Despite tremendous budget uncertainty and a shrinking bottom line, the commander of the Air Force Space Command said that he will do his best to protect all of the Air Force’s satellite constellations.

Speaking with reporters at a recent meeting of the Defense Writers Group, Air Force Gen. William L. Shelton called the range of U.S. satellites a “foundational” capability.

“It doesn’t matter what size the United States military becomes, we count on space and cyber capabilities to underpin the force, to enable the way we fight today, to give us the capabilities we need globally,” the general said.

“You can’t say, ‘Well, I’ll just have one less GPS satellite or one less advanced [extremely high frequency] satellite or one less [space-based radar] satellite,’” he added. “You can’t create holes in the constellation and still have global capability.”

Shelton said that despite fiscal uncertainty, Air Force Space Command seeks to answer growing threats from nations such as North Korea and China in the space domain and modify its satellite architecture in concert with emerging threats.

The North Koreans have tried several times to reach orbit and succeeded Dec. 11, according to North American Aerospace Defense Command officials, and Shelton said that tells the United States two things.

“One is that they can get to orbit now, but if they can get to orbit, they can also launch an [intercontinental ballistic missile]. … That gives us lots of concerns for lots of reasons,” the general said.

“What they would do in space is not as concerning right now, because they are very immature in their space program. … [But] others around the world are very mature and have developed things that we know would be deleterious to our efforts in space,” Shelton added, including China in that equation.

In January 2007, China launched with a multistage solid-fuel missile from the Xichang Satellite Launch Center in southwestern China to destroy one of its own Fengyun-series weather satellites.

“Without talking about intelligence matters, I think it’s safe to say that the Chinese didn’t conduct the 2007 test and just quit,” Shelton said. “They conducted another test in 2009 that, even though it was called an antiballistic missile test, certainly had [anti-satellite]-like ramifications. So I think it’s safe to say that they continue in their efforts.”

To examine its satellite architecture, Shelton said Air Force Space Command is conducting studies to “look at different ideas.”

The advanced extremely high-frequency system, or AEHF, is the next-generation military strategic and tactical relay system for delivering protected communications to U.S. forces and several allies worldwide.

When it’s fully operational, the system will consist of four crosslinked satellites in geosynchronous earth orbit, a ground mission-control center and user terminals. AEHF-1 was launched in August 2010 and AEHF-2 last May. AEHF-3 is expected to launch this fall and AEHF-4 sometime in 2017.

AEHF will provide connectivity for land, air and naval warfare, special operations, strategic nuclear operations, strategic defense, theater missile defense, and space operations and intelligence.

“If you could take the two payloads on that satellite, the tactical payload and strategic payload, and separate them onto different hosted platforms, or [make] the strategic platform a hardened, survivable platform and the tactical platform maybe not quite so hardened, … that’s certainly a path we’re studying, seeing what might be most cost-efficient,” Shelton explained.

For the Air Force’s Space-based Infrared Systems, or SBIRS, program, a critical missile defense and warning capability, the architecture consists of a mix of geosynchronous Earth orbit or GEO satellites, payloads in highly elliptical Earth orbit, and ground hardware and software.

In missile warning, Air Force Space Command is looking at the wide-field-of-view or scanning sensor on GEO satellites and trying to determine whether or not it can host that on a platform other than SBIRS, the general said.

“It’s important to note that for both advanced EHF and SBIRS, the die is cast through about 2025” because of contract commitments, Shelton said.

“I think it’s safe to say in both of those cases, depending on how much money we have in 2015, we’ll look to continue the study efforts to determine cost efficiency,” he said.

The general said studies are ongoing for a weather satellite that will be a follow-on to the Defense Meteorological Satellite Program managed by the Space and Missile Systems Center at Los Angeles Air Force Base in California.

“We’re in the midst of [analyzing] alternatives right now to develop a follow-on weather satellite that will be in the mid-2020 kind of time frame, but looking at making that probably a smaller satellite and much less expensive,” Shelton said.

Studies also continue for the follow-on to the Space-based Surveillance System, part of the U.S. Strategic Command's Space Surveillance Network and operated by the 1st Satellite Operations Squadron at Schriever Air Force Base in Colorado.

The SBSS satellite is the only space-based sensor in the network, operating 24 hours a day, seven days a week to collect about man-made space objects.

“We firmly believe that space-based space surveillance is something we need to continue,” Shelton said. “The question is exactly what should that satellite look like?”

The Global Positioning System, a constellation of more than 24 dual-use satellites that provides positioning, velocity and timing to military and civilian users around the world, is a joint service effort directed by the Air Force.

“We’re doing great on GPS,” Shelton said, adding that the Air Force may look at an “augmentation, navigation-only kind of satellite that doesn’t have the nuclear-detonation-detection payload on it, so we could have a fairly inexpensive satellite that addresses some lack of coverage in urban canyons, for example.”

The general said he also will try very hard to protect funding for the Joint Space Operations Center Mission System.

JSPOC includes personnel from all four services and from the United Kingdom, Australia and Canada, along with facilities and equipment needed to give U.S. Strategic Command's Joint Functional Component Command for Space the ability to plan and execute command and control of worldwide space forces.

“The JSPOC Mission System out at Vandenberg [Air Force Base in California] underpins all space operations,” Shelton said. “Everything we do starts with what happens at the JSPOC.”