Tactical military satellite comms need hardening, says CSBA study


Increasing military use of satellite communication for tactical operations means the Defense Department should create a new tier of protected space systems, says the Center for Strategic and Budgetary Assessments's Todd Harrison.

Currently the Pentagon has a binary military satellite communications architecture – those satellites with a full range of passive defenses to protect against jamming, detection, interception or ground-system attacks, and systems without those defenses, Harrison says in a report (.pdf) released July 24.

The military uses the former mostly for strategic uses such as missile warning and nuclear command and control.

But given a breakdown of a post-Cold War implicit assumption that deterrence would be sufficient to protect American space systems during a conventional conflict, Harrison argues that heavy reliance on satellite communications systems has created an asymmetric vulnerability for U.S. forces – in fact, one that insurgents in Iraq and Afghanistan have already exploited.

For example, Defense analysis of commercial satellite links used by the military during a 16 month period of Operation Iraqi Freedom (the military is a huge consumer of commercial satellite links) identified five suspected instances of hostile jamming targeting uplink signals. All five cases involved a transmitter using a continuous wave carrier signal, meaning the radio interference was unlikely to be an accidental transmission by a friendly user. The interfering signals also had the characteristics of a jamming signal, since they varied center frequency, "what is known as a 'sweeper' signal in jamming because it creates intermittent outages across a wider piece of the spectrum," Harrison writes.

As a result, the Pentagon should create a middle-tier space segment that would deploy some passive defenses, but not to the full extent deployed now to strategic satellite systems – for example foregoing hardening against a nuclear blast.

A new middle tier would also enable new options to reduce costs while expanding protected communications ability, Harrison says. The protected Advanced Extremely High Frequency satellite payload could be deployed onto a non-nuclear hardened satellite bus and share the same ground control infrastructure, he writes. That would serve tactical users needing data links less than 8.2 Mbps; higher bandwidth users could deploy commercially-available direct sequence spread modems to Wideband Global SATCOM system terminals, which would provide more jam-resistant communications relative to non-spread spectrum modems, Harrison says. In the long term, the Pentagon could also modif6y the AEHF XDR waveform to accommodate higher data rates, he adds.

As a result of the new middle tier, Defense should also shift all non-essential communications away from military satellites and instead buy connectivity as a service from the private sector. "The military does not need to pay for the development and added expense of procuring unique military systems for communications that can be adequately served by commercial SATCOM service providers," he says.

Harrison also recommends against the deployment of active defenses in space, shut as a shoot-back capability by satellites, since that would result in a costly arms race. Instead, the military should raise the stakes for a kinetic attack against satellite infrastructure by improving its ability to attack anti-satellite threats on Earth. It should also raise the stakes of attacking a satellite system by bringing international partners into system deployment, for example by deploying U.S. payloads onto a partner nation's satellite bus.

Making a kinetic attack more costly would steer adversaries into other forms of attack, "like electronic and cyber, where the U.S. military can compete on more favorable terms."

He also says military satellite programs, budget and operations should be consolidated into one military service, of which "the Air Force would be the most likely candidate."

For more:
- download the report, "The Future of Milsatcom" (.pdf)

Related Articles:
Auditors fault waterfall development in GOES-R ground system development delays
Dedicated DoD satellite control systems mostly a matter of choice, not necessity
Report: NASA earth observation capability at risk of collapse