“Sampling” technology is central to the operation of these devices and in general to the field of digital communications. Increasing the bandwidth of the signals that can be sampled while maintaining a low sampling rate would increase the capabilities of these devices.
“In digital devices, physical signals (images, sounds, etc.) are stored using a series of bits,” explains Prof. Yonina Eldar of the Faculty of Electrical Engineering. “The goal of the sampling stage is to cleverly convert a physical signal into bits of data (a series of zeros and ones) in such a way that the true underlying signal can later be recovered. This recovery is performed in the reconstruction process, in which the bits are translated back into a physical signal that can be heard or seen.”
Using only commercially available components, the team led by Prof. Eldar has built a patented prototype that far exceeds basic established limits for sampling by hundreds of percentages. It also precludes the need for processors with high computational capabilities.
Until the Technion breakthrough, it was believed that exact reconstruction of a signal with unknown spectral support using digital processing was possible only if it was sampled at a rate twice the maximum frequency of the signal (as established in 1949 by the Nyquist-Shannon sampling theorem).
Under Prof. Eldar’s supervision, graduate student Moshe Mishali set out to design a single sampling system for signals with multiple, broadband channels. Doing so successfully would make it possible to sample and reconstruct those signals perfectly at significantly lower rates than existing samplers. According to Prof. Eldar, the breakthrough was achieved by utilizing the fact that there is no broadcasting in parts of the spectrum.
“The idea is to wisely use the ‘holes’ in the spectrum in order to significantly lower the sampling rate without damaging the signal,” explains Prof. Eldar. “The difficulty lies in the fact that since we do not know where in the spectrum these holes are placed, traditional mathematical models can no longer be used to characterize and manipulate such signals. What we were able to prove is that the mere fact that we know the signal does not occupy the entire spectrum, enables reducing the sampling rate, something that was not possible until now.”
The Technion-Israel Institute of Technology is Israel's leading science and technology university. Home to the country's winners of the Nobel Prize in science, it commands a worldwide reputation for its pioneering work in nanotechnology, computer science, biotechnology, water-resource management, materials engineering, aerospace and medicine. The majority of the founders and managers of Israel's high-tech companies are alumni. Based in New York City, the American Technion Society (ATS) is the leading American organization supporting higher education in Israel, with offices around the country.
Kevin Hattori | Newswise Science News
Engineering team images tiny quasicrystals as they form
18.08.2017 | Cornell University
Astrophysicists explain the mysterious behavior of cosmic rays
18.08.2017 | Moscow Institute of Physics and Technology
Whether you call it effervescent, fizzy, or sparkling, carbonated water is making a comeback as a beverage. Aside from quenching thirst, researchers at the University of Illinois at Urbana-Champaign have discovered a new use for these "bubbly" concoctions that will have major impact on the manufacturer of the world's thinnest, flattest, and one most useful materials -- graphene.
As graphene's popularity grows as an advanced "wonder" material, the speed and quality at which it can be manufactured will be paramount. With that in mind,...
Physicists at the University of Bonn have managed to create optical hollows and more complex patterns into which the light of a Bose-Einstein condensate flows. The creation of such highly low-loss structures for light is a prerequisite for complex light circuits, such as for quantum information processing for a new generation of computers. The researchers are now presenting their results in the journal Nature Photonics.
Light particles (photons) occur as tiny, indivisible portions. Many thousands of these light portions can be merged to form a single super-photon if they are...
For the first time, scientists have shown that circular RNA is linked to brain function. When a RNA molecule called Cdr1as was deleted from the genome of mice, the animals had problems filtering out unnecessary information – like patients suffering from neuropsychiatric disorders.
While hundreds of circular RNAs (circRNAs) are abundant in mammalian brains, one big question has remained unanswered: What are they actually good for? In the...
An experimental small satellite has successfully collected and delivered data on a key measurement for predicting changes in Earth's climate.
The Radiometer Assessment using Vertically Aligned Nanotubes (RAVAN) CubeSat was launched into low-Earth orbit on Nov. 11, 2016, in order to test new...
A study led by scientists of the Max Planck Institute for the Structure and Dynamics of Matter (MPSD) at the Center for Free-Electron Laser Science in Hamburg presents evidence of the coexistence of superconductivity and “charge-density-waves” in compounds of the poorly-studied family of bismuthates. This observation opens up new perspectives for a deeper understanding of the phenomenon of high-temperature superconductivity, a topic which is at the core of condensed matter research since more than 30 years. The paper by Nicoletti et al has been published in the PNAS.
Since the beginning of the 20th century, superconductivity had been observed in some metals at temperatures only a few degrees above the absolute zero (minus...
16.08.2017 | Event News
04.08.2017 | Event News
26.07.2017 | Event News
21.08.2017 | Materials Sciences
21.08.2017 | Health and Medicine
21.08.2017 | Materials Sciences