RF transmission based on Microwave UWB 1 By VinodQuilon B.Tech Electronics & Communication Sree Chitra Thirunal College of Engineering Pappanamcode, Thiruvananthapuram Kerala, India. 25/07/2010 [email protected]
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RF transmission based on Microwave UWB
1
ByVinodQuilonB.Tech Electronics & CommunicationSree Chitra Thirunal College of EngineeringPappanamcode, ThiruvananthapuramKerala, India.25/07/2010
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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