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Jam-Resistant American Radio Keeps Ukraine’s Long-Range Drones Flying

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A Ukrainian Shark reconnaissance drone resembling a small aircraft flies out over Russian lines, transmitting a stream of high-definition video. The drone searches for valuable targets like ammunition depots, air defense sites and artillery positions deep inside occupied territory. The Russians respond with electronic warfare, throwing up a wall of radio noise impenetrable to most drones. The Shark flies right on, unaffected by the jamming, thanks to its advanced Mesh Rider radio built by U.S. company Doodle Labs which allows long-range flights through intense interference.

Doodle Labs, based in Marina Del Rey, California has been working with long-range Wi-Fi since 2008, but co-CEO Ashish Parikh told me that they ended up in the military drone communications business almost by accident.

“Everything just came together in 2020,” says Parikh. “The U.S. Army and the Defense Innovation Unit were looking for small, low-cost radios for drones and we just happened to have all the right technologies.”

Industrial Origins

The key to Doodle Labs success is that they are building on a towering base of existing technology. A whole industry has grown up around the 802.11 standards of communication, which underlie WiFi and local area networking. Everything is made to the same standards, which means that companies like Doodle Labs can build their technology on top of it.

“We don’t have to keep reinventing the wheel,” says Parikh. “And 802.11 just keeps getting better.”

Traditional military radio makers build everything themselves, whereas Parikh says they can take advantage of new developments like WiFi7 which launched recently and which promises faster speeds and more robust connections. Basically, they benefit from billions of dollars of industry-wide research rather than doing it all themselves.

Doodle Labs previous work in the industrial sector included providing communications for robotic machinery like autonomous trucks in mines and mobile robots moving goods in warehouses. These tend to be very ‘messy’ environments in radio terms. Some frequencies may be full of traffic from other systems, others will be affected by radio noise and interference from industrial equipment. Communications need to be able to cope and provide a rapid, seamless link.

Parikh says there are three basic approaches to dealing with radio interference, and they use all of them. One is filtering, so that the receiver can block out everything except the exact wavelength being used to communicate. Another is using multiple bands and the third is hopping to a different band where these is no interference.

The same approaches, with some refinements, apply to the problem of countering jamming. But while military developers typically build everything themselves from the ground up with their own proprietary systems, with all the costs and development time that entails, Doodle Labs are building on existing standards. Parikh says they use commercial Qualcomm
QCOM
chips and the Linux operating system, although people had previously told him this would never work in the defence sector.

“Seeing what’s now happening, and the need to respond and move fast, all of a sudden our approach is being appreciated,” says Parikh. “I feel a sense of validation.”

The Need For Speed

The conflict in Ukraine has seen electronic warfare moving at an unprecedented pace. As the drone war escalated from a few thousand to literally millions of drones, both sides have turbocharged their efforts to jam opposing communications.

Drones like the ubiquitous kamikaze FPVs and ‘Mavik’ scouts are hard to stop, and defenders often rely on jamming. This can be a matter of breaking the control link, blocking the video feed, or jamming satellite navigation. The electronic warfare contest has turned into a cat-and-mouse game of developments where each innovation in jamming is met with a new move in countermeasures.

The pace of change seems to have found some U.S. suppliers unprepared. The Wall Street Journal reported on April 10th on poor results by Skydio drones, which although built to U.S. Army specifications, had problems in the intense jamming environment.

“Ukrainian officials have found U.S.-made drones fragile and unable to overcome Russian jamming and GPS blackout technology. At times, they couldn’t take off, complete missions or return home,” according to the WSJ. “American drone company executives say they didn’t anticipate the electronic warfare in Ukraine.”

By contrast Doodle Labs did anticipate the electronic warfare and have been winning it from the start, but only by rapid innovation.

“Resistance to jamming is the number one requirement from our defense customers at present,” says Parikh. “There are changes to the electronic warfare landscape on a monthly basis, and a rapid release cycle is required to beat the jammers.”

Ukrainian company Ukrspecsystems uses Doodle Lab’s Mesh Rider in their Shark drone which routinely carries out long-range missions. The Sky Mantis multicopter is another application, with around 100 currently operating in Ukraine.

Parikh says that jammers are constantly evolving, but they are staying a step ahead with new techniques to defeat them. The time to switch to a new frequency is now measured in milliseconds,

Some commentators suggest that one day jamming will be able to defeat all drones – the Russian recently tried this and failed with a monster jammer tank piled with electronic warfare equipment — but Parikh thinks that this will never happen simply for reasons of physics.

“A jammer has to listen for what frequencies are being used to jam them,” says Parikh. “It cannot listen and jam everything at the same time. There will always be gaps.”

And radios like Mesh Rider will always be able to exploit those gaps.

Smaller Faster Better Cheaper

Parikh describes Mesh Rider as a hybrid software-defined radio. While the theoretical, ideal software-defined radio is capable of communicating with any protocol on any wavelength, in practice it is constrained by hardware. Doodle Labs’ radio uses six different bands in a patented design claimed to be the first to offer this versatility.

Being software-defined means that upgrades can be applied quickly and easily. This is a world away from traditional military communications. The U.S. Army spent billions developing its Joint Tactical Radio System which an official report in 2012 found “demonstrated poor reliability, transmission range, and voice quality that restricted the unit’s ability to accomplish its mission.”

The JTRS program went on for many years without producing satisfactory hardware. This type of delay would not be survivable in the current conflict.

The U.S. Army’s current handheld Improved Multiband Inter/Intra Team Radios, cost $25,000 each. Like Doodle Lab’s Mesh Rider these offer a high level of encryption , but they only have a data speed of around 12 kbps, compared to megabits per second for Mesh Rider, enough to transmit high resolution video.

And crucially, the smallest version of Mesh Rider weighs less than an ounce and costs just a few hundred dollars, making it small and cheap enough for expendable drones. This efficient use of commercial off-the-shelf hardware with flexible software shows why Parikh feels their approach has been validated.

Extending Drone Reach

What really sets Doodle Labs offering apart is that they offer the capability to communicate at extended range. While many small drones can operate at 10-20 km (6-12 miles), the Shark can communicate from 80 km (50 miles) or more.

“Ukrainian engineers have done some extremely creative work with commercial off-the-shelf radios,” says Parikh. “But with how sophisticated jamming is getting, those radios can only take you so far and you need resources to develop complete solutions.”

Long-range communication means pairing highly sensitive receivers with highly efficient signal amplifiers, both technologies which require a high degree of technical expertise and where Doodle Labs has ample experience.

Looking ahead, Mesh Rider looks like a good match for Ukrolancet fixed-wing kamikaze drones with ranges in the tens of kilometres. The smallest version is also affordable enough for highly jam-resistant FPVs.

Further in the future, Parikh says mesh radio can enable new types of drone operations in which dozens of drones can operate in the same area simultaneously, overcoming current limitations. Doodle Labs is now working with a variety of customers including the U.S. Army, Rockwell and Airbus, and will be involved as a component supplier in the Pentagon’s Replicator initiative to field large numbers of small, low-cost drones.

The intense battle between communications and drone jammers is set continue. And Doodle Labs is planning to win.

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