OPALS, or the Optical Payload for Lasercomm Science, beamed a high-definition video via a laser from the International Space Station (ISS) to the Earth’s surface on June 5th. The ground breaking video that was transmitted via light was 30 second homage to the output of the first computer output titled Hello World.
The OPALS mission is similar to the LLCD mission that was conducted during October 2013. During this mission, NASA transmitted data at 622 Mbps from the Moon to the Earth via a beam of light. With NASA’s intense study of communications using lasers, it would appear that the space agency is ushering in the next generation of communication technology.
The idea of using lasers instead of radio frequencies to communicate has profound implications for the entire world. In a press release, Bogdan Oaida, Project Systems Engineer for OPALS, described it as “upgrading from dial-up to DSL”.
Oaida explained that the amount of data that NASA can produce far exceeds their ability to download it. For those of us who remember the days of dial-up (or those who unfortunately still have to deal with dial-up), it would be like attempting to download a movie at those speeds. For those of you who never had to deal with the bad ol’ days of dial-up, NASA’s current dilemma is like trying to download 2 gigs at 56 Kbps.
Taking some overhead into consideration, you would have your movie downloaded in about 100 hours. At the amount of data that NASA currently generates, this speed of communication, which is currently provided by Radio Frequency, is unacceptable.
The Advantage of Lasers
NASA’s research has shown that using lasers instead of radio frequencies would allow data to be downloaded at least six times faster. These download speeds have significant implications here on Earth and for use during deep space missions. Currently, NASA is communicating somewhere around 200 kilobits per second.
However, OPALS has the potential to increase that communication speed to 50 megabits per second. Additionally, with what is learned from the OPALS mission, future Optical Laser Communication systems could easily provide one gigabit per second communication speeds. Such speeds would give NASA data rates that are upwards of 1000 times higher than their current capabilities.
The foundation of the lasercomm is a dead eye aim and 2.5 watt laser. Due to the speed of the Earth’s rotation and the speed that the ISS is traveling, the best marksmen in the world could not hit the ISS from the ground nor could they hit the ground station from the space station. Therefore, OPALS was locked onto a tracking beacon located at the Optical Communications Telescope Laboratory at the Table Mountain Observatory in Wrightwood, California.
Once locked onto the beacon, OPALS transmitted the hi-def video via a 2.5 watt 1,550-nanometer laser at a speed of 50 megabits per second. Though multiple copies of the video was transmitted, it only took OPALS 3.5 seconds to transmit a single instance of it. Using the current radio frequency method of transmission, it would have taken roughly 10 minutes to transmit the same video.
In another press release, Matt Abrahamson, OPALS mission manager at NASA’s Jet Propulsion Laboratory, stated that the success of OPALS initial transmission will hopefully lead to use of lasercomm as the new standard in deep space communications.
“We look forward to experimenting with OPALS over the coming months in hopes that our findings will lead to optical communications capabilities for future deep space exploration missions.”
It is also safe to assume that if successful for NASA, lasercomm technology will eventually be used in commercial applications here on Earth.