“The U.S. government has noted that broadband wireless access technologies are a key foundation for economic growth, job creation, global competitiveness, and a better way of life," explained Claudio da Silva, an assistant professor in Virginia Tech’s Bradley Department of Electrical and Computer Engineering. He was referring to a recent report by the Federal Communications Commission on the need to ensure all Americans have access to broadband capability.
These spectrum-sensing technologies are envisioned to support high speed internet in rural areas, enable the creation of super Wi-Fi networks, and support the implementation of smart grid technologies. However, implementation of these technologies is seen as the "the greatest infrastructure challenge of the 21st century," according to the commission’s report.
A major key to solving this challenge is in the design of wireless systems that more efficiently use the limited radio spectrum resources, said da Silva. “As a means to achieve this goal, the U.S. government, through the Federal Communications Commission, has recently finalized rules to make the unused spectrum in the television band available to unlicensed broadband wireless systems. In these systems, devices first identify underutilized spectrum with the use of spectrum databases and/or spectrum sensing and then, following pre-defined rules, dynamically access the “best” frequency bands on an opportunistic and non-interfering basis.”
"The U.S. government has plans to release even more spectrum for unlicensed broadband wireless access," added da Silva. "While sensing is not a requirement for television band access, the Federal Communications Commission is encouraging the continued development of spectrum sensing techniques for potential use in these new bands."
“InterDigital’s advanced wireless technology development efforts compliment this work at Virginia Tech,” added James J. Nolan, InterDigital’s executive vice-president of research and development. ”We see the evolution of wireless systems to dynamic spectrum management technologies as being key to solving the looming bandwidth supply-demand gap by more efficiently leveraging lightly used spectrum. These cognitive radio technologies are an integral part of our holistic bandwidth management strategy, and we have invested significantly in this area of research.”
During the first phase of the study, "by exploiting location-dependent signal propagation characteristics, we have developed efficient sensing algorithms that enable a set of devices to work together to determine spectrum opportunities", said William Headley, of Ringgold, Va., one of the Ph.D. students working on this project.
For the second year of the study, the focus is changing to the design of spectrum sensing algorithms that are robust to both man-made noise and severe multipath fading. "The vast majority of sensing algorithms were developed for channels in which the noise is a Gaussian process," said Gautham Chavali, of Blacksburg, Va., the second Ph.D. student working on this project. “However, experimental studies have shown that the noise that appears in most radio channels is highly non-Gaussian,” Chavali added.
"Man-made noise, which arises from incidental radiation of a wide range of electrical devices, for example, is partially responsible for this occurrence," Chavali said. In addition, the algorithms to be designed will not rely on the common, but impractical, assumption of perfect synchronization and equalization by the radio front-end, which is an important concern when dealing with realistic multipath fading channels, such as indoor environments.
InterDigital develops advanced wireless technologies that are at the core of mobile devices, networks, and services worldwide. Using a holistic approach to addressing the bandwidth crunch, the company is developing innovations in spectrum optimization, cross-network connectivity and mobility, and intelligent data. InterDigital has provided funding for this 30-month research project, including the donation of state of the art laboratory equipment that will support different wireless projects at Virginia Tech.
Lynn A. Nystrom | Newswise Science News
Smart Data Transformation – Surfing the Big Wave
02.12.2016 | Fraunhofer-Institut für Angewandte Informationstechnik FIT
Climate change could outpace EPA Lake Champlain protections
18.11.2016 | University of Vermont
In recent years, lasers with ultrashort pulses (USP) down to the femtosecond range have become established on an industrial scale. They could advance some applications with the much-lauded “cold ablation” – if that meant they would then achieve more throughput. A new generation of process engineering that will address this issue in particular will be discussed at the “4th UKP Workshop – Ultrafast Laser Technology” in April 2017.
Even back in the 1990s, scientists were comparing materials processing with nanosecond, picosecond and femtosesecond pulses. The result was surprising:...
Have you ever wondered how you see the world? Vision is about photons of light, which are packets of energy, interacting with the atoms or molecules in what...
A multi-institutional research collaboration has created a novel approach for fabricating three-dimensional micro-optics through the shape-defined formation of porous silicon (PSi), with broad impacts in integrated optoelectronics, imaging, and photovoltaics.
Working with colleagues at Stanford and The Dow Chemical Company, researchers at the University of Illinois at Urbana-Champaign fabricated 3-D birefringent...
In experiments with magnetic atoms conducted at extremely low temperatures, scientists have demonstrated a unique phase of matter: The atoms form a new type of quantum liquid or quantum droplet state. These so called quantum droplets may preserve their form in absence of external confinement because of quantum effects. The joint team of experimental physicists from Innsbruck and theoretical physicists from Hannover report on their findings in the journal Physical Review X.
“Our Quantum droplets are in the gas phase but they still drop like a rock,” explains experimental physicist Francesca Ferlaino when talking about the...
The Max Planck Institute for Physics (MPP) is opening up a new research field. A workshop from November 21 - 22, 2016 will mark the start of activities for an innovative axion experiment. Axions are still only purely hypothetical particles. Their detection could solve two fundamental problems in particle physics: What dark matter consists of and why it has not yet been possible to directly observe a CP violation for the strong interaction.
The “MADMAX” project is the MPP’s commitment to axion research. Axions are so far only a theoretical prediction and are difficult to detect: on the one hand,...
16.11.2016 | Event News
01.11.2016 | Event News
14.10.2016 | Event News
08.12.2016 | Life Sciences
08.12.2016 | Physics and Astronomy
08.12.2016 | Materials Sciences