Drones get bad cell service, but an old ambulance will help

Researchers at Carnegie Mellon University are building a model of cell coverage up in the air

A view of Carnegie Mellon University's Crossmobile seen from a drone during a field test.

A view of Carnegie Mellon University's Crossmobile seen from a drone during a field test.

In the race to get drones into the sky and zipping across cities delivering packages and snapping photos, cellular networks are quickly emerging as the preferred way of keeping them in touch with the ground.

But researchers are finding that getting a reliable signal a hundred meters up in the air isn't as easy as it might seem, and that could present a challenge for companies like Amazon, which want to fly drones over distances greater than WiFi or similar technology allows and maintain contact with the craft during their flight.

The problem is that cellular networks are designed to provide coverage at ground level -- where the customers are -- and not up in the air. Take a look at any cellular base station antenna and you'll notice its antennas points down, not horizontally or up.

Trying to predict the coverage of a base station is complicated, but that's where researchers at Carnegie Mellon University's Silicon Valley campus come in.

Using a converted ambulance and drones of their own, they have been investigating how cellular signals travel through the air and reflect off the ground and other objects to try to build an accurate model of coverage.

(See inside the ambulance in this video.)

"We've built into this old ambulance, a full cellular network," said Bob Iannucci, leader of the CyLab Mobility Research Center at the campus located at NASA's Ames Research Park at Moffett Field, California. "We have the ability to go anywhere, set up a big antenna, create what we call a cellular bubble of coverage, and connect that via satellite."

The group first started taking measurements the old way, by walking around, but then decided that a phone strapped to the bottom of a quadcopter would be easier.

"We discovered that the signal up there is pretty different from what you might imagine," said Iannucci, who was previously chief technology officer of Nokia and head of the company's research center.

So now, several times a year, Iannucci and his students travel to a remote location armed with an FCC license allowing them to operate an experimental radio system. They raise a pneumatic mast and antenna that have been fitted to the ambulance and power up the equipment. A rack of servers and radio gear inside the ambulance generates the cellular signal and a satellite antenna on the roof of the vehicle provides an Internet connection.

Students then climb up onto the roof of the ambulance and fly their drones, all the time capturing information about the cellular signal.

Recently, the group partnered with the U.S. Geological Survey to get detailed laser scans of the surrounding terrain. The hope is that the radio measurements and terrain map will lead to software than can more accurately simulate cell coverage in any given location.

"People think that 'if I can see the antenna, the signal must be great,' but that's not really true," said Iannucci.

The team didn't set out to map cellular coverage for drones, but the work could be important as regulatory hurdles are cleared for greater use of drones by the public and companies.

Martyn Williams covers mobile telecoms, Silicon Valley and general technology breaking news for The IDG News Service. Follow Martyn on Twitter at @martyn_williams. Martyn's e-mail address is martyn_williams@idg.com

Join the Good Gear Guide newsletter!

Error: Please check your email address.

Tags NASArobotics

Our Back to Business guide highlights the best products for you to boost your productivity at home, on the road, at the office, or in the classroom.

Keep up with the latest tech news, reviews and previews by subscribing to the Good Gear Guide newsletter.

Martyn Williams

IDG News Service
Show Comments

Most Popular Reviews

Latest News Articles

Resources

PCW Evaluation Team

Azadeh Williams

HP OfficeJet Pro 8730

A smarter way to print for busy small business owners, combining speedy printing with scanning and copying, making it easier to produce high quality documents and images at a touch of a button.

Andrew Grant

HP OfficeJet Pro 8730

I've had a multifunction printer in the office going on 10 years now. It was a neat bit of kit back in the day -- print, copy, scan, fax -- when printing over WiFi felt a bit like magic. It’s seen better days though and an upgrade’s well overdue. This HP OfficeJet Pro 8730 looks like it ticks all the same boxes: print, copy, scan, and fax. (Really? Does anyone fax anything any more? I guess it's good to know the facility’s there, just in case.) Printing over WiFi is more-or- less standard these days.

Ed Dawson

HP OfficeJet Pro 8730

As a freelance writer who is always on the go, I like my technology to be both efficient and effective so I can do my job well. The HP OfficeJet Pro 8730 Inkjet Printer ticks all the boxes in terms of form factor, performance and user interface.

Michael Hargreaves

Windows 10 for Business / Dell XPS 13

I’d happily recommend this touchscreen laptop and Windows 10 as a great way to get serious work done at a desk or on the road.

Aysha Strobbe

Windows 10 / HP Spectre x360

Ultimately, I think the Windows 10 environment is excellent for me as it caters for so many different uses. The inclusion of the Xbox app is also great for when you need some downtime too!

Mark Escubio

Windows 10 / Lenovo Yoga 910

For me, the Xbox Play Anywhere is a great new feature as it allows you to play your current Xbox games with higher resolutions and better graphics without forking out extra cash for another copy. Although available titles are still scarce, but I’m sure it will grow in time.

Featured Content

Latest Jobs

Don’t have an account? Sign up here

Don't have an account? Sign up now

Forgot password?