A New Laser-Based Radar System Will Help Track the Next Missing Plane

Light-based radar is more accurate and has a longer range than traditional radio waves or microwaves.

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Mar 19 2014, 6:30pm
The team tests the new radar in Italy. Image: Antonella Bogoni

Researchers in Italy have just developed "the next generation of radar," which could help track planes more closely. It comes at a time when tracking planes is a hot issue, after Malaysian Airlines Flight 370 went mysteriously missing from radar.

More than a week after the flight disappeared somewhere off the coast of Malaysia, officials still have no idea what happened to it or where it went. Recent reports suggest that radar in Thailand may have tracked the plane, but so far, all we know is that the plane eventually fell off all of the radars that were keeping tabs on it. As we explained shortly after the flight’s disappearance, radar has a limited range, and there are plenty of dead zones over certain parts of the ocean.

That’s because the radar technology we have hasn’t greatly changed since it was developed in the lead-up to and perfected during World War II. Electronics have gotten better and systems have become more sophisticated, but the basic, underlying technology—radio waves or microwaves go out, radio waves or microwaves bounce back in to an electronically-powered tower—has remained essentially the same.

That could soon change. A research team at Italy’s National Inter-University Consortium for Telecommunications has designed and tested a radar system based almost entirely on lasers, which could give us a longer range and increased accuracy when tracking airplanes.

Image: Malaysian Government

The photonics-based system was described in a study published Wednesday in Nature, and military experts say it could quickly become the new standard if early tests can be improved upon. The system used a “mode-locked laser” that can stay trained on an airplane. This allows the plane’s movement across a radar screen to be much less jittery, because the radar is receiving more frequent updates about its position.

The light-based system can also remove much of current radar’s reliance on electronics, which could have potentially been useful if Flight 370 experienced an electrical fire, as some have suggested.

The new system has “phase noise and timing jitter that are approximately half those of state-of-the-art conventional RF synthesizers,” according to Jason McKinney, a photonics researcher at the U.S. Naval Research Lab. “Their work shows that such techniques may indeed provide capability for next-generation radar systems.”

Here's a schematic of how the whole thing works. Image: Nature

In a field test, lead researcher Paolo Ghelfi tracked a series of planes taking off from a local airport and then compared his results to those on a public database and found “excellent agreement” between the two data sets.

More importantly, Ghelfi says that laser-based airplane radar can “increase the radar coverage,” over traditional radar, a capability we desperately need and one that may have come in handy in the case of Flight 370. Ghelfi wouldn’t speculate as to whether his radar system would have been able to track the missing plane because there is still much we don’t know about what happened, but says that his system offers more bandwidth, more flexibility, the potential to shift to “fully digital” radars, and higher precision than existing radar. 

We’ll never know if a photonics-based radar could have tracked Flight 370, but, if they ever become common, we might have more to go on if a similar mystery occurs in the future.