By Jeremy Hsu
SPACE.com Contributor
SPACE.com Contributor
Rovers and deep space probes can forget about quickly posting cool high-definition videos to YouTube, given the painfully slow data transfer rates for most of today's space missions.
But NASA wants to change that by fusing together three aged space communication networks into a much faster, more efficient data network worthy of 21st century missions to the moon, Mars and beyond. And it hopes to do it all without costing taxpayers an extra cent.
NASA's overhaul aims to boost space communication by as much as 50 times faster than today's data transfer rates, so that a Mars mission squeaking by on a few megabits per second might someday get as much as 600 megabits per second, if not more. That could enable far more scientific payoff per mission in the long run.
An upgraded network might support the very quick upload or download of huge video files the size of an HD YouTube video, as opposed to current capabilities that would struggle to transfer mp3 music files.
Younes worked at NASA's Goddard Space Flight Center for a decade before leaving to join the U.S. Department of Defense. But the U.S. space agency hired him back in August 2007 for the purpose of revolutionizing its space communication networks.
From Chevy to Lamborghini
Younes faces the tricky task of creating a new space communication network out of NASA systems that have not had upgrades since the early 1990s. He also must ensure that the rebuilding period does not interfere with NASA's support of ongoing space missions, ranging from the International Space Station to Mars orbiters.
"It's like driving a 1960s Chevy that's beat up and losing paint while going at 90 mph, and being pushed to convert that into a Lamborghini while driving 90 mph without losing a beat," Younes told SPACE.com.
The challenge goes beyond consolidating command centers and launching new satellites to support NASA's Space Network (SN), Near-earth Network (NEN), and Deep Space Network (DSN). Younes has already begun to reduce maintenance and operation costs by putting in new automated and smart systems, so that he can transfer the cost savings within his $400 million annual budget into new space communications capabilities and technologies.
In the past, NASA has cobbled together its space communication networks based on the demands of each new space mission. But that piecemeal approach has limited the technological upgrades, because each mission had to pay out of its own pocket.
By doing a wholesale upgrade of a unified space communication network, Younes can offer mission managers capabilities that they would otherwise have never dreamed of. He has already targeted 2018 as the latest date for integrating the three existing space networks.
Lasers point to the future
The U.S. space agency is already pushing new communication innovations such as disruption tolerant networking. The NASA-developed Internet protocol ensures that communication delays or disruptions from solar storms won't disrupt the flow of data packets across space networks, and has undergone testing in near-Earth as well as deep-space missions.
Speed boosts may come from newer Ka-band transmitters that still work in the radio spectrum — the Lunar Reconnaissance Orbiter can send or receive 100 megabits per second with its Ka-band transmitter. NASA also plans to implement communication protocols that can increase the virtual bandwidth available to space missions,
But one of the biggest communication revolutions will come from laser-driven optical communication, as opposed to current space communications based on radio frequencies. Lasers could allow data transfer speeds of up to 600 megabits per second, as Younes hopes, or perhaps even speeds surpassing 1 gigabit per second (1 gigabit = 1024 megabits) from the moon or Mars. That data stream could be even higher for a near-Earth spacecraft or outpost such as the space station.
NASA has already enlisted the help of MIT to build and demo a laser communications system aboard the Lunar Atmosphere and Dust Environment Explorer, slated for launch in late 2011. A successful test would go a long way toward ensuring that NASA's Constellation astronauts returning to the moon have a much faster connection to Earth.
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