uwb and applications

UWB & APPLICATIONSThomas George. CS7 ECE

SCMS School of Engineering and Technology

TOPICS COVERED

Introduction to UWB Comparison of UWB with other wireless

technologies Advantages Applications in various fields conclusion

Introduction to UWB

Narrow pulses have a wide frequency response.

FREQUENCY RESPONSE

Introduction to UWB

A pulse is narrow in time and wideband in frequency

Sinusoidal signals are narrow in frequency and "wide" over time

Narrowband Problems • Multipath fading

Destructive interference of CW signals causes signal loss

• Insecure Narrow Band signals are easily detected and jammed • Poor range resolution

Range resolution for tracking applications is a function of RF bandwidth

• Limited data rate Narrow RF bandwidth means narrow data bandwidth

Introduction to UWBLimitations of narrowband communication

Introduction to UWB Uses narrow pulses(pulse width = nS) of very low duty

cycles. Very high band width ( in GHz range) The first ever radio(spark gap radio) was a form of UWB

radio, but found no use UWB technology gained strength when FCC provided 3.1 to

10.6 GHz for unlicensed use in 2002.

So what is ultra wide band technology?

UWB

3.1-10.6 GHz

The history of UWB Technology Before 1900: Wireless Began as UWB

Large RF bandwidths, but did not take advantage of large spreading gain 1900-40s: Wireless goes ‘tuned’

Analog processing: filters, resonators ‘Separation of services by wavelength’ Era of wireless telephony begins: AM / SSB / FM Commercial broadcasting matures, radar and signal processing

1970-90s: Digital techniques applied to UWB Wide band impulse radar Allows for realization of the HUGE available spreading gain

Now: UWB approved by FCC for commercialization

Introduction to UWB

A low energy level, short-range & large bandwidth technology in radio frequency spectrum

Very large bandwidth, >500MHz Very low average power:

Should not exceed -43.1 dBm Fractional bandwidth > 0.25

(fh and fl are highest and lowest frequency)

Definitions and regulations of UWB

Comparison of UWB ,NB and SS

Properties of UWB

Extremely difficult to detect by unintended users Highly Secured

Non-interfering to other communication systems It appears like noise for other systems

Both Line of Sight and non-Line of Sight operation Can pass through walls and doors

High multipath immunity Common architecture for communications, radar & positioning

(software re-definable) Low cost, low power, nearly all-digital and single chip

architecture

Summary of the FCC Rules Significant protection provided for sensitive systems

GPS, Federal aviation systems, etc. Lowest emission limits ever by FCC Allows UWB technology to coexist with existing radio services

without causing interference FCC opened up new spectrum for UWB transmissions

One of the bands is from 3.1GHz to 10.6GHz Maximum power emission limit is - 41.3dBm/MHz

Comparison

Power radiated

Device type Transmit Power (Watts)

Allowed leakage from a MicroWave oven 1.00000 Watt

Typical mobile phone transmit power 0.25000 Watts up to 1 Watt

Class 1 Bluetooth device (100 m range) 0.10000 Watts

Class 2 Bluetooth device (10 m range) 0.00250 Watts

Sunlight reflecting from the head of a pin (on a sunny day)

0.00100 Watts

UWB device 0.00005 Watts

FCC UWB Device Classifications

Report and Order authorizes 5 classes of devices with different limits for each: Imaging Systems

Ground penetrating radars, wall imaging, medical imaging Thru-wall Imaging & Surveillance Systems

Communication and Measurement Systems Indoor Systems Hand-held Systems

Vehicular Radar Systems collision avoidance, improved airbag activation, suspension

systems, etc.

FCC LimitationsClass / Application Frequency Band for Operation

at Part 15 LimitsUser

Limitations

Communications and Measurement Systems

3.1 to 10.6 GHz(different “out-of-band” emission limits for

indoor and hand-held devices)No

Imaging: Ground Penetrating Radar, Wall, Medical Imaging

<960 MHz or 3.1 to 10.6 GHz Yes

Imaging: Through-wall <960 MHz or 1.99 to 10.6 GHz Yes

Imaging: Surveillance 1.99 to 10.6 GHz Yes

Vehicular 22 to 29 GHz No

Modulation techniques DS UWB modulation techniques

Pulse Position Modulation (PPM) Bipolar Signaling (BPSK) Pulse Amplitude Modulation (PAM) On/Off Keying (OOK) Pulse-Shape Modulation

Multi band OFDM suggested for data transmission Use FFT to achieve high data rates.

DS Modulation techniques A number of modulation schemes may be used with UWB

systems. The potential modulation schemes include both orthogonal and antipodal schemes.

Pulse Position Modulation (PPM)

Pulse Amplitude Modulation (PAM)

On-Off Keying (OOK)

Bi-Phase Modulation (BPSK)

Band Plan for MB OFDM Group the 528 MHz bands into 4 distinct groups

Group A: Intended for 1st generation devices (3.1 – 4.9 GHz) Group B: Reserved for future use (4.9 – 6.0 GHz) Group C: Intended for devices with improved SOP performance (6.0 – 8.1 GHz) Group D: Reserved for future use (8.1 – 10.6 GHz)

f3432MHz

3960MHz

4488MHz

5016MHz

5808MHz

6336MHz

6864MHz

7392MHz

7920MHz

8448MHz

8976MHz

9504MHz

10032MHz

Band#1

Band#2

Band#3

Band#4

Band#5

Band#6

Band#7

Band#8

Band#9

Band#10

Band#11

Band#12

Band#13

GROUP A GROUP B GROUP C GROUP D

Advantages of UWBAdvantage Benefit

Coexistence with current narrowband and wideband

radio services

Avoids expensive licensing fees.

Large channel capacity High bandwidth can support real-time high-

definition video streaming.

Ability to work with low SNRs Offers high performance in noisy environments.

Low transmit power Provides high degree of security with low probability

of detection and intercept.

Resistance to jamming Reliable in hostile environments.

High performance in multipath channels Delivers higher signal strengths in adverse

conditions.

Simple transceiver architecture Enables ultra-low power, smaller form factor, and

better mean time between failures, all at a reduced

cost.

More advantages

The low power requirement eliminates the need of a power amplifier in the transmitter

Adding security for data transmission is easy. Simple CMOS transmitters at very low power

available, suitable for battery driven devices

UWB Major Application Areasa) Communications

–Wireless Audio, Data & Video Distribution

–RF Tagging & Identification

b) Radar

–Collision/Obstacle Avoidance

–Precision Altimetry

–Intrusion Detection (“see through wall”)

–Ground Penetrating Radar

c) Precision Geolocation

–Asset Tracking

–Personnel localization

Some of Military & Commercial Applications of UWB

Source:MSSI

Applications of UWB

WPAN: wireless personal area network Small network of devices and host

Bluetooth was previously used Bandwidth of bluetooth is very low ( ≈ 1 MbPS) UWB can replace bluetooth for WPANs

1. WPANs

UWB can enable a wide variety of WPAN applications.

• Replacing IEEE1394 cables between portable multimedia CE devices, such as camcorders, digital cameras, and portable MP3 players, with wireless connectivity

• Enabling high-speed wireless universal serial bus (WUSB) connectivity for PCs and PC peripherals, including printers,scanners, and external storage devices

• Replacing cables in next-generation Bluetooth Technology devices, such as 3G cell phones, as well as IP/UPnP-based connectivity for the next generation of IP-based PC/CE/mobile devices

• Creating ad-hoc high-bit-rate wireless connectivity for CE,PC, and mobile devices

Content Transfer: Mobile Devices

Applications Smartphone/PDA, MP3, DSC Media Player, Storage, display

Requirements Mobile device storage sizes

Flash 5, 32, 512, 2048 … MB HD 4, …, 60+ GB

Range is near device (< 2m) User requires xfer time < 10s

Print from handheld

Images from camera to storage/network

MP3 titles to music player

MPEG4 movie(512 MB) to player

Mount portable HD

Exchange your music & data

Low Power Use Cases

Low Power & High Data Rate Use

Wireless USB

Inadequacy of current wireless solutions: Bluetooth

Bandwidth of 3 Mbps is not enough for most of the applications which needs very high bandwidth. The applications like video, HDTV, monitor etc. are good examples.

Wi-Fi One of the main disadvantage of Wi-Fi is its high expense to set up a network and make it working. It

is not always feasible to install Wi-Fi for home or personal networks.

Another draw back of Wi-Fi is the higher power consumption. Power consumption is one of the important hurdles of wireless designers. As the wireless devices work on their own power, almost always battery power, the high power consumption becomes a big drawback.

Wireless USB

Wireless USB

Wireless USB is used in game controllers, printers, scanners, digital cameras, portable media players, hard disk drives and flash drives. It is also suitable for transferring parallel video streams.

Due to high data rate, HD videos can be transmitted live without wires.

As in USB 2.0 a WUSB hub supports 127 devices It frees the USB devices from cables. To back support the devices, a WUSB hub is also developed

Wireless USB

• Due to absence of physical ports port expansion is easy• Host

USB interface of host computer system – Host ControllerWire Adapters

Belkin Wireless USB hub

In 2006 it was predicted that Bluetooth 3.0 will have data ratesUp to 480 Mbps using UWB

But due to standardization issues, it accepted the 60-GHz technology, which provides a data rate of 24 Mbps.

Bluetooth 3.0

Applications of UWB

Due to high bandwidth and short pulse duration, UWB radars can be used for penetration RADARs.

As it is spread over a wide range jamming is not possible

RADAR application

 Ground and Ice Penetrating RADAR

• A system used to detect objects buried in the ground.

•A special directional antenna to transmit the stimulus signal into the ground and receive the reflected waves.

•Depth of penetration is typically between 0.5 and 10 m, very short pulses are needed to resolve typical buried targets.

Wall Imaging Radar System•To detect the location of objects contained within a "wall," such as a concrete structure, the side of a bridge, or the wall of a mine.

•Operation is restricted by FCC to law enforcement, fire and rescue organizations, to scientific research institutions, to commercial mining companies, and to construction companies.

Through Wall Radar System

•Uses very short pulses to provide detection of objects on the opposite side of a non-metallic wall.

•The stimulus signal is transmitted into the wall. A portion of the signal incident on the wall is transmitted through the wall and into the space on the far side.

•Objects in the field then reflect the signal back to the wall where part of the signal is transmitted through the wall to the receiver.

•Freq of Operation: below 960 MHz or 3.1-10.6 GHz band.

Vehicular Radar SystemsPotential applications include

• collision avoidance,

• proximity aids,

•intelligent cruise control systems,

•improved airbag activation

•suspension systems that better respond to road conditions.

•FCC limits operation of vehicular radar to the 22-29 GHz band using directional antennas on terrestrial transportation vehicles provided the center frequency of the emission and the frequency at which the highest radiated emission occurs are greater than 24.075 GHz.

Medical application

• Penetrating through obstacles

• High precision ranging at the centimeter level

• Low electromagnetic radiation

• Low processing energy consumed

Used for…• Patient monitoring( movement, vital signs, medical store security)• Medical imaging ( cardiac imaging, pneumology, ENT, Obstretrics)

Medical imaging

Other applications• Wireless Sensor networks( military and commercial use)• Automotive industry (collision avoidance, roadside assistance)• Tagging and identification• Non LOS communication• Intrusion detection

Challenges in UWB• Main challenge is in the standardization. Different countries allocated

different spectral regions for unlicensed use.• Design of antenna• Due to power limit set by FCC, the high data rate is available only in

short range ( <10 m)

Conclusion

UWB technology has very high potential in real life applications, due to its high bandwidth and low power.

Very interesting application in wireless content transfer, especially for HD videos.

References

Ultra-wideband communications: fundamentals and applications-F Nekoogar – 2005

K. Siwiak and D. McKeown, Ultra-Wideband Radio Technology, Wiley: UK, 2004.

J. McCorkle, “A Tutorial on Ultrawideband Technology,” Doc. IEEE 802.15-00/082r0, March 2000.

Young Man Kim. Ultra Wide Band (UWB) Technology and Applications. Ohio State University NEST group.