QuickStudy: Ultrawideband
Computerworld -
Listen to the Computerworld TechCast: Ultrawideband.
There's certainly no lack of choices when it comes to wireless communications and networking technologies. With all the currently available forms of wireless access -- cell phones, 3G, Wi-Fi, WiMax, Bluetooth, power lines, and 802.11a, b, g and n -- you wouldn't think there's room for anything more. But technology marches forward, and in the next couple of years, we're going to be seeing a new and different wireless technology. The new kid on the radio block is ultrawideband, also known as UWB or digital pulse wireless. It will help deliver television programs, movies, games and multimegabyte data files throughout our wireless homes and offices. UWB is faster than current wireless LAN technologies and provides a short-range, high-bandwidth pipe that eliminates interference.
Origins of UWB
Gerald F. Ross first demonstrated the feasibility of UWB waveforms for radar and communications applications in the late 1960s and early 1970s. Originally developed by the Defense Advanced Research Projects Agency, the technology was called baseband, carrier-free, impulse communications or time-domain signaling, until the U.S. Department of Defense named it ultrawideband in 1989.
In some respects, UWB technology goes back to the dawn of radio and Guglielmo Marconi's early spark-gap transmissions. UWB is also a successor to spread-spectrum radio (also called frequency-hopping), a World War II technology that splits a broadcast across many different radio frequencies, using one at a time to avoid jamming. (Curiously enough, spread spectrum was invented -- and patented -- in 1942 by actress Hedy Lamar and composer George Antheil.) In contrast, UWB uses every frequency available to it, all at the same time.
UWB isn't a direct substitute for any other form of wireless communications, but it does some things that no other technology can match. A UWB transmitter sends billions of short-duration pulses across a wide spectrum of radio frequencies. These RF bursts come so fast -- lasting only from a few trillionths of a second to a few nanoseconds -- that each actually uses only a few cycles of an RF carrier wave.
This short duration gives UWB waveforms some unique properties. They are relatively immune to multipath cancellation effects, such as when a strong reflected wave arrives out of phase with the direct path signal, reducing the signal strength in the receiver. UWB pulses are so short that the direct signal has come and gone before the reflected path arrives, so no cancellation takes place. Because UWB pulses are so short, they can use very wide frequency spectra; this allows signals to use very low power, which minimizes interference with and from other radio frequencies, reduces health hazards and often falls below the normal noise floor, thus making it harder to detect.



- Excel 2010 Cheat Sheet
- Register for this Computerworld Insider Cheat Sheet and gain access to hundreds of premium content articles, guides, product reviews and more.
- Digital Transformation: Creating New Business Models Where Digital Meets Physical
- Individuals and businesses alike are embracing the digital revolution. Social networks and digital devices are being used to engage government, businesses and civil...
- Empowering Your Mobile Worker
- Today's most productive employees are mobile, and your company's IT strategy must be ready to support them with 24/7 access to the business...
- An Interactive Guide: Bring Your Own Device
- BYOD presents significant security and management challenges to IT departments who want to take advantage of the trend, but still protect corporate assets....
- Calculating ROI for Mobile Client Acceleration
- As mobile devices continue to expand in business use, ensuring these devices have optimal performance is becoming an IT imperative. This EMA paper...
- Tablet Computing Without Compromise
- This paper provides an overview of how and why that migration-from any old tablet to Windows tablets-came to be. All Mobile and Wireless White Papers
- Live Webcast
North Pole to South Seas: Overcoming the Pitfalls of remote Performance - In today's always-on world, connectivity is a business requirement. You need the tools that allow you to operate as if you were on...
- Supporting Mobile Productivity With A Limited IT Budget
- Join us and hear from Kaseya mobile IT management experts as we discuss core strategies for supporting the mobile revolution on a shoestring...
- North Pole to South Seas: Overcoming the Pitfalls of remote Performance
- In today's always-on world, connectivity is a business requirement. You need the tools that allow you to operate as if you were on...
- Unified Communications 101
- What's the best way to implement a unified communications solution for your organization?
- QNX® and BlackBerry® PlayBook™ Tablet.
- RIM's multi-processor, multi-tasking BlackBerry PlayBook runs a new Tablet OS powered by QNX, a bullet-proof microkernel operating system. This track will take a...
- A Close Look at Tablets
- Learn More All Mobile and Wireless Webcasts