Ultra Wide Band (UWB) Radio technology UWB-RT

RF transmission based on Microwave UWB

1

ByVinodQuilonB.Tech Electronics & CommunicationSree Chitra Thirunal College of EngineeringPappanamcode, ThiruvananthapuramKerala, India.25/07/2010

vinodquilon@gmail.com

TABLE OF CONTENTS

ü UWB with narrowband

ü UWB simple transceiver

ü Filter technologies

ü UWB antenna

ü UWB modulation schemes

ü Wireless networking with UWB

ü Spectral encoding multiple access

ü DS-UWB, MB-OFDM transceiver

ü UWB radars

ü UWB in Biotelemetry

ü UWB-MIMO

ü Wireless USB

ü UWB network extension

ü UWB transceiver examples

ü Related technologies

ü Challenges to UWB

ü References2

Wireless Services

• (long range) WMAN– Services like AM,FM,TV,Cellular- WCDMA,CDMA2000

• (short range) – Bluetooth lEEE 802.15.1,IR -infrared, WLAN Wi-Fi IEEE 802.11b, ZigBee, UWB (4 to

20 m range,110 Mbps - 1.6Gbps)

3

HOW DOES UWB FIT IN THE WIRELESS MIX?

4

UWB Vs. Narrow-Band

Shot Noises.

Spread spectrum.

5

Fractional (relative) Bandwidth%BW

UWB is a device with the fractional bandwidth (f.b) greater than or equal to 0.25

6

Definitions NB WB UWB

% BW <1% of centre frequency

1-25% >25%

General FM/AM radio, Telephone

TV WPAN

7

Coexistence of UWB with narrowband systems.

1.6 1.9 2.4

Bluetooth,802.11bCordless PhonesMicrowave Ovens s-bandHome RF

GP

S

PC

S

5

802.11a WLANHyperLAN (20 MHz)

-41 dBm/Mhz“Part 15 Limit” Noise floor

UWB Spectrum

Frequency (Ghz)

EmittedSignalPower

EIRP Emission Level (dBm)

10.63.1

Narrowband(30 KHz)

Wideband CDMA(5 MHz)

MW band

ism bandSpread-Spectrum 802.11b(80 MHz)

PCS- Personal Communication Services (Cellular Phones, Cordless Phones)

ISM- Industry Scientific Medical

U-NII- Unlicensed National Information Infrastructure

U-N

II8

FCC MASK

9

So why is UWB so Interesting?

• 7.5 Ghz of “free spectrum” .(Avoids expensive licensing fees.)

• no interference with the existing wireless systems. (immunity to

detection and intercept) Low transmit power.(share frequency

spectrum) LPD-Low Probability of Detection. Secure.

• Very high data rates possible according to Shannon theorem (Large

channel capacity)

• inherent robustness to multi-path fading (very short duration of UWB

pulses)

• flexibility of operation 10

• Resistance to Jamming (no jammer can jam every frequency in the UWB

spectrum at once). That is high processing gain for UWB signals.

• Ability to work with low SNR(Offers high performance in noisy

environments)

• excellent range resolution capabilities

• low cost of implementation

• Superior penetration properties(The low frequencies included in the broad

range of the UWB frequency spectrum have long wavelengths)

• low-power consumption.(simple transceiver architecture) Smaller form factor

CMOS chipset implementation. Small antennas.11

Narrowband transmitter

UWB transmitter

Typical block diagram of a low power-consuming ultrawideband transmitter

Impulse(chaotic/a periodic ) Modulation for Carrier-less /free transmission.

Pulsed/duty-cycled Modulation.

BPF

Fractal signals 12

Base Band

Narrowband receiver

UWB receiver

Typical block diagram of a low power-consuming ultrawdeband receiver

13

Coherent & Noncoherent architecture

14

For coherent architecture, the template signal is generated according to

transmitted pulse shape. Recover both polarity(amplitude) and position(phase) of

channel /UWB pulse. For non-coherent the template signal can be generated

through an accurate delay line. The energy(envelope) detection is performed by a

mixer used as a square-law device. Recover only the position information by

collecting the energy of the UWB pulses. Avoiding the use of use of a bank of

correlators and pulse matched filter. Timing or frame acquisition in the coherent

receiver is very accurate (accurate ranging).

UWB chipset

15

The layout of the UWB transceiver.

Two technology choices are RFCMOS or SiGe HBT BiCMOS.

Filter Technologies

UWB bandpass filter is a key component of UWB system. It must have an ultra

wide passband, but also needs high selectivity to reject signals from existing

systems such as 1.6 GHz global positioning systems (GPS) and 2.4 GHz Blu-

etooth systems. In addition, in some cases, the UWB bandpass filter needs to

introduce steeply notched frequency bands in order to reduce interference from

existing NB radio systems located within the UWB pass-band.

These requirements increase the challenges for the UWB filter designer.

However, since conventional filter theory is based on the narrowband assumption

and cannot be used to design UWB bandpass filters , novel techniques and

technologies need to be developed for UWB bandpass filter design.16

Ultra wide passband with high selectivity

17

Ultra wide pass band with steeply notched frequency bands

interference suppression

18

UWB filter using electronic-band-gap-loaded optimum-short-circuited stubs

Filter Topology and Fabrication Technology- Single layer PCB

Notched-Band and Rejection Level - NO

microstrip filter- microstrip filters ony become practical above 300MHz. It is a size issue. the

inductance and capacitance of the the microstrip line PCB traces to form the filter, rather then discrete

inductors and capacitors.

19

Filter with Notched-Band and Rejection

20

LNA architecture

21

wideband input impedance matching

The main challenge in UWB designs is to extend matching to the wide frequency range of 3.1-10.6 GHz. The LNA has to exhibit good input impedance.

Resistive terminationcommon gate amplifier

resistive shunt-feedback amplifier 22

UWB Antenna Configurations

Antennas are particularly challenging aspect of UWB. If an impulse is fed to

an antenna, it tends to ring, severely distorting the pulse and spreading

it out in time. Poor matching and large reflections.

Conventional wideband antennas such as the log-periodic and the spiral

are wideband in amplitude, but not in phase; they distort the UWB signal.

The best antennas for UWB are arrays of TEM horns. The higher the frequency

the antennas can be equally small.

23

Constituent

Electrical •wide impedance bandwidth•constant gain at directions of interest•constant desired polarization •high radiation efficiency

Mechanical •small size / low profile/embeddable /easy-integrated for portable devices •compact but robust especially for fixed devices •low cost

24

THE COMPARISON OF DESIGN CONSIDERATIONS FOR UWB ANTENNAS

Typical designs which have been used in various UWB systems

Printed Bow-Tie Antenna

25

NB Interference suppression

A tunable center frequency RF “roofing filter” applied to the UWB NB

interference mitigation problem. This filter will introduce significant group

delay distortion in the passband, and so spectral shaping of the transmitted

waveform out of the interference band will also be required to minimize the

resulting degradation in system performance.

In the second case, an accurate estimation of the frequency, phase, and

amplitude of the jammer is required to significantly reduce the interference

level.26

UWB shows significant throughput potential at short range

27

Although UWB technology is old, its application for

communication is relatively new, thanks to FCC.

Draft standard

28

Impulse waveforms in nature

• Dolphins: 1-100KHz, f.b. 200%

• Bats: 10-150KHz, f.b. 175%

• Swiftlets: 1-5.5KHz, f.b. 140%

29

UWB Modulation Schemes

• 1. PPM (Pulse Position Modulation)

• 2. OOK (On Off Keying)

• 3. BPSK (Binary Phase Shift Keying)

30

UWB modulates an impulse-like waveform (WAVELET) with Data.A typical baseband UWB pulse, also called monopulse, such as the Gaussianfirst derivative pulse can be used.

31

The development of laser-actuated semiconductor fast-acting switches that can produce impulses or short duration waveforms of one or several cycles has been of interest for UWB.

The traveling wave tube (TWT) can be used. It can be excited with a narrow impulse, but its energy is limited by the peak power of the TWT.

WAVELET Generation

PULSE GENERATION

Drift Step Recovery Diode –DSRDDrift Step Recovery Transistor -DSRT

32

Pulse position modulation

33

ON OFF Keying

34

Binary Phase Shift Keying

35

Simulation Results with different Modulations and Gaussian first derivative Pulse for UWB System

36

WIRELESS NETWORKING WITH UWB

• IEEE 802.15.3a HDR WPAN

• IEEE 802.15.4a LDR WSN

• IEEE 802.15.6 LDR WBAN

37

NetworkTopologies

MESH STAR TREE

RFD- reduced-function deviceFFD- full-function device

A piconet is an ad hoc data communications system. As long as the piconets are needed at anytime, the piconets are formed without pre-planning.

38

HDR WPAN

Intercommunications system (ICS)

UWB

39

AWICS

Audio at High rate.

AWICS UWB mobile transceiver with headset

40

LDR WSN

41

Sensors

UWB AP (Access Point)

To identify whether a particular slot in parking area has been occupied.

Sensors produce LDR pulses to indicate slot occupancy. Pulses are guided to Master AP at security cabin,

through Slave APs. Master AP will display exact vacant slot, thus security person can guide the incoming

vehicles to the correct direction.

Wearable WBAN

42

PBS

Fixed AP@ Patient’s Room

Medical Service Centrefor measurement of physiological parameters of a person

UWB

43

• DS Impulse Radio (DS-IR-UWB)

• FH Multiband OFDM (FH-MB-OFDM)

UWB Spectral Encoding multiple access schemes

44

Spectral Encoding helps to spread spectrum.Multiple access schemes implemented to cover large number of nodes in wireless network scenario.

IR-UWB3.1-to 5-GHz range band plan

45

IR-UWB6-to 10.6-GHz range band plan

46

MB-OFDM

4.8

528 MHz Bandwidth for each band

13Band plan

47

IR-UWB MC-OFDM

Modulation Scheme BPSK QPSK

Spreading DS FH

Data Rate LDR HDR

Support UWB Forum WiMedia Alliance

Market Handheld consumer market

PC market

Power Consumption Steady Depends on data rate

Transceiver Architecture Rake Complex

Robustness to Fading YES NO

Sampling Rate Very High > 2 Gbps Reasonable

Channel estimation accuracy

Mandatory Mandatory

Synchronization Time Frequency, Phase, Time

LNA linearity Lower Higher

Primary domain Analog Digital

Other names Impulse Radio, Pulse based

Multi Band- MBMulti Carrier- MC 48

Integration of MultiBand and cognitive radio (CR)

49

Cognitive Radio(CR) is an emerging approach for a more flexible usage of

the precious radio spectrum resources. By investigations on the radio

spectrum usage, it has been observed that some frequency bands are

largely unoccupied most of the time, some other frequency bands are only

partially occupied, and the remaining frequency bands are heavily used.

A CR terminal can sense its environment and location and then adapt

some of its features allowing to dynamically reuse valuable spectrum. This

could lead to a multidimensional reuse (dynamical usage) of spectrum in

space, frequency and time, exceeding the severe limitations in the

spectrum and bandwidth allocations. 50

UWB Trans-ceiver Architecture

51

DS-UWB System Architecture

VGA

PN sequence

ADC at chip rate

52

LNA Gain- 15dB

Bandwidth- up to 7 GHz

NF- 3 dB

Mixer I & Q Bandwidth- up to 7 GHz

PLL Freq Synthesizer Single fixed freq.

Power Amplifier (PA) Power levels -41.3

dDBm/MHz

53

The RAKE receiver, a preferred structure for collecting multi-path energy is a good choice to build IR UWB system.

Rake receiver consists of multiple correlators (fingers) where each of the fingers candetect/extract the signal from one of the multipath components (MPC) provided by the channel. The outputs of the fingers are appropriately weighted and combined (using maximal-ratio combining (MRC)) to reap the benefits of multipath diversity.

Rake receivers, which are based on either partial combining (called PRake) or selective combining (called SRake). The first is suboptimum and combines the firstarriving multipath components, while the second combines the strongest multipath components. A standard “ideal” Rake receiver that combines all of the resolvable multipath component is called All-Rake (ARake).

The RAKE with a LMS adaptive equalizer and the RAKE with a LMS adaptive combiner perform better than the traditional N-selective MRC RAKE structure in theISI environment.

A reduced complexity combining technique that does not require the estimates of the fading amplitudes is equal gain combining (EGC), where all the multipath components are weighted equally.

RAKE RECEIVER FOR UWB

54

N-selective RAKE

RAKE with an adaptive equalizer

Adaptive RAKE 55

PRakeSRake

56

TR-UWB autocorrelation RxRThe mixer of the standard FSR-UWB scheme has been replaced by adelay element D.

non-coherent differential receiver

57

As an alternative to TH-IR,TR-IR first transmits a reference pulse of known polarity (or

position), followed by a data pulse whose polarity (position) is determined by the

information bit. At the receiver, we then only have to multiply the received signal with a

delayed version of itself, resulting in an extremely simple receiver structure.

Robust-to-Timing TR (RTTR) considerably improves performance of the original TR in

the presence of timing offsets or residual timing acquisition errors.

TR-IR - 6-8 dB degradation compared to coherent receiverSpectral efficiency divided by 2

UWB Transmitted-reference (TR) and frequency-shifted reference (FSR)

ultra-wideband (UWB) systems employ pairs of reference and data signals,

which are shifted in the time and frequency domains, respectively, to facilitate

low-to-medium data rate communications without the need for complex

channel estimation and template signal generation. On the other hand, the

recently proposed coded-reference (CR) UWB systems provide

orthogonalization of the reference and data signals in the code domain, which

has advantages in terms of performance and/or implementation complexity.

58

Sine carrier

Input Data To channel

From channel

RAKE

DS-CDMA

Signal is multiplied by a spreading sequence in the frequency domain.

As a result, the signal spreads in time.

As an alternative to TH-IR, direct-sequence CDMA , a technique well-known from cellular radio, can be used. A large bandwidth is obtained by employing a very high chip rate. 59

MB-OFDM System Architecture

VGA

60

FH-PLL

dual-loop architecture with single-sideband mixing of a fast hopping

61

Fast frequency hopping changes the carrier frequency several times

during the transmission of one symbol; in other words, the transmission of

each separate symbol is spread over a large bandwidth. Slow frequency

hopping transmits one or several symbols on each frequency.

Frequency hopping has a multiple access capability. Different users are

distinguished by different hopping sequences, so that they transmit on

different frequencies at any given time.

62

LNA Gain- 15dB

Bandwidth- 528 MHz/band

NF- 3 dB

Mixer I & Q Bandwidth- 528 MHz/band

PLL Freq Synthesizer Multiple freq.

Power Amplifier (PA) Power levels -41.3

dDBm/MHz

63

UWB Outdoor peer-to-peer network (OPPN)

64

Downloading of video movie purchase or rental, for example, is a

very data-intensive activity that could be enabled by UWB.

65

UWB RADARS

The wide bandwidth of UWB signals implies a fine time resolution that gives them a

potential for high-resolution positioning applications /Localization and tracking

(LT)/ranging, provided that the multipaths are dealt with.

Sensor, positioning, and identification network (SPIN)

As of Short Pulse Width we can Resolve Multipath Components .

precision asset location system(PALS)

Positioning and RFID

66

Short-range radar (SRR)

UWB radar over NB radar• Higher range resolution and accuracy .Ultra High Range Resolution

(UHRR)

• enhanced target recognition

• immunity to passive “interference”

• immunity to co-located radar transmissions

• signals scattered by separate target elements do not interfere

• operational security because of the extremely large spectral spreading

• ability to detect very slowly moving or stationary targets

• Multiple targets can be resolved67

• With a long pulse NB radar waveform, changes in the target aspect

cause a change only in the amplitude of the echo signal. With UWB

signals, however, the shape of the echo signal will change, which

makes efficient signal processing.

• NB signal processing in radar almost always utilizes the envelope.

With UWB waveforms, either the envelope or the RF signal can be

used.

• In indoor and dense urban environments the GPS signal is typically

unavailable.

68

Components of UWB Radar

• S M A L L S C A L E E N V I R O N M E N T ( P I C O N E T )

• U W B T A G / M O B I L E D E V I C E ( M D ) / S E N S O R – T X

• U W B S L A V E A C C E S S P O I N T ( A P ) / S T A T I O N A R Y U N I T / R F D – T X _ R X

• D I G I T A L P R O C E S S I N G U N I T / M A S T E R A P / F F D

• P C A S S E C O N D A R Y P R O C E S S I N G U N I T

69

TAG

70

ceiling mounted UWB AP

Master AP (Hub)

71

THE MEASURING METHOD OF UWB RADAR

72

The time-digitizer converter (TDC) estimate signal parameters,such as Angle-of-

Arrival(AOA), Time of Arrival (TOA), Time Difference of Arrival (TDOA), RTD (Round

Trip Delay) and/or Received Signal Strength(RSS).

Then,in the second step,the Microprocessor-Controlled unit(MC) directs the work of the

radar on given algorithms, based on the signal parameters obtained from the first step

and provides data output for further digital processing in the computer(secondary

processing). Fast Fourier transform, and digital filtration are software-programmable at

the computer.

Display results to the display of a personal computer is made.

73

Three Principles of Positioning

• TOA (Time of Arrival) & RTD (Round Trip Delay)

• TDOA (Time Difference of Arrival)

• AOA (Angle of arrival)

By estimating.............

74

TOA ranging

known nodes (anchors)

TOA one-way-ranging (TOA-OWR) and TOA two-way ranging (TOA-

TWR). The former requires perfect synchronization between TX and RX,

while the latter does not require synchronization between TX and RX.

75

UWB radar Detection of people in an open area

• O P E N A R E A P I C O N E T

• P E O P L E A S U W B T A G / S E N S O R

• A P - R X

• D I G I T A L P R O C E S S I N G U N I T / M A S T E R A P W I T H P C

76

Detection of two persons moving at a distance of 50 meters

output data at pc display

77

UWB radar monitoring of the level of a liquid

This radar provides measurements

of a liquid's level in tankage which

can have a depth from I to 20

meters.

Accuracy of measurements is 5mm.

• T A N K P I C O N E T

• L I Q U I D A S U W B T A G / S E N S O R

• A P - R X

• D I G I T A L P R O C E S S I N G U N I T / M A S T E R A P W I T H P C

78

In an automotive environment, the localization of a wireless key, inside or outside a car and its distance from the car, could be estimated by UWB radar technique.

detection of on-board items inside vehicles. Precision Asset Location (PAL)System

79

Indoor Mapping System

80

Short-pulse RF emissions from the tags are subsequently received by

receivers and processed by the central hub CPU. A typical tag emission

consists of a short burst, which includes synchronization preamble, tag

identification (ID), optional data field (e.g., tag battery indicator), and FEC bits.

Time differences of arrival (TDOA) of the tag burst at the various receiver sites

are measured and sent back to the central processing hub for processing.

Calibration is performed at system startup by monitoring data from a reference

tag, which has been placed at a known location.

81

UWB Radars in Medicine

UWB radar monitor

82

Discrete pulses emitted from the UWB transmitter travel to the human body and

incidence it. The pulses comprising the information reflected from the human

body travel back to the UWB receiver and then the result is recorded. Signal

processing is performed through obtaining the pulses response with the shape

and electrical properties of pulse.

83

UWB radar emissions are safe and the UWB electromagnetic signal is not influenced by clothes or blankets, and the useful range is in the order of a fewmeters.

UWB Radar emits (W tc) a short packet of electromagnetic waves whose echoes (W echo) are sampled using “conventional” UWB receiver.

84

UWB radar-based exploration of arteries

85

OPTICAL UWB RADAR

Instead of emitting a short electromagnetic pulse, a short train-wave of light

(electromagnetic energy as well) is emitted (IR laser diode is used as the

antenna) and the echoes detected by a very fast PIN photodiode (UWB

receiver equipped with a PIN photodiode).

Resulting biomedical applications are quite interesting.

86

through-wall detection UWB radar

20cm

GPR- Ground Penetrating Radar87

Radar cross section (RCS)

Here strongest clutter signal occurs by reflection from a wall and the weakest

expected reflection from a target at the maximal range.

As key functional requirements to the radar we select the separation of a

breathing target from a stationary clutter.

R11m

R3

1GHz

88

GPRGPR was deployed as a backup sensor for a large mining vehicle

89

GPR system block diagram

nicknamed SPIDER

90

vehicular collision avoidance

In this application, an approaching car is detected by using SRR as well

as delivery of warning messages by wireless communication from the

approaching car.

Unmanned Vehicles

91

92

Smart highways- UWB devices placed inside the vehicles enable

them to communicate and, thus, provide real time local intelligence in

order to avoid accidents.

The 2006 Mercedes S-Class uses 24 GHz short range UWB radar as

part of its driver assistant systems. Elapsed time of pulsed signals is

used to detect objects within 0.2 to 30 m. It can detect and track up

to 10 objects with a range accuracy of 7.5 cm.

guarding of objects

The output signals of the guarding sensors

QUick response Perimeter Intrusion Detection –QUPIDused to protect a perimeter from unauthorized intruders.

93

UWB in Biotelemetry

94

LDR UWB ECG Monitoring System

non-coherent energy detector.

patient in ICU

PC @ Doctor’s cabin

95

ECG signals recovered

96

UWB Endoscopereal-time diagnosis with high resolution images.

97

A wireless endoscope system is comprised of a capsule endoscope for image capturing, an

external unit for data recoding, analysis and diagnosis of syndrome in the gastrointestinal

tract.

The capsule endoscope is compose of a miniaturized camera, light-emitting diodes, CMOS

imager, system controller, radio transceiver and battery. And implemented in 0.18µm digital

CMOS.

High data transmission afforded by UWB. 98

UWB-MIMO

99

Virtual-MIMO system for cellular network

100

MIMO (multiple-input multiple Output) techniques provide better spatial

diversity and higher system capacity. With the development of mobile

communication, MIMO techniques will be widely applied into B3G or 4G

mobile communications in the future.

But, most of mobile terminals（MTs）still utilize single antenna/antenna

arrays, so the advantages of MIMO systems can’t be fully exhibited.

To exhibit MIMO, MT with multiple-antenna needed.For that, UWB-based

Virtual-MIMO system for cellular network is proposed. 101

Each AP has a total 9 antennas/antenna arrays and servers the same area of 9 traditional

cells. There are 3 Group Cells connected with AP1, which are

GT1 consisting of MT1 and MT2 antenna arrays connect with each other by UWB

GT2 consisting of MT3 and MT4 one or multiple antennas connect with each other by UWB

GT3 consisting of MT5 and MT6 hybrid antennas composed by antennas/antenna arrays

connect with each other by UWB

One MT can directly communicate with some other MTs nearby without AP’s relaying. Each

MT in GT is able to not only directly communicate with AP, but also connect with AP by

sharing the antennas of other MTs in the same GT.

102

Ultra-wide-band (UWB) technology combined with multiple transmit and

receive antennas (MIMO) is a viable way to achieve data rates of more than

1 Gb/s for wireless communications. MIMO systems allow for a substantial

increase of spectral efficiency by exploiting the inherent array

gain and spatial multiplexing gain of the systems. It is shown that the spectral

efficiency is increased logarithmically and linearly, respectively, for

single transmit and multiple receive antennas (SIMO) and MIMO systems.

For multiple transmit and single receive antenna (MISO) systems, a

threshold for the data transmission rate exists such that the spatial

multiplexing gain can be obtained if the data rate is lower than this threshold.

Two STC (Space Time Coding) schemes for UWB-MIMO are 1S/2A and

2S/2A. 103

Wireless USBUnder the WiMedia umbrella, industry incorporated UWB as the technology

to achieve high data rates up to 480 Mbps for Wireless USB.

To replace the USB cable by providing secure high speed, short range

communications, like USB but without the cables.

”plug and play”

Wireless Ethernet interface link (WEIL)

Belkin CableFree USB

Certified Wireless USB

Affordable commercial UWB hardware has become readily available in the

form of WUSB dongles as of 2011. 104

UWB SATCOM

The UWB signals can be overlaid on the existing narrowband spectrum.

This is expected to contribute to increasing spectrum efficiency of the

satellite systems.

UWB signals for Ku-band downlink with 500 MHz bandwidth. UWB

signals are radiated from satellites to the earth by which new satellite

applications can be developed.

105

Bluetooth over Ultra Wideband (BToUWB)

BToUWB is modeled by channeling an existing compliant Bluetooth connection’s data over a software implemented UWB Medium Access Control (MAC) and simulated Physical (PHY) layer radio channel.

The simulated UWB link may closely resemble a real life UWB connection.

Utilizing the UWB physical layer may provide even more advantages in terms of connection setup speed and device power saving.

106

UWB NETWORK EXTENSION

107

The network is extended to cover wider area. IEEE 1394 can operate over both

copper and fiber single cable. IEEE 1394 is an international standard for high

performance serial bus that will enable simple, low-cost, and high-bandwidth

isochronous/asynchronous data interfacing between UWB buses.

HDR-WPAN

108

UROOF(UWB Radio Over Optical Fiber)

Another technique for UWB Network extension.

109

To recover the information that is carried by the optical phase, we have to convert

a phase-modulated signal to an intensity-modulated signal (PM-IM). A dispersive

Device (single-mode fiber (SMF)) is used to change the phase relationship

between the two first-order sidebands from out of phase to partially or fully in

phase. The electrical signal is obtained at the output of a PD, which is ready to

radiate to the space via an UWB antenna.

LD- laser diodePC- polarization controllerPD- photo detector

UWB/O O/UWB

110

Multiplexing (sharing) between different piconets

• FDM– not attractive

• TDM– require coordination and do not scale well to

higher aggregate data rates. The CSMA mechanism is unsuitable

• CDM– good match for UWB

111

UWB TRANSCEIVER EXAMPLES

•DRACO UWB Network Transceiver

•ORIONUWB Network and Ground Wave Non-LOS Transceiver

112

DRACO

multi-band inter/intra team radio (MBITR)

A DRACO transceiver node can be operated as an unattended communications relay, originating sensor (e.g., video, seismic, acoustic, etc.) communications node, reach back satellite packet node, or destination terminal. 113

ORION L-band UWB radio transceivers.

FPGA contains Burst (De)Interleaver,FEC, Bit Stream Processing, etc.

114

RELATED TECHNOLOGIES

115

Standard Bluetooth Wi-Fi UWB

IEEE spec. 802.15.1 802.11a/b/g 802.15.3a

Frequency band 2.4 GHz 2.4 GHz, 5 GHz 3.1-10.6 GHz

Max. signal rate 1 Mb/s 54 Mb/s 110 Mb/s

Nominal range 10 m 100 m 10 m

Number of RF channels

79 14 (2.4 GHz) 1-15

Channelbandwidth

1 MHz 22 MHz 500MHz-7.5 GHz

Modulation type GFSK BPSK,QPSK BPSK,QPSK

Spreading FHSS DSS DSS,FH

Coexistencemechanism

OFDM-Adaptive OFDM-Dynamic OFDM-Adaptive

Basic cell Piconet BSS Piconet

Extension of basic cell

Scatternet ESS P2P

Maximum number of cell nodes

8 2007 8

Nominal Tx power 0-10 dBm 15-20 dBm -41.3 dBm/MHz116

117

UWB AND THE COMPETING TECHNOLOGIES

118

CHALLENGES TO UWB

• suspicious about the NB interference

• extreme antenna bandwidth requirements

• very accurate timing synchronization need for correlator -based

receiver

• Complex RAKE-type receiver to cope with significant amount of

energy in the multipath

• filter matching accuracy

• timely approval from the regulatory bodies

• lack of an universal standard119

UWB testbed

transmitter receiver

120

References

121

122

ØUWB Systems for Wireless Sensor Networks- Zhang, Sahinoglu- IEEE Proceedings

ØWhy UWB? A Review of Ultra wideband Technology- Miller – DARPA

ØSemiconductor Technology Choices for Ultrawide-Band (UWB) Systems- Harame- IEEE

ØUWB Radars in Medicine -Staderini -IEEE AESS Systems Magazine

ØPhotonic Generation of Ultra wideband Signals- Yao-Journal of Lightwave Technology

ØUWB Localization Techniques for Precision Automobile Parking System –Mary-IEEE

ØUWB Communications Systems :An Overview- Tommy- IEEE

ØOverview of Research and Development Activities in NICT UWB Consortium- Kohno

ØComparative Evaluation of Different Modulation Schemes in UWB - Sharda Mungale

ØAn introduction to UWB communication systems- Rakesh- IEEE

ØUWB Filter technologies- Hao-IEEE Microwave magazine

ØRecent System Applications of Short-Pulse Ultra-Wideband (UWB) Technology-Fontana

ØPerformance of Coherent and Non-coherent Receivers of UWB Communication – IEEE

ØPractical Applications of UWB Technology- Immoreev- IEEE A&E Systems Magazine

ØIntroduction to Ultra-Wideband Communications- Nekoogar

ØEssentials of UWB- Wood, Aiello- Cambridge

ØUWB Radio technology- Siwiak- Wiley

Øhttp://www.timedomain.com/

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