Laser Communications Relay Demonstration

Q Why is it in News?

A NASA has launched its new Laser Communications Relay Demonstration (LCRD) — the agency’s first-ever laser communications system.

Q What is LCRD?

A 

• LCRD involves laser communications – also called optical communications which uses infrared light to send information.
• LCRD is launched in a geosynchronous orbit, over 35,000km above Earth.
• 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.

Q What are the benefits offered by LCRD?

A 

• 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.
• The LCRD will help the agency test optical communication in space.

Q What is difference between Laser and Radio waves?

A 

• Laser communications and radio waves use different wavelengths of light. It uses infrared light and has a shorter wavelength than radio waves.
• This will help the transmission of more data in a short time.
• Using infrared lasers, LCRD will send data to Earth at 1.2 gigabits-per-second (Gbps).
• 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, says NASA.

Q What are its other advantages?

A 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.