A new type of air-traffic radar can spot small quadcopters at distances of up to eight kilometres away, which could offer a solution to plug the technology gap created by the rise of unmanned airborne devices.
The holographic radar developed by Cambridge-based firm Aveillant uses a sophisticated set of algorithms to sieve through radar returns to provide the most detailed picture of the airspace.
During a series of tests, underway since the end of 2014, the technology has proved that it can identify a drone as small as 35cm wide and 19cm tall at a distance of almost 7.5km in only a few seconds.
The inability to spot such remotely operated devices is the major weakness of conventional air-traffic radar technology. In an incident reported last year, a remotely operated quadcopter came within a distance of only seven metres from a passenger jet landing at London's Heathrow Airport. The incident, unobserved by air-traffic controllers, was only reported by the pilot of the affected plane.
“With the recent increase in public drone activity, including drone flights over sensitive sites such as nuclear power stations and government buildings, and incidents of proximity with civil airliners, the world is understandably concerned about the potential risks that this accessible technology presents,” said Rob Abbott, Aviation Director at Aveillant.
“Any increase in this sort of airspace activity requires rapid and focused industry development in order to have solutions in place before further risks materialise. The industry needs a surveillance solution capable of continuous, intelligent interrogation of the airspace, providing 100 per cent surveillance of every target, including drones.”
Conventional air-traffic radars, designed in the pre-drone era, focus on detecting large aircraft across distances of several hundred kilometres, not small drones flying much closer by.
"[Existing radar systems] are not designed to look for something like a quadcopter or a small one or two-metre fixed-winged aircraft, which could comfortably fly at 700ft,” said Peter Doig, a defence technology consultant at Plextek Consulting, a firm developing a similar system to that of Aveillant. “These UAVs have very small radar cross-sections as they are predominantly made of non-metallic materials, such as plastics, which don't have a very big return from radar."
Aveillant’s holographic radar can also retain data for future traceability in case in-depth investigation is needed.