Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Purdue engineers use ’shaped’ laser pulses in ’ultra-wideband’ research

06.04.2005


Engineers at Purdue University have developed a technique that could result in more accurate "ultra-wideband" radio signals for ground-penetrating radar, radio communications and imaging systems designed to see through walls.

The researchers first create laser pulses with specific "shapes," which precisely characterize the changing intensity of light from the beginning to end of each pulse. The pulses are then converted into electrical signals for various applications.

By controlling the shapes of laser pulses, the researchers are able to adjust the frequencies of the resulting radio signals and to produce signals with higher frequencies than are otherwise possible. Shorter signals make it easier to screen out interference and enhance image resolution, promising to improve the accuracy of systems used to detect landmines and other underground objects and for newly emerging devices that can look through walls and see what’s on the other side. "You want the best spatial resolution possible if you have two items buried close to one another," said Jason McKinney, a visiting assistant professor of electrical and computer engineering at Purdue. "If your pulse is too long, you get a combined reflection from both items back, but if your pulse is short enough, you get a separate reflection from each."



A similar situation arises in wireless communications. When radio signals are transmitted from one antenna to another, some travel directly to the second antenna while others bounce off of buildings and other objects along the way, causing "noise," or interference. By shaping the laser pulses so they are "narrow," shorter electronic signals can be created. The shorter the signals, the easier it is to pick them out from the noisy, interfering signals by the time they arrive at the receiving end of the transmission. The researchers’ technique will be detailed in a paper to appear in the April issue of IEEE Microwave and Wireless Components Letters, a journal published by the Institute of Electrical and Electronics Engineers. The paper was written by Ingrid S. Lin, a Purdue doctoral student, McKinney and Andrew Weiner, a professor of electrical and computer engineering.

Ultra-wideband technology, commonly referred to as UWB, has numerous potential applications, including high-speed handheld wireless communications for consumer electronics, radar systems in cars that might be used to prevent collisions and the development of "personal area networks," or wireless networks linking computer equipment, personal digital assistants and other devices within a person’s workspace.

While commercially available electronic devices produce a fixed set of wideband frequencies, the Purdue team is able to adjust the shapes of optical pulses and the resulting electrical signal, which means more precisely controlled ultra-wideband frequencies can be produced. "The main innovation is the ability to define what we want," McKinney said. "We’re able to say, ’Here is what I want, give it to me, and the system produces the desired signal.’"

The innovation could have laboratory applications in testing and research and in the development of ultra-wideband and wireless radio systems. Each laser pulse lasts about 300 femtoseconds, or three-tenths of a trillionth of a second. These pulses are processed using "optical arbitrary waveform technology" pioneered by Purdue researchers led by Weiner, which results in a three-nanosecond laser pulse. "There are commercial boxes that generate pulsed electrical signals, but the user has no control over the shape of these signals," McKinney said. "Because we can create desired shapes of pulsed light, we are able to create electrical signals that you can’t buy a commercial box to make. The pulse is designed to produce the desired electrical ’waveform,’ or a shaped electrical signal that evolves over time in a user-defined way."

The radio-frequency signal is obtained after a device converts the laser pulse into a radio signal for radar and wireless communications. "Our goal is to improve radio frequency communications, impulsive radar and other applications in the blossoming area of ultra-wideband radio frequency systems," McKinney said.

The work has been funded by the U.S. Army Research Office.

Writer: Emil Venere, (765) 494-4709, venere@purdue.edu

Sources: Jason D. McKinney, (765) 494-3454, mckinnjd@purdue.edu

Andrew M. Weiner, (765)494-5574, amw@ecn.purdue.edu

Purdue News Service: (765) 494-2096; purduenews@purdue.edu

Emil Venere | EurekAlert!
Further information:
http://www.purdue.edu

More articles from Power and Electrical Engineering:

nachricht Researchers use light to remotely control curvature of plastics
23.03.2017 | North Carolina State University

nachricht TU Graz researchers show that enzyme function inhibits battery ageing
21.03.2017 | Technische Universität Graz

All articles from Power and Electrical Engineering >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: A Challenging European Research Project to Develop New Tiny Microscopes

The Institute of Semiconductor Technology and the Institute of Physical and Theoretical Chemistry, both members of the Laboratory for Emerging Nanometrology (LENA), at Technische Universität Braunschweig are partners in a new European research project entitled ChipScope, which aims to develop a completely new and extremely small optical microscope capable of observing the interior of living cells in real time. A consortium of 7 partners from 5 countries will tackle this issue with very ambitious objectives during a four-year research program.

To demonstrate the usefulness of this new scientific tool, at the end of the project the developed chip-sized microscope will be used to observe in real-time...

Im Focus: Giant Magnetic Fields in the Universe

Astronomers from Bonn and Tautenburg in Thuringia (Germany) used the 100-m radio telescope at Effelsberg to observe several galaxy clusters. At the edges of these large accumulations of dark matter, stellar systems (galaxies), hot gas, and charged particles, they found magnetic fields that are exceptionally ordered over distances of many million light years. This makes them the most extended magnetic fields in the universe known so far.

The results will be published on March 22 in the journal „Astronomy & Astrophysics“.

Galaxy clusters are the largest gravitationally bound structures in the universe. With a typical extent of about 10 million light years, i.e. 100 times the...

Im Focus: Tracing down linear ubiquitination

Researchers at the Goethe University Frankfurt, together with partners from the University of Tübingen in Germany and Queen Mary University as well as Francis Crick Institute from London (UK) have developed a novel technology to decipher the secret ubiquitin code.

Ubiquitin is a small protein that can be linked to other cellular proteins, thereby controlling and modulating their functions. The attachment occurs in many...

Im Focus: Perovskite edges can be tuned for optoelectronic performance

Layered 2D material improves efficiency for solar cells and LEDs

In the eternal search for next generation high-efficiency solar cells and LEDs, scientists at Los Alamos National Laboratory and their partners are creating...

Im Focus: Polymer-coated silicon nanosheets as alternative to graphene: A perfect team for nanoelectronics

Silicon nanosheets are thin, two-dimensional layers with exceptional optoelectronic properties very similar to those of graphene. Albeit, the nanosheets are less stable. Now researchers at the Technical University of Munich (TUM) have, for the first time ever, produced a composite material combining silicon nanosheets and a polymer that is both UV-resistant and easy to process. This brings the scientists a significant step closer to industrial applications like flexible displays and photosensors.

Silicon nanosheets are thin, two-dimensional layers with exceptional optoelectronic properties very similar to those of graphene. Albeit, the nanosheets are...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

International Land Use Symposium ILUS 2017: Call for Abstracts and Registration open

20.03.2017 | Event News

CONNECT 2017: International congress on connective tissue

14.03.2017 | Event News

ICTM Conference: Turbine Construction between Big Data and Additive Manufacturing

07.03.2017 | Event News

 
Latest News

Periodic ventilation keeps more pollen out than tilted-open windows

29.03.2017 | Health and Medicine

Researchers discover dust plays prominent role in nutrients of mountain forest ecoystems

29.03.2017 | Earth Sciences

OLED production facility from a single source

29.03.2017 | Trade Fair News

VideoLinks
B2B-VideoLinks
More VideoLinks >>>