NASA
needs to transition to optical communication systems that would allow
spacecraft to send high-definition video and other high data-rate products back
to Earth — the kind of data that would overwhelm the radio frequency systems
used today, said NASA Administrator Mike Griffin.
Speaking
to an international conference of electronics experts Sept. 15 in Pasadena,
Calif., Griffin outlined a new in-space communications architecture that
gradually would replace the Deep Space Network that has served the U.S. space
program since its inception in 1958.
"If
the truth be told, the Deep Space Network is 50 years old, not 50 years
young, and it is showing its age," Griffin said in a speech at the 33rd
International Conference on Infrared, Millimeter and Terahertz Waves. The
conference was held at the California Institute of Technology, which manages
NASA's Jet Propulsion Laboratory — home to core elements of the Deep Space
Network.
Griffin
said NASA has spent "the past few years" defining a new
communications architecture for future human spaceflight missions as well as
Earth and space science programs. "We want an integrated, scalable
communications network offering exponentially higher data rates," he said.
Designing
a communications systems to meet the agency's needs for the next 50 years
"will be no mean feat," he added. "We should not build simply to
meet minimal requirements, but to enable qualitatively new capabilities."
To prepare
for the challenges ahead, NASA has spent the last few years under Griffin
consolidating the management and budget for the agency's space communications
and navigation activities into a centralized organization.
"We
used this approach in the old NASA Code O, and I believe it was a mistake to
get rid of it," Griffin said. "We've re-established it within our
Space Operations Mission Directorate."
By
centralizing the management and systems engineering of the agency's previously
separate Deep Space Network, Near Earth Network and Space Network, Griffin
hopes to wring more from the agency's current communications budget. However,
he said it will take more than centralized management to bring about the space
communications network of the future.
"With
our current budget, we can afford to operate and maintain the aging [Deep Space
Network] or we can afford to build a new, integrated communications network. We
cannot afford both," he said. "Thus, we must be more efficient with
automation, commonality, and interoperability between the various
communications networks, including those of our international partners, so that
we invest the savings in building future capabilities."
Griffin
said shifting to an optical communications network will enable
"exponentially higher data rates" than now are possible with NASA's
current systems.
"Rather
than returning grainy images like those from the first moon landing, we will be
able to stream high-definition video upon our return," he said.
To help
bring about this future, Griffin said NASA will develop a medium-sized optical
payload and pathfinder data relay satellite, although he did not say when. A
NASA official said more specifics would be detailed in NASA's 2010 budget
request, currently in work for release in early 2009.
Griffin,
however, said the NASA demonstration mission would leverage the work of the
National Reconnaissance Office on the GeoLITE satellite, a $130 million
technology demonstrator that was launched on a nominal nine-year mission in
2001 aboard a Delta 2 rocket. Among GeoLITE's payloads was a laser
communications experiment developed by the Massachusetts Institute of
Technology's Lincoln Laboratory.
Griffin
said in his speech that he has directed Ed Weiler, NASA's associate
administrator for science, to identify spacecraft missions in formulation suitable
for hosting optical communications demonstrations.
Griffin
also told the audience NASA hopes to phase out the Deep Space Network's aging 70-meter antennas and
replace them with smaller but more numerous Ka-band antennas.
NASA's 2008 budget included
just over $300 million for space communications. About half that amount is
dedicated to the purchase of new Tracking and Data Relay Satellites used by
NASA to communicate with the space shuttle, international space station and
other spacecraft in low Earth orbit.
