The Laser Communications Relay Demonstration (LCRD) will fly as a hosted payload aboard a U.S. Air Force spacecraft as part of the Space Test Program (STP-3) mission. LCRD will continue NASA's exploration of laser communications to support future missions to the Moon and beyond. Laser communications will enable better data rates, making possible new capabilities such as 4K ultra-high-definition streaming from beyond Earth orbit. It will also allow communications systems to become smaller, lighter, and more efficient. LCRD will demonstrate the technology over several years before laser communications becomes operational for future NASA missions.
LCRD will "relay" data between two ground stations, the JPL-managed Table Mountain Observatory in California and another ground station in Haleakala, Hawaii. This means it will receive data from one station before sending it on to the next, serving as a communications go-between. This mimics the way a future laser communication network might receive data from a spacecraft before forwarding it on to a ground station on Earth.
Later in its mission, LCRD will relay data between the International Space Station and the ground. This will be the first operational use of laser communications at NASA. LCRD will send data to, and receive data from, an optical communications instrument called the Integrated LCRD Low-Earth Orbit User Modem and Amplifier Terminal (ILLUMA-T). ILLUMA-T will be the first demonstration of a fully operational, end-to-end optical communications system, providing the space station a state-of-the-art optical communications terminal with improved size, weight, and power over comparable radio-frequency communications systems.
Laser communications systems like LCRD can transmit 10 to 100 times as much data per second than current systems, meaning a message or data set can get to Earth more quickly. This is because laser communications uses infrared waves, which are much smaller and more frequent than radio, to communicate. If each waveform carries one bit of data and infrared has many more waveforms per second than radio, the whole set will arrive at Earth more quickly.