Drone Challenge Rides Soft Radio

　　Eight teams will compete here later this month to fly drones using software programmed radios. The weeklong hackfest aims to raise the profile of software-defined radio (SDR) and explore new possibilities for it in military and commercials markets.

　　The event was organized by Tom Rondeau, program manager in the microsystems department of the Defense Advanced Research Projects Agency. Before joining DARPA last year, Rondeau spent six years leading GNU Radio, an open source framework for SDR.

　　“A software radio can be cellular, Wi-Fi, anything based on how you program it — it’s all math and numerical processing,” Rondeau said. He described GNU Radio as “a domain specific language for signal processing to develop demodulators, filters and transmitters — it’s a pretty complete tool set used by R&D groups all around the world.”

　　Outcomes of the hackfest may vary from helping soldiers jam enemy communications to opening airwaves for the billions of wireless devices expected on the emerging Internet of Things.

　　“Get enough drones tougher and there’s a spectrum crunch,” said Rondeau. “We’ve observed swarms with off-the-shelf radios that can only sustain 50 drones in a geographical area because they run out of spectrum, so in 10-15 years if we’re going to have a trillion wireless devices we’ll need something smarter than another Wi-Fi chip set,” he said.

　　“The teams are prepped to think about the link between ground control and drones as software definable…so they may find new modes of operation you can only think of working at computer speed...think of the drone as a programmable extension of the computer,” he explained.

　　“Changes in how we use drones may come out of this, but while the event is focused on drones, my intent is to get people interested in software radio, programming spectrum and applying new knowledge about it,” he added.

　　So far, SDR has lacked strong commercial drivers. Advances in LTE and upcoming 5G cellular networks help ease the spectrum crunch, mainly by reducing cell sizes.

　　However military planners “don’t have the luxury of using a standard… so we are adapting and manipulating spectrum to avoid interception and jamming,” he said. Thus, the Pentagon maintains a tiger team that uses drones to manipulate spectrum based on GNU Radio tools, he added.

　　Competing teams at the hackfest will represent the defense industry, Silicon Valley startups and academics. They come from Aerospace Corp., Assured Information Security, Hacker DoJo, a makerspace in New York City, Raytheon BBN Technologies, the University of California and Southern Methodist University.

　　Speakers at the weeklong event are equally diverse, ranging from science fiction writer Cory Doctorow to a privacy lawyer, a representative of the Linux Foundation, veteran hackers and policy experts.

　　“The FCC loves SDR. They don’t know how to regulate it, but they want to figure it out…The FAA is pro-drone but they are moving cautiously,” he said.

　　Separately, Rondeau runs a program at DARPA that hopes to explore ways to bring SDR to embedded systems.

　　“Software radio hasn’t proliferated because its compute- and power-hungry, so we’re looking to build low power processors for use near the sensor edge of the IoT,” he said, noting the Domain Specific SoC project is not specific or limited to SDR.