Vasilyev Authors Article to Explain Research in Science Magazine
Wednesday, December 16, 2015
Michael Vasilyev, a Fellow of The Optical Society and an electrical engineering professor at The University of Texas at Arlington, authored an article in the Dec. 11, 2015, issue of Science Magazine. In it, he provides context and explains concepts so that readers can understand the work contained in a paper authored by researchers at the University of California at San Diego that is also published in the issue.
The article, entitled “Matched Filtering of Ultrashort Pulses,” introduced the publication of a paper on findings by Stojan Radic’s research group.
“The experiment by Professor Radic’s group uses nonlinear-optical signal processing to recover a very short and weak electrical pulse hidden in a large amount of noise. One can view this as using optical means to build a matched filter for optimum detection of an electrical pulse. Since I also work with nonlinear-optical signal processing and matched filtering, although of a different type, I provided an introduction that put the UCSD work in the context of optimal detection and explained the basic concepts needed to understand their work,” Vasilyev said.
A matched filter is the front end of an optimal signal detector, which perfectly fits only the signal of interest. Any change in the shape of the expected signal requires a change in the shape of the filter, so it is important to have a filter that can be dynamically reconfigured based on the shape of the signal.
Vasilyev was selected to write his introductory article because he has done extensive research using matched filtering. Although he is not working with the same type of filters, he uses matched filtering to detect quantum states. It is very important to be able to match the detector being used to the signals that may be received, because if they are not perfectly matched, the reception quality will be poor and the signal will be buried in the noise. In his article, Vasilyev describes how the UCSD researchers have enabled reconfigurable matched filtering of ultrashort signals that are near the limits of today’s electronics.
“This experiment builds upon the UCSD group’s advances in the development of spectral cloning, where many copies of a signal can be made with very little added noise, and of high-quality optical combs, which are light beams consisting of periodically spaced discrete frequencies. The combination of these two technologies has enabled the researchers to accurately measure the amplitudes and phases of all of the ultrashort signal’s spectral components with relatively low-speed electronics and feed this information into a digital signal processor to synthesize the matched filter and detect the absence or presence of the signal pulse,” Vasilyev said.
Vasilyev’s work is just one example of Data-Driven Discovery, one pillar of UTA’s Strategic Plan | 2020. He, and others in the College of Engineering are working to ensure fast, secure transmission of information. Learn more at uta.edu/engineering.