Using SDR techniques to provide drone security

Drones can be beneficially used in many applications, including sports broadcasting and wildlife preservation wilderness surveys. Offering powerful intelligent software, drones are becoming less expensive and easier to use, with substantial operating range. But, there is also a lot of negativity around their use.

As with any disruptive technology, drone operation often attracts bad actors looking to exploit the capability for less-than-noble objectives. Some reports have shown unmanned commercial drones being used for unwanted surveillance and even disrupting commercial airspace.

Fortunately, many strive to counter these bad actors by developing drone defence systems. Most drone defence systems leverage technology to detect and defeat threats. These systems use both active and passive radar, and many leverage optical verification. Defeat methods vary, from non-destructive communication interception and GPS jamming, to using destructive countermeasures such as munitions or directed high-power lasers.

Key drone defence system technology challenges

Every year, newer, more intelligent commercial drones offer increasingly more sophisticated command and control (C2) and navigation systems. Today, it’s not uncommon for a drone to have active object avoidance and autonomous modes. When a drone isn’t under direct pilot control, it makes C2 countermeasures difficult; thus, it is common to disrupt or deny GPS with either spoofing or jamming.

Drones with active remote piloting offer a variety of communication methods, ranging from basic analogue modulation to highly secure digital links with encrypted commands. Traditionally, you might consider using a legacy high-power jamming technique; however, these can be quite disruptive to friendly forces and can compromise a stealth operation—not to mention dealing with regulatory obstacles in many countries. Making a single defence system adaptable to target the wide range of C2 disruption methods is a considerable challenge.

First, how do you keep pace with technological evolution and field new threat countermeasures quickly? Because traditional long Department of Defence (DoD) programme development cycles may be incompatible, many systems have moved to commercial off-the-shelf technology for faster deployment so that system designers can focus on the threat instead of hardware implementation.

Second is the question of mobility: While base protection is important, many military operators need to deploy an effective countermeasure solution on vehicles in remote areas. Many times, they lack the luxury of a vehicle with the capacity to house a full-scale radar system that includes cameras and destructive countermeasures. Mobile systems must maintain stealth and a long operational life on mission; thus, it often comes down to SWaP. Choosing a platform that can go from prototype to deployment and meet SWaP and radio performance standards is important.

Figure 1. USRP X310 test with drone

The SkySafe drone defence solution

SkySafe is an innovative, US-based company with the mission to deliver world-class non-destructive drone defence and airspace control solutions. By applying advanced radio engineering and deep threat analysis, the company provides provide comprehensive airspace awareness and control solutions to military, public safety, and commercial customers.

The SkySafe solution employs non-destructive countermeasures by disrupting the C2 and navigation systems of many common threats. Additionally, SkySafe software can intercept navigation downlink reports and passively display drone locations to an operator in real time. As regulatory space is evolving, SkySafe has focused on military drone defence applications and delivered solutions under DoD contract.

Figure 2. SkySafe rugged drone defence enclosure with National Instruments (NI) USRP X310

To combat both technology evolution and SWaP challenges, SkySafe built its system on National Instruments (NI) commercial SDR technology. By combining NI SDR with open source software, SkySafe can rapidly adapt to evolving threats by simply deploying new algorithms, which reduces the time and cost to deploy new capabilities. Key to the SkySafe solution’s effectiveness is its proprietary innovative software radio algorithms.

The SkySafe drone defence system uses the NI brand Ettus Research USRP X310 SDR, the GNU Radio open source software community, and the RFNoC, a flexible FPGA framework. The USRP X310 is designed for adaptability, making it perfect for a rapidly developed, highly adaptable, low-power mobile application. According to Scott Torborg, SkySafe CTO, “The National Instruments Ettus Research USRP X310 is the only commercially available SDR with the openness and raw RF and DSP capabilities to meet the needs of this rapidly evolving drone threat.”

To solve for form factor and ruggedisation, the SkySafe solution repackages the USRP X310 into a sturdy vehicle-mount enclosure (see Figure 2). Environmental protection and system hardening have been a part of the SkySafe design from the outset, and NI’s support in adapting the USRP X310 was key to meeting SkySafe’s environmental requirements.

 Figure 3. SkySafe drone defence system mounted on a military vehicle


Drones are fun and useful technology; however, some seek to exploit this disruptive technology with bad intent. Defending against this new threat presents both technological and regulatory challenges. As regulations evolve, most drone defence development targets military applications. SkySafe has delivered a highly capable system built on NI SDR technology that has proven to meet both the pace of threat evolutions and form factor requirements with the USRP X310 and open source software. Contact Test Dynamics to find out more about this technology solution.