WASHINGTON — As NASA pushes ahead with plans to modernize its space telecommunications systems — elements of which have not been updated since the 1980s — the agency also expects to stand up by 2018 a next-generation data network that will consolidate current space and ground assets with new technologies into a single, unified architecture in support of future exploration missions.
Managed by the Space Communications and Navigation Office (SCaN), NASA’s communications infrastructure comprises a global patchwork of ground stations, low-Earth-orbiting spacecraft and deep space probes that provide the backbone of data-relay services for communication among NASA and other federal government agencies active in space.
BadriYounes, deputy associate administrator for SCaN, said NASA has failed to adequately fund upgrades to these communications and navigation networks in recent years. In an interview with Space NewsYounes said he is prepared to look within SCaN’s annual budget of between $450 million and $500 million for additional resources as his office continues to rehab existing assets on a path toward a new, integrated telecommunications architecture later this decade.
“We are trying to manage priorities smartly and reprogram money in guide, so that we don’t have to submit proposal after proposal to the administration for more funding,” he said. “We’ve identified a number of efficiency initiatives that resulted in a cost savings, so we challenged our engineers to kind of target the areas where cost reduction can be achieved while maintaining the same cost performance and commitment to our customers. I have the flexibility that will allow me to adjust or accommodate any budgetary situation over the next decade.”
President Barack Obama’s $19 billion budget proposal for NASA includes $453 million for Space Communications and Navigation in 2011, part of a five-year funding profile that gradually ramps up to $490 million by 2015. Younes said additional funding is provided in a technology funding line to help with future upgrades.
Younes said his office was formed in 2007 to consolidate management of NASA’s three aging space communications networks in an effort to save money and reduce redundant capabilities. These include the Near Earth Network, Space Network and Deep Space Network, all of which are undergoing some form of review and rehabilitation as SCaN prepares to merge them into a single integrated architecture by 2018.
“The NASA position was that much of all of these efforts can benefit from a common approach to building a united, single network, the network of networks that will not only address the obsolescence but also build for the future and enable data rates much, much higher than presently available to our users,” Younes said, adding that the consolidation effort is “driving us toward some cost savings of about 40 percent on what we are presently paying.”
As network systems age, they require more maintenance, “so even though you are not refurbishing or paying the money to add new technology, you are paying for a marching army to maintain the old stuff and much of the components have become obsolete,” he said. “Our engineers have to go on eBay to buy some of these components because they are no longer on the shelf.”
One of SCaN’s largest projects will begin this year as the agency replaces its Deep Space Network, comprised of three ground stations, each equipped with a 70-meter aperture antenna. Located in Australia, California and Spain, this network of giant satellite dishes has communicated directly with deep space probes for half a century, when the first giant antenna was constructed in Canberra, Australia, 50 years ago this month.
“These are kind of national monuments,” Badri said. “You only have to see the 70-meter antenna and the size, it’s a huge system, and so we look at it with respect.”
Younes said NASA will begin implementing a plan to replace the enormous dishes with 34-meter antenna arrays that can provide similar or in some cases improved performance compared with the existing capability, and at a lower cost.
“So instead of relying on a single dish that sometimes may break and require maintenance, it is better to build an array that has an equivalent of much better performance than a single antenna,” he said.
The first upgrade, slated for some time in 2010, would replace the 70-meter antenna in Canberra with four 34-meter antennas, Younes said.
“When done with upgrades of all three locations, there will be at least four 34-meter antennas at each site,” he said, adding that the replacement effort would be completed by 2025 at a cost of $420 million.
Although NASA intends to replace its outmoded dish network, Younes said the agency may find some resident capability suitable for future use, including radio-astronomy and the detection of potentially hazardous asteroids and other so-called near-Earth objects.
“If we can identify any potential usage we are going to ensure it, if we can still do it at an affordable price,” he said. “As equipment gets old, it becomes a problem finding spare parts and components and things like that. … Seventy-meters are great, but structurally speaking they cannot be converted to support new technologies.”
SCaN is also pursuing an effort to evolve a software-defined radio that would give on-orbit spacecraft greater flexibility in the event of a communications failure.
Younes said software-defined radios can be reconfigured “on the fly” to provide a more robust system that can accommodate rapidly changing situations during missions. SCaN is overseeing development of a test bed slated to fly on the international space station for three years beginning in 2011. The experiment is designed to test and validate different waveforms of various frequency bands, including L-band.
“The test bed will be on station to provide our ground engineers with on-orbit capability to test new communications protocols in an operational environment, as opposed to being tested in a lab,” he said.
NASA also is upgrading its Space Network, which comprises a space segment that relies on NASA’s eight Tracking and Data Relay Satellites (TDRS) and two ground segments located at the White Sands Complex in Las Cruces, N.M., and the Guam Remote Ground Terminal on Guam. Younes said SCaN is focused on building additional TDRS spacecraft to support NASA and other government customers with near real-time data relay.
NASA’s 2011 budget request includes funding to continue development of two TDRS replenishment satellites, TDRS-K and TDRS-L.
The satellites are being built by St. Louis-based Boeing Defense, Space and Security under a $695 million contract and are slated for launch in December 2012 and December 2013, respectively. Younes said TDRS-K is undergoing its critical design review at Boeing’s satellite development center in El Segundo, Calif.
“That’s a major milestone before we begin putting the hardware and software together,” he said. “We will add more spacecraft to the constellation and continue within the next few years to converge toward the fourth-generation architecture where we will have much better capabilities than present.”
In addition, NASA expects to proceed with plans to award a Space Ground Systems Segment contract and conduct a system readiness review by the third quarter of 2010. Younes said the contract would support a modern communication system with a flexible ground segment that would allow the Space Network to maintain its current level of service while accommodating new users and reducing the effort required to operate and maintain the system in the future.
“You cannot keep on operating a system that was designed decades ago to meet the needs of the future,” he said. “This will fix the aging problem and build toward the integrated architecture that NASA has targeted for 2018 to make happen. Everything we do is done remotely and requires the use of communications assets. Without communications, there is no NASA.”