Featured Research

from universities, journals, and other organizations

Low Power, Highly Reliable, Wireless, Infrared Local Area Networks Demonstrated

Date:
July 25, 2001
Source:
Penn State
Summary:
Penn State engineers have shown that broadband, wireless, indoor, local area communication networks that rely on non-line-of-sight infrared (IR) signal transmission can offer low error rates as well as safe, low – below one Watt – power levels.

University Park, Pa. --- Penn State engineers have shown that broadband, wireless, indoor, local area communication networks that rely on non-line-of-sight infrared (IR) signal transmission can offer low error rates as well as safe, low – below one Watt – power levels. Dr. Mohsen Kavehrad, professor of electrical engineering and holder of the W. L. Weiss (AMERITECH) chair, says, "Line-of-sight or point-to-point infrared signal transmission, which is used, for example, in television remote controls, is highly efficient at low power levels but suffers from the need for alignment between the transmitter and receiver. If someone ‘shadows' or blocks the remote control beam while you're trying to change the channel, the signal can't get through.

Related Articles


"On the other hand, non-line-of-sight transmission, which uses a broad diffuse beam, suffers less from shadowing but usually forfeits the power efficiency, broadband and low error rate values that infrared transmission can offer." Now, however, Kavehrad and his colleagues at Penn State's Center for Information and Communications Technology Research have developed a new link design that uses a multi-beam transmitter with a narrow field of view receiver. The system has a bit-error rate of only one error per billion bits and uses milliwatt transmitted power levels. Kavehrad says, "This error rate is unmatched considering the offered transmission capacity." The Penn State researcher detailed the system Sunday, July 22, at the Fifth World Multi-Conference on Systemics, Cybernetics and Informatics SCI 2001 meeting in Orlando, Florida. His paper, "Some Recent Advances in Indoor Broadband Infrared Wireless Communications," is co-authored by Dr. Svetla Jivkova, research associate. To use the Penn State signaling scheme, for example, to form a local area network for a group of computers in a room, each machine is equipped with a low power infrared source and a holographic beam splitter. The original low power beam is separated into several narrow beams, which strike the ceiling and walls at points that form an invisible grid throughout the entire volume of the room. Because the beams are also reflected at each of the strike points, they can be used to send or receive information. Since the beams created by the splitter are narrow, narrow field-of-view receivers are used. Using a narrow field of view receiver makes it easier to filter out noise. In addition, receivers consisting of more than one element can insure continued coverage when some of the transmitter beams are blocked. Kavehrad notes, "Others have attempted to develop local area networks with radio frequencies. However, indoors, radio frequencies can pose a radiation hazard."

"Infrared signals, on the other hand, pose no such hazard, especially at the low powers used by our system. However, since the sun is an infrared emitter, as well as fluorescent and incandescent bulbs, light coming in through windows or from artificial lighting can add background noise to the system. This noise, to some extent, can be filtered at the receivers." The Penn State team developed a framework for computer simulation under which properties of room, transmitter and receiver are quantified. Using the simulation results, they showed that the system has a bit-error rate of only one error per billion bits in 99 percent of the coverage area at bit rates up to a few hundred megabits per second. In addition, the system uses transmitted power levels well below one Watt.

The wireless infrared communication system is being patented by the University. The research was supported by grants from the National Science Foundation and the Pennsylvania technology development program known as the Pittsburgh Digital Greenhouse.


Story Source:

The above story is based on materials provided by Penn State. Note: Materials may be edited for content and length.


Cite This Page:

Penn State. "Low Power, Highly Reliable, Wireless, Infrared Local Area Networks Demonstrated." ScienceDaily. ScienceDaily, 25 July 2001. <www.sciencedaily.com/releases/2001/07/010725081349.htm>.
Penn State. (2001, July 25). Low Power, Highly Reliable, Wireless, Infrared Local Area Networks Demonstrated. ScienceDaily. Retrieved December 21, 2014 from www.sciencedaily.com/releases/2001/07/010725081349.htm
Penn State. "Low Power, Highly Reliable, Wireless, Infrared Local Area Networks Demonstrated." ScienceDaily. www.sciencedaily.com/releases/2001/07/010725081349.htm (accessed December 21, 2014).

Share This


More From ScienceDaily



More Matter & Energy News

Sunday, December 21, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Building Google Into Cars

Building Google Into Cars

Reuters - Business Video Online (Dec. 19, 2014) Google's next Android version could become the standard that'll power your vehicle's entertainment and navigation features, Reuters has learned. Fred Katayama reports. Video provided by Reuters
Powered by NewsLook.com
AP Review: Nikon D750 and GoPro Hero 4

AP Review: Nikon D750 and GoPro Hero 4

AP (Dec. 19, 2014) What to buy an experienced photographer or video shooter? There is some strong gear on the market from Nikon and GoPro. The AP's Ron Harris takes a closer look. (Dec. 19) Video provided by AP
Powered by NewsLook.com
Double-Amputee Becomes First To Move Two Prosthetic Arms With His Mind

Double-Amputee Becomes First To Move Two Prosthetic Arms With His Mind

Buzz60 (Dec. 19, 2014) A double-amputee makes history by becoming the first person to wear and operate two prosthetic arms using only his mind. Jen Markham has the story. Video provided by Buzz60
Powered by NewsLook.com
Navy Unveils Robot Fish

Navy Unveils Robot Fish

Reuters - Light News Video Online (Dec. 18, 2014) The U.S. Navy unveils an underwater device that mimics the movement of a fish. Tara Cleary reports. Video provided by Reuters
Powered by NewsLook.com

Search ScienceDaily

Number of stories in archives: 140,361

Find with keyword(s):
Enter a keyword or phrase to search ScienceDaily for related topics and research stories.

Save/Print:
Share:

Breaking News:

Strange & Offbeat Stories


Space & Time

Matter & Energy

Computers & Math

In Other News

... from NewsDaily.com

Science News

Health News

Environment News

Technology News



Save/Print:
Share:

Free Subscriptions


Get the latest science news with ScienceDaily's free email newsletters, updated daily and weekly. Or view hourly updated newsfeeds in your RSS reader:

Get Social & Mobile


Keep up to date with the latest news from ScienceDaily via social networks and mobile apps:

Have Feedback?


Tell us what you think of ScienceDaily -- we welcome both positive and negative comments. Have any problems using the site? Questions?
Mobile: iPhone Android Web
Follow: Facebook Twitter Google+
Subscribe: RSS Feeds Email Newsletters
Latest Headlines Health & Medicine Mind & Brain Space & Time Matter & Energy Computers & Math Plants & Animals Earth & Climate Fossils & Ruins