New Radar System for Flying Cars!
We have all heard of the expression, “flying under the radar” but have you ever considered that flying under the radar would be necessary in the very near future with the advent of flying cars in our cities?
New object-detection technology proliferated after World War II when radar was used for the first time in real-world scenarios. In the beginning, Military pilots had trouble seeing things at low altitudes, where buildings and hills severely would limit the range of the radar. Pilots then got used to being spotted on the new radar systems and so would hug the terrain, flying beneath the radio waves that would detect their presence.
After the second world war, the airline industry also adopted the technology and came to rely on radar detection systems for safe passage through crowded airspace but unlike the military aircraft during WW2, civilian aircraft had no need to fly under the radar.
But aviation is bracing for great changes in the very near future with the arrival of autonomous drones and flying cars. This means that the skies below 500 feet will become extremely congested and we can imagine the future will have flying vehicles in the same volumes as we have on the present road networks.
In the not so distant future, we will see flying cars whisking passengers across towns and cities all over the world. Automated flying machines carrying out a myriad of domestic tasks. As compelling as these visions are, the vehicles can’t stay invisible to the air-traffic-control systems that need to track them and keep everybody safe.
Conventional mechanical radar systems, the ones we are used to seeing—large dishes that rotate in endless circles—will still form the backbone of aviation tracking systems for the foreseeable future but new detection systems will have to be developed to help fill in the blind spots.
So Raytheon, a major U.S. defense contractor and industrial corporation with core manufacturing concentrations in weapons and military and commercial electronics, has set its sights a bit lower to use a pun.
The defence contractor has developed a low-power radar it says can fill in the gaps missed by conventional systems. Instead of having single units that sit on towers or mountaintops, spinning and scanning up to 200 miles out, Raytheon proposes distributing smaller digital systems, en masse, across the landscape. Whether this is a good idea, we would have to consider that, as it is a question for debate?
The one-square-meter units, like upright white pizza box with electronically scanned array technology that is more precise and more tunable than what’s in use now. And when spread across the terrain on cell towers, buildings, and hilltops, they should be able to track aircraft at much lower altitudes than is currently possible with conventional radar systems. Raytheon’s lead engineer on the program, Michael Dubois said,
“This ‘agile-beam’ concept allows you to redirect a pencil-like beam to follow a target, whether it’s a flying car or an airplane or a drone,”
“While conventional radar systems can only track a few targets, these systems can keep their eyes on many. You can do that with higher resolution and much faster update rates, the engineer added, since the beam never rotates away from the target.”
Active electronically scanned arrays are already in use in modern fighter jets, including the F-22 Raptor and the F-35 Lightning II, but the flying car technology should be far less expensive than the military systems.
Because the array is widely distributed across the terrain, it won’t pick up as much radio frequency interference from buildings, weather, or land masses. Units can be networked together to increase resolution and more precisely filter out that clutter. This could be key to tracking small drones and giving autonomous air vehicles enhanced situational awareness at low altitudes. Dubois. Went on to say:
“You can track aircraft, but you can also leverage it for microscale weather analysis, including 3-D wind information, and down to extremely localized tracking that could help future air vehicles as well as the general public,”
“When you get into really small areas, you can even help, for instance, hobbyists flying model rockets or airplanes or drone operators working to ensure a clear path for their own flights.”
Low-power radar networks will likely be one of a variety of solutions for future air mobility, with another key being ADS-B, the increasingly ubiquitous system that uses GPS data to automatically broadcast an aircraft’s position. ADS-B has its own limitations: To work, it must be installed on the aircraft in question. It can’t monitor weather or look for birds. So radar still matters.
In a recent demonstration for government agencies, Raytheon’s system actively tracked flights within 20 miles from a single unit, and provided detailed enough data to “guide a pilot to touchdown with surgical precision,”
The low-power radar technology, which is actually now in its third generation could be ready by mid-2019, with large-scale production following that. Raytheon promises costs similar to or better than full-size radar systems covering the same area.
Civil aviation air-traffic-control networks will be the main target for this system to start with, but the new technology could also be adopted by industry customers as well in the future. In the meantime, though, Raytheon is working to develop all the possible applications for the technology, so that, one day, flying under the radar will be nothing more than a tired cliche.