

Army unit deploys an inflatable satellite antenna. (Photo: Jett Loe, Sun-News)

The information relay from an unmanned aircraft system (UAS) is only as good as the connection, and there are limited options for transmitting information, particularly in theater, where there is limited infrastructure. Historically, drones used radio waves to be able to fly within line of sight of the operator. But now, with Reapers flying halfway around the globe from the command center, satellite communications (SATCOMs) are essential to drone operations — particularly for medium-altitude, long-endurance (MALE) aircraft, but also for smaller platforms.

Nevertheless, the legacy networks these unmanned aircraft rely on have their limitations. First is the nature of the satellite hardware itself. Until space-bound robots can go up and tinker with decades-old satellites — a real idea that’s been floated by the Defense Advanced Research Projects Agency (DARPA) — satellites are not going to change. As a result, the military needs software-based solutions to upgrade its legacy SATCOM networks to keep up with the proliferation of unmanned aircraft.

Second is the nature of physics itself. There is only so much the military can do to drive down latency — at the end of the day, information relay is a basic equation based on the maximum transmission speed of electromagnetic waves over a distance. The same reason it takes NASA 20 minutes to talk to a rover on Mars is at play on a smaller scale when it comes to operating an UAS.

These limitations may make it seem like there is no way around improving SATCOMs, but that couldn’t be further from the truth. Instead, UAS operators can leverage modernized networks that not only improve the reliability of a connection, but also help them by automatically switching feeds, without the need for manual intervention. Additionally, UASs are increasingly targets of network jamming and potential cyberattacks, and a modernized network is more capable of ensuring the fidelity of a connection against the Department of Defense’s (DOD) adversaries.

Sophisticated medium-altitude, long endurance (MALE) aircraft like this General Atomics MQ-1C Gray Eagle UAS increasingly depend on satellite communications for command and control. (Photo: U.S. Army)

Upgrading Networks

There’s no such thing as ripping out and replacing a network — not just for the military, but in any commercial operating environment as well. That means that networks that were built for different missions must transform into agile, flexible, automated and secure networks. Doing so requires an emphasis on software upgrades.

Over the years, SATCOMs have been able to provide significantly more bandwidth through upgrades, enabling the transfer of megabytes instead of kilobytes of data. By using optimization protocols, that bandwidth can become even better; however, that doesn’t necessarily equate to more reliable data transfer. Unlike TCP protocols, where every single bit of information gets packeted and transferred from Point A to Point B, a lot of the information drones relay instead follow UDP protocols, which are used for video transfer. In these transfers, the packet doesn’t necessarily get transmitted in its entirety, the same way it would if a television or phone line cut out, the receiving end wouldn’t get the remaining bits of information relayed after a disruption. Command and control would prefer that UAS have a more reliable connection for video, but reliability comes at a price — typically reduced speed.

In order to upgrade these older software solutions, the military needs to have a modernized network that can ride on top of the legacy network — a software-redefined network. These newer networks can control where traffic goes and what path it takes by using this software-defined overlay. The legacy network is like the original dirt road, while the software overlay is like pavement that lets the cars on the road go at much faster speeds.

But to be truly effective, this network upgrade must provide end-to-end visibility from the application to the end user, all the way back to the data center or the battalion commander in theatre. Without visibility, the military can’t optimize for latency issues, which are inherent to operations but can be minimized.

Adding Autonomy, Encryption

There is much more at play than latency issues for the modern warfighter relying on UAS for information in theatre. A network must be much more than fast — it must also be automated and secure.

Connecting to SATCOM links is an advanced technique that often requires a more in-depth skill set than our current warfighters possess — plus in the heat of combat, no one wants to be scrambling to fix or find a new comms link. The answer to this is automated, self-healing networks. Additionally, if there is an issue with the connection, a network must be automated to self-heal, requiring as little manual intervention as possible to get back online.

Encrypting networks is a difficult but increasingly important task as cybersecurity issues continue to proliferate. Traditionally, military-grade encryption needed to come from a group within the military. Because these networks are not automated or self-healing,it could take up to a half-hour to get a comms link back after detecting an encryption issue. As an alternative, the military should seek Type 1 cryptographic products, which are rigorously tested by the National Security Agency (NSA) to prevent tampering. It’s paramount that adversaries are not able to intercept the data collected by UAS to accomplish the DOD’s mission goals. Without strong encryption, there are potentially worse consequences, like the ability of the enemy to take remote control of a UAS — an occurrence which has precedent with Iran’s capture of the RQ-170 in late 2011.

Faster, more secure networks could boost drones when they are used as more than the endpoint of a global comms network. If the military opts to use drones as communications relays, having this added network durability and security is a must. Particularly if the military is using more than one drone as a relay, it will need an automated system so different UAS can take over as the main point of contact in the network.

Optimizing Networks

Ultimately, SATCOMs are a tricky business in warfare. They are not perfect, but they are the best solution the military has for around-the-world connectivity. The key is ensuring these networks are able to handle the needs of both UAS command and control and the reality of petabytes of data coming off these systems every year is software optimization. This will allow the military to tap into the added benefits of self-healing, automated networks that are as secure as possible to enable UAS’ global mission to extend the reach of the warfighter.

This article was written by Marlin Mc-Fate, Federal CTO, Riverbed Technology (Reston, VA). For more information, visit here .

Aerospace & Defense Technology Magazine

This article first appeared in the September, 2018 issue of Aerospace & Defense Technology Magazine.

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