A team of NASA researchers has been entrusted with the task of developing a specialized modem that could allow spacecraft and ground stations to communicate at speeds 10 to 100 times higher than today’s radio frequency (RF) systems. Scheduled for testing aboard the International Space Station in the year 2020, the mobile phone-sized contraption uses light-based technology to transmit data at incredibly high speeds. The research is part of a bigger project, known as Laser Communications Relay Demonstration (LCRD).
Described as the world’s first “integrated-photonics modem”, the device contains a one-of-a-kind microchip, featuring a host of optics-based components, including lasers, wires and switches. It marks a shift from radio frequency communication – a technology that NASA has been using since its inception back in 1958 – to a faster and more efficient laser-based communication system. The technology, according to the scientists, could revolutionize the way the space agency sends and receives data, such as videos, documents and others, using lasers to transmit information at rates around 10 to 100 times faster than currently-available systems.
What is more, the modem is significantly lighter and more energy-efficient than existing equipment. In 2013, laser communication systems on board the Lunar Atmosphere and Dust Environment Explorer (LADEE) allowed NASA to achieve record-breaking upload and download speeds of about 20 Mbps and 622 Mbps respectively, while orbiting the moon. Once fully developed, the new technology could enable high-speed data transfer between ground stations and spacecraft present in different parts of our solar system. This could in turn facilitate deep-space exploration, allowing astronauts to thoroughly study and document the conditions on other planets, similar to the way climatologists predict hurricanes and weather changes on Earth.
Dubbed as Integrated LCRD LEO (Low Earth-Orbit) User Modem and Amplifier (or ILLUMA), the modem will undergo testing right from 2019, when data transmission speeds between geosynchronous orbit and ground stations will be calculated. Later, the setup will be used to measure communication rates between geosynchronous and low-Earth-orbit space shuttles. With several complex functions squeezed into a single microchip, the device relies on integrated photonics technology to deliver data at incredibly high speeds. Speaking about the study, Don Cornwell of NASA said:
Integrated photonics are like an integrated circuit, except they use light rather than electrons to perform a wide variety of optical functions. This technology will enable all types of NASA missions, not just optical communications on LCRD.
Recent advances in meta-materials, nanostructures and silicon-based technologies have broadened the applications of photonic circuitry, while also making it more efficient and easy to build. What is more, these optical chips can be manufactured lithographically, in bulk as well as at low costs. Talking about the modem, which is currently being developed at NASA’s Goddard Space Flight Center in Maryland, Mike Krainak said:
The technology will simplify optical system design. It will reduce the size and power consumption of optical devices, and improve reliability, all while enabling new functions from a lower-cost system. It is clear that our strategy to leverage integrated photonic circuitry will lead to a revolution in Earth and planetary-space communications as well as in science instruments.
The modem, the scientists believe, could replace bulky fiber-optic receivers used by NASA in today’s spacecraft. If everything goes according to plan, it won’t be long before individual satellites can communicate with one another, using ILLUMA. It is a well-known fact that photonic circuits could help miniaturize electronic devices. In addition to faster space-based and inter-planetary communications, the new technology could bring about massive changes in other fields, including medical imaging, national defense, manufacturing and so on. Krainak added:
What we want to do is provide a faster exchange of data to the scientific community. Modems have to be inexpensive. They have to be small. We also have to keep their weight down… Google, Facebook, they’re all starting to look at this technology. As integrated photonics progresses to be more cost effective than fiber optics, it will be used. Everything is headed this way.