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Professor Bahram Jalali sits in his lab which recently revolutionized the way scientists analyze

A breakthrough device recently created by UCLA researchers is capable of converting electrical signals 50 times faster than the best commercially available one, and has promising implications for more efficient communication systems and for defense against high-powered electromagnetic bombs.

After eight years of work, Professor Bahram Jalali presented a modified form of a conventional digitizer at the 2005 American Physical Society’s March meeting in the Los Angeles Convention Center, which led to immediate interest in the development and arrangements for further research.

“As electronic devices become smaller and faster, they also become more susceptible to outside interference,” Jalali said.

“In order to make equipment more robust, to shield it from electromagnetic attacks, you first have to understand what kind of signals you’re dealing with. Because the pulses we’re talking about are one-time events and are extremely fast, their capture and analysis eludes conventional digitizers. That’s exactly what our technique allows,” he added.

The UCLA team found a method to increase the performance of an electronic digitizer by using optics to process the signals before digitizing them. In other words, it allows them to analyze fast signals by slowing them down first.

The technique may allow physicists to capture and analyze particle interactions which have important implications in biochemistry and biology.

RadiaBeam Technologies LLC of Los Angeles already has entered into licensing negotiations with UCLA and plans to produce a laboratory tool for high-energy physics research, said Salime Boucher, president of RadiaBeam, according to a UCLA press release.

“We see a market for this breakthrough with research laboratories involved in ultrafast phenomena and transient events, as well as for future applications by engineering and technology companies in the communication, chemical engineering and life science sectors,” Boucher said.

The UCLA researchers have also shown that time-elasticity can be used to perform time compression and time reversal, which can be applied to radar systems.

Another realm affected by the development is astronomy. There is increasing ability to observe gamma rays given off by entities such as massive black holes and pulsars left over from supernova explosions.

Digitizers analyze real world analogs by converting these signals using complex algorithms into discrete signals to be analyzed.

A continuous real-time signal cannot be held long enough to record and convert into data. Rather, signals are collected in discrete values and information in between these samples is left out.

To distinguish between all signal frequency components and to reconstruct a signal accurately, one must sample faster than twice the frequency of the highest frequency component. But sampling fast for a long time means researchers will have a lot of samples – and lots of samples means lots of computation, for which researchers generally don’t have time.

To help rectify these errors in sampling and to produce a signal as close to the first as possible, previous research in this area has concentrated on making digitizers compute faster. But the UCLA team has slowed them down.

“Imagine you have a flat rubber band and you draw an arrow on it. The arrow’s length reflects the duration of the event. When you stretch the rubber band, the arrow is elongated, meaning that the event now occurs over a longer time – in other words, the event is slowed down in time,” Jalali said.

An optical time dilation processor is used to stretch the time in which the event occurs. Only after the event is slowed does sampling and conversion of this signal into electrical data occur. The time-stretch technique appears to be the most promising in enabling ultrawideband analog-to-digital conversion of fast waveforms to be digitized at pico-second intervals.

An additional advantage of the time-stretch digitizer is that it would be cost effective to produce. The recent advances in silicon photonics make it possible to integrate the entire digitizer on a silicon chip, leading to a compact and low-cost solution.