MIT engineers' record-breaking information system is 1,000 times faster than traditional method
In groundbreaking news, MIT announced on November 30 that engineers at the Lincoln Laboratory had broken the record for the fastest laser link from space with its TeraByte InfraRed Delivery (TBIRD) system.
The TBIRD payload, launched into orbit in May 2022, has sent down data at a speed of up to 100 gigabits per second through an optical communication link to a ground receiver in California. The new record is around 1,000 times faster than traditional methods. This means that sending information to and from space will see tremendous improvement with this new technology.
Traditionally, radio-frequency links used for satellite communication had a speed rate of 0.1MB per second. That means the MIT engineers' new technology is confirmed to be 1,000 times more than the traditional method. SpaceX’s Starlink satellite internet service averages between 20MB to 100MB, which is still way short of the TBIRD system.
The infrared light used in the TBIRD is very different from traditional radio waves, as the infrared light sends data in significantly tighter waves. With the TBIRD capable of sending up to 200 gigabits per pass, the difference between it and radio-frequency links is highly significant.
How MIT engineers pulled off the TBIRD system
MIT’s engineers were able to pull off the TBIRD payload, which is around the size of a tissue box, by using three readily-available components:
An optical signal amplifier
A sizeable high-speed storage drive
A high-rate optical modem
The engineers put these components through radiation, shock, vibration, and thermal-vacuum tests to ensure they would fare well in space. Upon testing, some of the components were then modified to suit the space.
The signal amplifier was put through a thermal test that simulated the environment in space – its fibers melted, and a modification had to be made. The laboratory program manager for the TBIRD payload and ground communications, Jade Wang, explained the reason for the modification.
He stated there's no atmosphere in a vacuum, which means heat cannot be released by convection. According to Wang, the team partnered with the amplifier’s manufacturer to release heat through conduction instead of convection.
Data loss was also a possible atmospheric problem, and the lab dealt with it by developing its own version of Automatic Repeat Request (ARQ). The ARQ is a protocol used to control errors in transmitting data over a communications link. With the ARQ, the receiver tells the payload which frames were received correctly. This allows the payload to know which frames to re-transmit.
In the end, the future of laser communications is bright, and the potential capabilities of the TBIRD are limitless.
Dr Shenlong Zhao on why his development could change the world.