminals equipped in LCRD. The digital data will be converted into laser pulses by the modems, which will then be conveyed by light beams that have been encoded.
According to the news release by NASA, the LCRD will demonstrate the space agency’s first two-way laser relay communications system, sending and receiving data via infrared lasers that are undetectable to the bare eyes. It is led by NASA's Goddard Space Flight Center in Greenbelt, in collaboration with NASA's Jet Propulsion Laboratory in Pasadena, California and the Massachusetts Institute of Technology's (MIT) Lincoln Laboratory.
Different wavelengths of light are used in laser communications and radio waves. Infrared light is used in lasers, which has a shorter wavelength than radio waves. This will allow more data to be transmitted in a shorter amount of time. As explained by NASA, from geosynchronous orbit to Earth, LCRD will send and receive data at a rate of 1.2 gigabits per second—enough to download a movie in under a minute at that speed.
Radiofrequency systems are larger, heavier and consume more power than laser communications systems. These benefits, paired with the larger bandwidth of laser communications, can help robotic and human exploration across the solar system.
Badri Younes, who is the deputy associate administrator for NASA’s Space Communications and Navigation Program at NASA Headquarters, said: "LCRD is NASA’s key milestone for the buildup of the ‘Decade of Light’ initiative, which involves the infusion of optical technology into space communications and navigation.”
“By the 2030s, we expect optical technology to play a critical role in enabling an interoperable, reliable, and robust space communications infrastructure, providing seamless operations and roaming capability between government and commercial users and providers," he added.
The LCRD will spend the next two years conducting experiments, examining how weather and other changes in the Earth's atmosphere can affect laser communications and measuring link performance in order to improve its operational capabilities and processes. Some experiments will replicate relay scenarios between the Moon and Earth to learn more about how laser communications can be employed in NASA's Artemis missions or crewed Moon landing missions in the future.
However, later in its mission, LCRD will act as a relay between the International Space Station's (ISS) optical communications terminal and ground stations on Earth. The Integrated LCRD Low-Earth Orbit User Modem and Amplifier Terminal, developed by NASA, will be the first demonstration of a fully working end-to-end laser communications system from space.