Tiny ADS-B transceiver could provide high-traffic drone solution

By Patrick C. Miller | February 02, 2017

A dime-sized ADS-B transponder that can fit in a small unmanned aircraft system (UAS) has been demonstrated by uAvionix Corp. as a potential solution to dealing with high levels of drone traffic in the future.

While the technology could be used for UAS traffic management, Christian Ramsey, uAvionix vice president of business development, said that’s not the primary purpose for which it was developed.

The transceiver prototype transmits at 01. to .25 Watts, enabling aircraft equipped with ADS-B “IN” avionics to see at UAS from one to 10 miles away. The idea, Ramsey said, is not to have every UAS in the air show up on an air traffic controller’s screen, but to give manned and unmanned aircraft the ability to see and avoid each other.

“We want to get across the point that that there’s a standard that needs to be developed to allow these low-power systems to operate,” he explained. “We don’t have to shout so loud. This can be done more cheaply when compared to an air traffic control system.”

The transceiver is small enough to integrate directly into professional and consumer-level drones. The company is working with the Federal Aviation Administration (FAA) and other partners under a Collaborative Research and Development Agreement (CRDA) to test the unit, along with other uAvionix products.

Ramsey referenced a study published this year by the MITRE Corp. Center for Advanced Aviation System Development (CAASD) which imagines a future world of very high traffic densities of drones operating with ADS-B onboard. The study explored the implications of that scenario.

“We developed this product to show the world the art of the possible,” said Paul Beard, uAvionix CEO. “We can’t yet sell this device because the standards that were developed for ADS-B did not take into account the value of air-to-air ADS-B communications between small drones or between small drones and manned aircraft.

“It’s literally not legal to transmit at these low power outputs,” he continued. “We aim to lead the discussion and development of those standards, and will work with any regulatory body to do so.”

Ramsey said the Mitre study suggests that there is a nominal transmission power output between .01 and .1 Watts that—when coupled with limited drone traffic densities—can result in a compatible operation with the system as a whole.

“We need our regulators to identify this as an opportunity for a quick standard that can be developed, released, and required on those most risky of drone operations,” Ramsey wrote in a blog on the uAvionix website.