Ultra-Wideband Research
and Implementation
By Jarrod Cook and Nathan Gove
Advisors:
Dr. Brian Huggins
Dr. In Soo Ahn
Dr. Prasad Shastry
Presentation Outline


Introduction
Overview




Modulation




Brief History of UWB
Consumer Electronics
Demand
Spectrum Overview
QPSK
OFDM
Progress
Baseband Transmitter

Radio Frequency (RF)










Transmitter
Receiver
Progress
Baseband Receiver
Requirements
Equipment List
Schedule
Patents
Future Plans
Questions
Introduction to UWB
Ultra-wideband technology is a wireless
transmission technique approved for
unlicensed use in 2002 under the FCC
Part 15
 Ideal for portable multimedia devices
because of its inherent low power
consumption and high bit rates

Why Research UWB?

UWB is likely to revolutionize the
consumer electronic market in the near
future.
Wireless USB devices
 Wireless communication for High-Definition
devices


UWB has the power to eliminate the
majority of wires to and from multimedia
devices
Overview

Brief History
IEEE 802.15.3a
 ECMA 368 and 369


Consumer Electronics Demand
High data-rate wireless transmissions
 Low power consumption for portable devices


UWB allows data rate equivalent to USB
2.0 (480 Mb/s)
Project Summary


The goal of this project is to complete a scaleddown version of a UWB transceiver.
Specifically, we will focus on the following:






Understanding the theory
Simulink modeling
DSP implementation
RF Modeling/simulation
RF transceiver hardware fabrication
Testing
Wireless Transmission Methods

Narrowband

Advantages






Wideband

Range
Conservation of
spectrum
Cost
Disadvantages


Power consumption
Limited bandwidth
Limited data rates
Advantages




High data rates
Low power
consumption
Spectrum coexistence
Disadvantages


Range
Power output
regulations to prevent
interference
UWB Spectrum Overview

Power spectral density
-41.3 dBm/MHz
 FCC part 15 limit


Frequency Range
3.1 to 10.6 GHz
 Sub-bands

Modulation

QPSK or 4-QAM
Gray Coded Mapping
 Symbols
 Used for data rates from
80 to 200 Mb/s
 I and Q


16-QAM or DCM

Used for data rates from
320 Mb/s to 480 Mb/s
OFDM
Benefits


Resistance to multi-path fading
Spectrum


Full ECMA standardized UWB spectrum
P0
D0
-64
-63
-62
G0
G4
-61
-57
-56
P1
D1
-55
-54

D9
-46
P2
D10
-45
-44
D18
-36
P3
D19
-35
-34
D27
-26
P5
P4
D28
-25
D36
-24
-16
D37
-15
-14
D38
-13
D39
-12
D40
-11
D41
D42
-10
-9
D43
-8
D44
-7
D45
-6
P6
D46
-5
-4
D47
-3
D48
-2
D49
-1
D50
DC
1
D51
2
D52
3
D53
P7
D54
4
5
6
D55
7
D56
D57
8
9
D58
10
D59
11
D60
12
D61
P8
D62
13
14
D63
15
D71
16
24
P9
D72
25
D80
26
34
P10
D81
35
36
D89
44
P11
D90
45
46
D98
54
Scaled-down project spectrum
P5
Byte 1
-16
-15
-14
P6
Byte 2
Byte 3
D38
D39
D40
D41
D42
D43
D44
D45
-13
-12
-11
-10
-9
-8
-7
-6
-5
Byte 4
D46
D47
D48
D49
-4
-3
-2
-1
DC
Byte 5
D50
D51
D52
D53
1
2
3
4
5
Byte 6
D54
D55
D56
D57
D58
D59
D60
D61
6
7
8
9
10
11
12
13
14
15
16
D99
55
56
G5
G9
57
61
62
63
64
OFDM
Frequency Subcarrier
(not delta function)
To Time
Domain
Signal
TD Signal
into Freq.
Domain
To Time
Domain
Signal
TD Signal
into Freq.
Domain
fi
Frequency Subcarrier
(not delta function)
f1 f2
fN
Baseband Transmitter
To facilitate all of the modulation
techniques for UWB, a TI C6000 Series
DSP platform will be used.
 Block Diagram

Current Progress

Simulink Modeling

Simple transmitter, channel, receiver
completed
Simulink Simulations
Transmitted Spectrum & Symbols
Received – SNR = 30 dB
BER = 0.0
Received – SNR = 20 dB
BER = 0.013
Received – SNR = 10 dB
BER = 0.310
Radio Frequency Hardware

Transmitter

Block Diagram
Antenna
I
Q
Direct Quadrature
Modulator
PA
Filter
Oscillator

Direct Quadrature Modulator
 Modulates
the I and Q components
 Pre-fabricated chip will be purchased
Quadrature Modulator

Block Diagram
I component
RF output
Q component
Local Oscillator



A local oscillator will provide the carrier
frequency that is desired.
Mixers shift the I and Q baseband frequencies to
the carrier frequency.
The two components are combined to produced
the RF signal.
Filtering
Antenna
I
Q
Direct Quadrature
Modulator
PA
Filter
Oscillator

Band-pass filters are needed to prevent
any spurious frequencies from the mixing
process to be transmitted.
Amplification

Power Amplifiers
Required to boost signal strength before
transmission.
 This stage will present challenges regarding
maximum output power allowed by the FCC
for UWB transmissions.
 The design will depend on the quadrature
modulator specifications which are TBD.

Antenna


A UWB antenna will
either be designed or
purchased.
Several types to
consider:

Omni-directional


Dipole
Directional



Horn
Yagi
Patch
Antenna
Antenna design will be challenging due to
the wide bandwidth of the UWB spectrum.
 To meet the FCC Effective Isotropic
Radiated Power (EIRP) guideline, antenna
gain must be taken into consideration.

Receiver

Block Diagram
I
Low Pass Filter
LNA
Pre-Select Filter
To A/D Converter
Q
To A/D Converter
Low Pass Filter
Local Oscillator
Receiver Components

Pre-select filter
Band-pass filter to allow only the frequencies
desired into the receiver.
 Low Noise Amplifier (LNA)

 Boosts
the weak incoming signal to increase signal
to noise ratio.
 Increased receiving range.
 For UWB, noise figure must be very low.
Receiver Components

Down Conversion
Local Oscillator
 Mixers


Filters

Removing spurious components from the
mixing process
Current Progress

Initial Quadrature Modulator research
Hittite Microwave Corporation
 This chip only needs a local
oscillator and power for
external connections.
 Problems

 Output
power is too high
Current Progress

The FCC limit on power spectral density
for UWB is -41.3 dBm/MHz.
This corresponds to 7.413 x 10-5 mW/MHz
 For the total bandwidth of a UWB
transmission, the total EIRP is 39 microwatts,
or -14.1 dBm.
 This will present a challenge in the transceiver
design.

Baseband Receiver
Using an identical DSP board, the analog
RF signal will be sampled, and then
processed in the reverse order of the
baseband transmitter.
 Its function is to restore the original input
data.

Functional Requirements

Baseband Transmitter

The baseband signal bandwidth shall be
determined at a later time, but shall be less
than 528 MHz.
Functional Requirements

RF Transmitter





The maximum power spectral density of the
transmission shall not exceed -41.3 dBm/MHz.
The EIRP shall not exceed -14.1 dBm. Thus, the
maximum output power shall be less than 39
microwatts if using an isotropic radiator.
The transmitter shall have a local oscillator at
precisely at 3.432 GHz.
The transmitted bandwidth shall lie in the region of
3.168 and 3.696 GHz.
The transmitter shall not interfere with any other
wireless devices.
Functional Requirements
The receiver shall be immune to other
non-UWB RF signals.
 The receiver shall have an oscillator that is
capable of adjusting to frequency drifts,
with a nominal frequency of precisely
3.432 GHz.

UWB Development Kits
The first several weeks were spent trying
to find a suitable development kit that
would allow testing to be done on the
technology.
 Five companies were found

Two were out of our budget range
 Two were under development
 The last one did not meet our specifications

Equipment List
Schedule
Patents and Standards
Patents
Number
7139454
7099422
7061442
7020224
Description
Ultra-wideband fully synthesized high-resolution receiver and method
Synchronization of ultra-wideband communications using a
transmitted-reference preamble
Ultra-wideband antenna
Ultra-wideband correlating receiver
Patent Applications
Number
Description
20060165155
System and method for ultra-wideband (UWB) communication
transceiver
20060062277
Ultra-wideband signal amplifier
20060045134
Ultra-wideband synchronization systems and methods
Standards
ECMA 368
ECMA 369
High Rate Ultra Wideband PHY and MAC Standard
MAC-PHY Interface for ECMA-368
Future Work

Baseband processor






RF Transmitter






Find a suitable quadrature modulator
Determine and purchase hardware
Model and Design
Fabricate hardware
Antenna research
RF Receiver




Increase complexity
Research UWB channels
Determine maximum feasible sampling rate
Purchase DSP board
Implement synchronous coherent detection for receiver
LNA Design and modeling
Determine and purchase hardware
Fabricate hardware
Testing
Questions
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