UWB(Ultra wide band)UWB(Ultra wide band)

Presented by :

K.RAJENDHAR

10011D4517

INTRODUCTION UWB is a wireless technology that transmits binary data—the

0s and 1s that are the digital building blocks of modern information systems. It uses low-energy and extremely short duration (in the order of pico seconds) impulses or bursts of RF (radio frequency) energy over a wide spectrum of frequencies, to transmit data over short to medium distances, say about 15—100 m. It doesn’t use carrier wave to transmit data.

Ultra Wide Bandwidth (UWB) can handle more bandwidth intensive applications – such as streaming video – than either 802.11 or Bluetooth because it can transmit data 10 times faster than the typical DSL line, cable modem or 802.11b. It has a data rate of roughly 100 Mbps, with speeds up to 500 Mbps. Compare that with the maximum speeds of 11 Mbps for 802.11b, called Wi-Fi, which is the technology currently used in most wireless LANs. Bluetooth has a data rate of about 1 Mbps.

So why is UWB so Interesting?

• 7.5 Ghz of “free spectrum” in the U.S.– FCC recently legalized UWB for commercial use– Spectrum allocation overlays existing users, but its allowed

power level is very low to minimize interference• Very high data rates possible

– 500 Mbps can be achieved at distances of 10 feet under current regulations

• “Moore’s Law Radio”– Data rate scales with the shorter pulse widths made possible

with ever faster CMOS circuits• Simple CMOS transmitters at very low power

– Suitable for battery-operated devices– Low power is CMOS friendly

INFORMATION MODULATION

Pulse Position Modulation (PPM)

Pulse Amplitude Modulation (PAM)

On-Off Keying (OOK)

Bi-Phase Modulation (BPSK)

Pulse length ~ 200ps; Energy concentrated in 2-6GHz band;

Voltage swing ~100mV; Power ~ 10uW

Why is UWB so Effective

The Hartley-Shannon Law :

C =B log 2(1+S/N)

Where:

C = Max Channel Capacity (bits/sec) B = Channel Bandwidth (Hz)S = Signal Power (watts)N = Noise Power (watts)C grows linearly with B, but only logarithmically with S/N. Since B is very high C also becomes very high.

Ultra Wideband Characteristics

• Extremely low transmission energy ( less than 1mW)• Very high bandwidth within short range (200Mbps within 10m)• Multipath immunity• Commonality of signal generation and processing architectures• Radar – Inherent high precision – sub-centimeter ranging – Wideband excitation for detection of complex, low RCS targets• Geolocation/Positioning – Sub-centimeter resolution using pulse leading edge detection – passes through building blocks, walls, etc. • Low Cost – Nearly “all-digital” architecture – ideal for microminiaturization into a chipset• Frequency diversity with minimal hardware modifications

UWB Application 1 : WPAN

MobileMobileClusteCluste

rr

handheld handheld PCsPCs

tabletstablets

MP3MP3

PDAsPDAs

mobile mobile phonephone

3G3Ghandsetshandsets

camera camera phonesphones

laptopslaptops

printerprinterss

speakersspeakers

PCPCClusteCluste

rr

storagestoragedevicesdevices

ScannersScanners

scannersscanners

DVDDVDplayersplayers

• Desktop and Laptop PCs

– High res. printers, scanners, storage devices, etc

– Connectivity to mobile and CE devices

• Mobile Devices

– Multimedia files, MP3, games, video

– Personal connectivity

• CE Devices

– Cameras, DVD, PVR, HDTV

– Personal connectivity

One PHY for Personal Computing, Consumer Electronic and Mobile, Wireless Personal Area Connectivity

One PHY for Personal Computing, Consumer Electronic and Mobile, Wireless Personal Area Connectivity

cameracamerass

CECEClusteCluste

rr

HDTVHDTV

STBsSTBs

VCRsVCRs

PVRsPVRs

camcorderscamcordersconsole console gamesgames

audioaudiosystemssystems

UWB Application 2

• Positioning, Geolocation, Localization High Multipath Environments Obscured Environments

• Communications High Multipath Environments Short Range High Data Rate Low Probability of Intercept/ Interference

• Radar/Sensor : MIR (motion detector, range-finder, etc.) Military and Commercial: Asset Protection Anti-Terrorist/Law Enforcement Rescue Applications

ADVANTAGES

Doesn’t suffer from multi-path interference.

High data carrying capacity.

It need only low power.

Low energy density.

Minimum complexity.

Low cost.

Highly secure.

DISADVANTAGES

UWB is not a long –range system.

Frequency sharing with existing users is a problem.

The technology too is at an early stage of development and standardization is incomplete.

CONCLUSION

Ultra wide band has the potential to become a viable and competitive technology for short-range high-rate WPANs as well as lower-rate and low-power consuming low-cost devices and networks with the capability to support a truly a pervasive user-centric and thus personal wireless world.

UWB is undoubtedly a niche technology which holds promise in a wide area. But, its success depends on scoring against a handful of rival technologies in which companies have invested billions. Those who’ve invested their money will not hasten to consider an upstart rival, even if it offers better services.

Now, visualize what happens when you heave a large rock into a small pond. It splashes out the water in one go (as seen with our [censored] eyes). If captured as a still photo, we’ll see the millions of water droplets that splash out in a fraction of a second and make the splash we see. If ripples are like normal transmission of data between wireless devices (as in blue-tooth or Wi-Fi), UWB promises to be the ‘huge rock’ in data transmission.

REFERENCES

http://www.techonline.comhttp://www.pcquest.comhttp://www.uwbplanet.com

K.RAJENDHAR

Presented by:

THAN”Q “THAN”Q “