Why in News?

• Recently, NASA launched its new Laser Communications Relay Demonstration (LCRD) — the agency’s first-ever laser communications system from Cape Canaveral Space Force Station in Florida, USA.
• The LCRD will help the agency test optical communication in space.
• Currently, most NASA spacecraft use radio frequency communications to send data. Optical communications will help increase the bandwidth 10 to 100 times more than radio frequency systems.

• LCRD will demonstrate all of the advantages of using laser systems and allow us to learn how to use them best operationally.
• With this capability further proven, we can start to implement laser communications on more missions, making it a standardized way to send and receive data.
• LCRD has two optical terminals – one to receive data from a user spacecraft, and the other to transmit data to ground stations.
• The modems will translate the digital data into laser signals. This will then be transmitted via encoded beams of light. These capabilities make LCRD NASA’s first two-way, end-to-end optical relay.

Laser VS radio

• Laser communications and radio waves use different wavelengths of light. Laser uses infrared light and has a shorter wavelength than radio waves. 
• 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.
• Using infrared lasers, LCRD will send data to Earth at 1.2 gigabits-per-second (Gbps). At this speed, it will take less than a minute to download a movie.

Other advantages

• Optical communications systems are smaller in size, weight, and require less power compared with radio instruments. 
• 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.
• With optical communications supplementing radio, missions will have unparalleled communications capabilities.

Reference:

1. https://indianexpress.com/article/explained/explained-what-is-nasas-new-communications-system-lcrd-its-importance-7661272/