wireless sensor system design a joint course of the university of south florida and tennessee...
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Wireless Sensor System Design
A Joint Course of the University of South Florida
and Tennessee Technological University
Spring 2002
Lecture 5 - Systems Engineering / Effective Presentations
Tennessee TechUNIVERSITY
USF EEL 4935/TTU ECE 4720SPECIAL TOPIC: WIRELESS SENSOR SYSTEMS
Tennessee TechUNIVERSITY
Weekly Lecture Topics Course Introduction Analog and Digital Modulation Methods (1/11) Fundamentals of Antennas and Propagation (1/18) Signal Processing Techniques (1/25) Microwave Systems: Communications Hardware, Noise, Linearity (2/1) System Test, Evaluation and Documentation / Effective Presentation
Styles (2/8) Preliminary Design Review (student presentations*) (2/15) Microwave Sensor Technology (2/22) @ TTU Modern Wireless Communication Systems (3/1) TBD (3/8) Critical Design Review (student presentations*) (3/22) Microelectromechanical Systems (MEMS) Sensors (4/5) Wireless Sensor System Research (Paul Flikkema from NAU) from USF (4/12) Review / Course Wrap-up (4/19)
* On-site internal reviews/preparation will precede inter-university presentations.
USF EEL 4935/TTU ECE 4720SPECIAL TOPIC: WIRELESS SENSOR SYSTEMS
Tennessee TechUNIVERSITY
Today’s Tutorial
Systems Engineering What is it? Why is it needed? Answer through example:
Communication Satellites How does this relate to our project?
Design Integration Test Documentation
USF EEL 4935/TTU ECE 4720SPECIAL TOPIC: WIRELESS SENSOR SYSTEMS
Tennessee TechUNIVERSITY
What is a Communication Satellite?
Repeater in the sky
Two main subsystems: Support functions (BUS) Specific functions
(PAYLOAD)
D/C
AM
P
14 GHz 12 GHz
Note: Full system consists of both space and earth segments
USF EEL 4935/TTU ECE 4720SPECIAL TOPIC: WIRELESS SENSOR SYSTEMS
Tennessee TechUNIVERSITY
Block Diagram for a Satellite System
s tru c tu res
p ro p u ls ion
p o w er
th e rm a l
co n tro ls
B U S
p a ss ive
a c tive
a n te nna
P A Y L O A D
S a te llite
USF EEL 4935/TTU ECE 4720SPECIAL TOPIC: WIRELESS SENSOR SYSTEMS
Tennessee TechUNIVERSITY
Block Diagram of Payload Subsystem
f ilte rs
co u p le rs/iso la to rs
sw itch es
w a ve gu ide
P a ssive C o m p o ne n ts
a m p lif ie rslo w -p o w er
d o w n /upco n ve rte rs
a m p lif ie rsh ig h -po w er
A c tive C om p on e n ts
h o rn s/fe e d n e tw o rks
re fle c to rs
s tru c tu res
A n te nn as
P A Y L O A D
USF EEL 4935/TTU ECE 4720SPECIAL TOPIC: WIRELESS SENSOR SYSTEMS
Tennessee TechUNIVERSITY
Types of Engineers Needed
Numerous disciplines with specialized talents EE
Controls, Electronics, Microwave Devices Antenna, Communications
ME Structures, Dynamics, Thermal
ChemE Propulsion, Fuel Cells
USF EEL 4935/TTU ECE 4720SPECIAL TOPIC: WIRELESS SENSOR SYSTEMS
Tennessee TechUNIVERSITY
? ? ?
Who understands the BIG PICTURE?
USF EEL 4935/TTU ECE 4720SPECIAL TOPIC: WIRELESS SENSOR SYSTEMS
Tennessee TechUNIVERSITY
Who understands the BIG PICTURE?
Systems Engineer Broad base / interdisciplinary knowledge Not about knowing all the answers About knowing and asking the right questions Liaison between subsystems and
management/customers
USF EEL 4935/TTU ECE 4720SPECIAL TOPIC: WIRELESS SENSOR SYSTEMS
Tennessee TechUNIVERSITY
Typical Systems Engineering Problem
Efficiency of 100 W TWTAs are 55 % vs. 60% DC load/unit = 181 W vs. 167 W 14.3 W/unit delta 24 units: 344 W extra
Overall bad situation: Solution 1: Live with it Solution 2: Back-off output power
inDCinRF
outRF
PP
P
__
_
USF EEL 4935/TTU ECE 4720SPECIAL TOPIC: WIRELESS SENSOR SYSTEMS
Tennessee TechUNIVERSITY
Solution 1: Live with it
s tru c tu res
p ro p u ls ion
p o w er
th e rm a l
co n tro ls
B U S
p a ss ive
a c tive
a n te nna
P A Y L O A D
S a te llite Excess power: needed from solar
panels/batteries
USF EEL 4935/TTU ECE 4720SPECIAL TOPIC: WIRELESS SENSOR SYSTEMS
Tennessee TechUNIVERSITY
Solution 1: Live with it
s tru c tu res
p ro p u ls ion
p o w er
th e rm a l
co n tro ls
B U S
p a ss ive
a c tive
a n te nna
P A Y L O A D
S a te llite Excess power: needed from solar
panels/batteries dissipated as heat
USF EEL 4935/TTU ECE 4720SPECIAL TOPIC: WIRELESS SENSOR SYSTEMS
Tennessee TechUNIVERSITY
Solution 1: Live with it
s tru c tu res
p ro p u ls ion
p o w er
th e rm a l
co n tro ls
B U S
p a ss ive
a c tive
a n te nna
P A Y L O A D
S a te llite Excess power: needed from solar
panels/batteries dissipated as heat
Excess heat: larger heat sinks
USF EEL 4935/TTU ECE 4720SPECIAL TOPIC: WIRELESS SENSOR SYSTEMS
Tennessee TechUNIVERSITY
Solution 1: Live with it
s tru c tu res
p ro p u ls ion
p o w er
th e rm a l
co n tro ls
B U S
p a ss ive
a c tive
a n te nna
P A Y L O A D
S a te llite Excess power: needed from solar
panels/batteries dissipated as heat
Excess heat: larger heat sinks larger spacing between
units
Other involved groups: reliability, layout,mass properties, propulsion, launch, etc.
USF EEL 4935/TTU ECE 4720SPECIAL TOPIC: WIRELESS SENSOR SYSTEMS
Tennessee TechUNIVERSITY
Solution 2: Reduce RF output
s tru c tu res
p ro p u ls ion
p o w er
th e rm a l
co n tro ls
B U S
p a ss ive
a c tive
a n te nna
P A Y L O A D
S a te llite Idea: Don’t impact BUS Back off output from
100 W to 91.8 W -0.4 dB change Could eat all the design
margin! Customer is paying for
EIRP!
USF EEL 4935/TTU ECE 4720SPECIAL TOPIC: WIRELESS SENSOR SYSTEMS
Tennessee TechUNIVERSITY
Flow top level specifications to subsystems Flow subsystem specs to units Example: EIRP spec of 55 dBW
Repeater 100 W Amplifier: 20.00 dbW Output Losses: -1.50 dB
Antenna Gain: 38.00 dBi Feed Losses/efficiency: -1.00 dB
Margin > 0.50 dB
Systems Design Strategy
Beating specat a cost?
USF EEL 4935/TTU ECE 4720SPECIAL TOPIC: WIRELESS SENSOR SYSTEMS
Tennessee TechUNIVERSITY
Spec Flow Example Continued
Output Losses -1.50 dB Isolator -0.15 Waveguide* -0.15 *Layout dependent
Switch -0.15 Waveguide* -0.20 Output Filter -0.40 Isolator -0.15 Waveguide* -0.10 Coupler -0.15 Total -1.45 dB
Margin .05 dB
Note: subsystemand unit margins
Known measured value: -0.12 dB
USF EEL 4935/TTU ECE 4720SPECIAL TOPIC: WIRELESS SENSOR SYSTEMS
Tennessee TechUNIVERSITY
Design Evaluation
Proposal Preliminary Design Review (PDR)
internal and external review of system design, schedule and test plan
results in action items Critical Design Review (CDR)
same, but more of it! Test spec and test results
USF EEL 4935/TTU ECE 4720SPECIAL TOPIC: WIRELESS SENSOR SYSTEMS
Tennessee TechUNIVERSITY
Testing: Early and Often
1. Unit Level Ambient Test Burn in, Thermal and
Vibration Ambient Test
2. Subsystem Integration & Test Test as sections Test as subsystem
3. System Test Ambient Test Environmental: Thermal
Vac & Vibe Ambient Test
4. In Orbit Payload Test Bus Test
Testing costs $$$ but ensures reliability
USF EEL 4935/TTU ECE 4720SPECIAL TOPIC: WIRELESS SENSOR SYSTEMS
Tennessee TechUNIVERSITY
What goes in a Specification?
Interface and Performance attributes Physical
Mass Dimensions, Layout
Power DC in Efficiency
Thermal RF and DC dissipation
RF I/O levels Efficiency
Other I/O Telemetry Command Control
USF EEL 4935/TTU ECE 4720SPECIAL TOPIC: WIRELESS SENSOR SYSTEMS
Tennessee TechUNIVERSITY
Other Documentation
Specifications: Unit Subsystem System Test
Design review packages System Summary Test Data
USF EEL 4935/TTU ECE 4720SPECIAL TOPIC: WIRELESS SENSOR SYSTEMS
Tennessee TechUNIVERSITY
Systems Engineering on USF/TTU Project
Subsystem Design
System Integration
Design Review
Design for Test
Documentation
USF EEL 4935/TTU ECE 4720SPECIAL TOPIC: WIRELESS SENSOR SYSTEMS
Tennessee TechUNIVERSITY
TTU and USF Wireless Sensor System
Sensor: Temperature, Light Intensity, Humidity & Location
Data for 12APR02
Time Sensor °C Intensity Humidity1532 26 24 70% 50%1533 14 25 65% 55%1544 29 30 0% 60%… … … … …… … … … …… … … … …
Historical Data:By timeBy sensorBy location
Sensor 14: °C
Date/time
Sensor n
http://www.ece.tntech.edu/472s02/dsp/
USF EEL 4935/TTU ECE 4720SPECIAL TOPIC: WIRELESS SENSOR SYSTEMS
Tennessee TechUNIVERSITY
How can we ensure it will all work together?
Design Strategy: Break the system into subsystems Break subsystems into components Peer review of design Design for test
Integration Strategy: Test and document individual components Test and document subsystem performance Test and document system level performance
Flow of Spec
PDR/CDR
USF EEL 4935/TTU ECE 4720SPECIAL TOPIC: WIRELESS SENSOR SYSTEMS
Tennessee TechUNIVERSITY
Example: Design for Test - RF Transmitter
How can component and subsystem performance be determined in the same design? Design board to accommodate both!
X
VCO
BPF
AM
P
USF EEL 4935/TTU ECE 4720SPECIAL TOPIC: WIRELESS SENSOR SYSTEMS
Tennessee TechUNIVERSITY
Board Layout (AM transmitter)
VC
O
BPF
AM
PXVCO_cntrl
Carrier
Baseband
TX_out
AMP_inMIX_out
Note: other I/O’s areneeded (e.g., power)
BNC connector
USF EEL 4935/TTU ECE 4720SPECIAL TOPIC: WIRELESS SENSOR SYSTEMS
Tennessee TechUNIVERSITY
VCO Testing
VC
O
BPF
AM
PXVCO_cntrl
Carrier
Baseband
TX_out
AMP_inMIX_out
USF EEL 4935/TTU ECE 4720SPECIAL TOPIC: WIRELESS SENSOR SYSTEMS
Tennessee TechUNIVERSITY
Mixer Testing
VC
O
BPF
AM
PXVCO_cntrl
Carrier
Baseband
TX_out
AMP_inMIX_out
USF EEL 4935/TTU ECE 4720SPECIAL TOPIC: WIRELESS SENSOR SYSTEMS
Tennessee TechUNIVERSITY
Modulator Testing
VC
O
BPF
AM
PXVCO_cntrl
Carrier
Baseband
TX_out
AMP_inMIX_out
USF EEL 4935/TTU ECE 4720SPECIAL TOPIC: WIRELESS SENSOR SYSTEMS
Tennessee TechUNIVERSITY
Subsystem Testing
VC
O
BPF
AM
PXVCO_cntrl
Carrier
Baseband
TX_out
AMP_inMIX_out
USF EEL 4935/TTU ECE 4720SPECIAL TOPIC: WIRELESS SENSOR SYSTEMS
Tennessee TechUNIVERSITY
Delivered Subsystem
VC
O
BPF
AM
P
X
X X
X
VCO_cntrl
Baseband
TX_out
USF EEL 4935/TTU ECE 4720SPECIAL TOPIC: WIRELESS SENSOR SYSTEMS
Tennessee TechUNIVERSITY
What goes in our specs?
Interface (I/O) attributes DC
Voltages/Currents Connector type
Baseband Voltages Bandwidth Expected signals Connector type
RF Center frequency Bandwidth/Power Connector type
Other Physical dimensions Anything that might
effect the BIG picture
USF EEL 4935/TTU ECE 4720SPECIAL TOPIC: WIRELESS SENSOR SYSTEMS
Tennessee TechUNIVERSITY
Wrap Up
Component level performance can effect all other subsystems
Systems engineers understand complex relationships and know what questions to ask
Specs are used to coordinate the efforts of different engineering groups
Design reviews check and double check methodology Test and document early and often!
USF EEL 4935/TTU ECE 4720SPECIAL TOPIC: WIRELESS SENSOR SYSTEMS
Tennessee TechUNIVERSITY
Bottom Line
Appreciation of the systems engineering approach to developing complex designs.
Reference
G. Gordon and W. Morgan, Principles of Communications Satellites, Wiley, New York, 1993
USF EEL 4935/TTU ECE 4720SPECIAL TOPIC: WIRELESS SENSOR SYSTEMS
Tennessee TechUNIVERSITY
Technical Presentations
Scenario: 20 minute conference presentation 1 of 6 in your session 150 sessions in a week
You want to make your presentation (out of ~900) memorable!
USF EEL 4935/TTU ECE 4720SPECIAL TOPIC: WIRELESS SENSOR SYSTEMS
Tennessee TechUNIVERSITY
Technical Presentations
What is meant by “effective”?
You get your message across. What is the problem? Why is it important? What did you do?
Don’t bore your audience.
Motivation to listen
USF EEL 4935/TTU ECE 4720SPECIAL TOPIC: WIRELESS SENSOR SYSTEMS
Tennessee TechUNIVERSITY
Three Basic Rules
1. Know your audience Be sure everyone understands your motivation Be sure most people get the big picture of what you
are doing Be sure a few people get the details
2. Know your presentation: Practice
3. Leave them wanting more
USF EEL 4935/TTU ECE 4720SPECIAL TOPIC: WIRELESS SENSOR SYSTEMS
Tennessee TechUNIVERSITY
A True StoryC o n s i d e r t h e u n k n o w n n o n - m a g n e t i c m e d i a t o b e a s t a c k o f h o m o g e n e o u s i s o t r o p i c l o s s y
d i e l e c t r i c l a y e r s . A s s u m e t h a t p r o b i n g a n d m e a s u r i n g r e f l e c t i o n r e s p o n s e i s p e r f o r m e d a t t h e t o p o ft h e m e d i a . T h i s m e t h o d o l o g y i s n o t u n c o m m o n ; e . g . , r a d i o e c h o s o u n d i n g o f g l a c i e r s i s p e r f o r m e di n t h i s m a n n e r . U s i n g t h e h o m o g e n e o u s w a v e e q u a t i o n a s a s t a r t i n g p o i n t , [ 2 ] s h o w e d t h ed e v e l o p m e n t o f a d i s c r e t e - t i m e t w o - c o m p o n e n t w a v e f o r m u l a t i o n f o r E M p r o p a g a t i o n t h r o u g h ah o m o g e n e o u s l o s s y d i e l e c t r i c l a y e r ( 1 ) . E q u a t i o n ( 1 ) d e s c r i b e s t h e r e l a t i o n s h i p b e t w e e n d o w n w a r d
a n d u p w a r d t r a v e l i n g w a v e s { 11 , nn UD } a t t h e t o p o f t h e thn 1 l a y e r t o t h e d o w n w a r d a n d
u p w a r d t r a v e l i n g w a v e s { nn UD , } o f t h e thn l a y e r j u s t a b o v e i t .
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a n d )2exp( 11,1, nnnnn ARs . T h e c u m u l a t i v e l o s s i s g i v e n b y ni iiinA 01 cos ; w h e r e i
i s t h e a t t e n u a t i o n c o e f f i c i e n t , i i s t h e l a y e r t h i c k n e s s a n d i i s t h e a n g l e o f p r o p a g a t i o n i n t h e thi
l a y e r . T h e t i m e f o r w a v e t o p r o p a g a t e t h r o u g h t h e thn l a y e r i s g i v e n b y nnnnt cos .
F o r o u r p u r p o s e , t h e s i g n i f i c a n c e o f ( 1 ) i s t h a t i t i s i d e n t i c a l t o t h a t o f t h e a s y m m e t r i c l a t t i c ef i l t e r f r o m D S P t h e o r y . T h i s f o r m u l a t i o n a l l o w s f o r t h e u s e o f f a s t l a y e r s t r i p p i n g a l g o r i t h m s ( i . e . ,L e v i n s o n o r S c h u r ) t o s o l v e t h e i n v e r s e p r o b l e m a n d t o r e c o n s t r u c t t h e t r a n s f e r ( o r P A R C O R i nD S P ) c o e f f i c i e n t s a s a f u n c t i o n o f t i m e ( o r s p a c e ) . G i v e n a s e t o f c o e f f i c i e n t s , t h e f o r w a r ds c a t t e r i n g p r o b l e m c a n b e s o l v e d b y r u n n i n g t h e a l g o r i t h m s b a c k w a r d s a n d s y n t h e s i z i n g a r e s p o n s e .B o t h p r o b l e m s a r e s o l v e d e x a c t l y , i n c l u d i n g a c c o u n t i n g f o r m u l t i p l e r e f l e c t i o n s .
USF EEL 4935/TTU ECE 4720SPECIAL TOPIC: WIRELESS SENSOR SYSTEMS
Tennessee TechUNIVERSITY
Slides
Be comfortable with the format (technology) Don’t have too many slides Don’t read your slides! Don’t put too much on your slides
A clear and well-described picture IS worth a thousand words
Use colors and shapes
USF EEL 4935/TTU ECE 4720SPECIAL TOPIC: WIRELESS SENSOR SYSTEMS
Tennessee TechUNIVERSITY
Traffic Monitoring Sensor - Case Study
900 MHz Signal Relay
Antenna2.45 GHz Hardware20 MHz Hardware
Radar Subsystem Signal Analysis
2.45 GHz
20 MHz
LNA
Coupler
Demodulator
ModulatorAntenna
Signal Conditioning
PhaseDetector
Microwave tower Microwave tower
DAQProcessingWeb Posting
AntennaTransmitterReceiver
USF EEL 4935/TTU ECE 4720SPECIAL TOPIC: WIRELESS SENSOR SYSTEMS
Tennessee TechUNIVERSITY
Traffic Monitoring Sensor - Case Study
900 MHz Signal Relay
Antenna2.45 GHz Hardware20 MHz Hardware
Radar Subsystem Signal Analysis
2.45 GHz
20 MHz
LNA
Coupler
Demodulator
ModulatorAntenna
Signal Conditioning
PhaseDetector
Microwave tower Microwave tower
DAQProcessingWeb Posting
AntennaTransmitterReceiver
USF EEL 4935/TTU ECE 4720SPECIAL TOPIC: WIRELESS SENSOR SYSTEMS
Tennessee TechUNIVERSITY
Things Microsoft never told you.
Don’t let gimmicks bog down your presentation content over flash
Make sure the colors are appropriate to the presentation method
Be sure versions are compatible Pre-load and check your files Have a back up!
USF EEL 4935/TTU ECE 4720SPECIAL TOPIC: WIRELESS SENSOR SYSTEMS
Tennessee TechUNIVERSITY
Another way of looking at things
Personal style – eye contact with audience, speaking with authority, show your own high interest, good posture, etc.
Voice – single tones are only good for RF measurements!
Movement – force the audience to keep their eyes alert, and watch you not just the slides
Time and space – if you don’t spend time on the material why should your audience?
Adjust to audience – are they following you?
USF EEL 4935/TTU ECE 4720SPECIAL TOPIC: WIRELESS SENSOR SYSTEMS
Tennessee TechUNIVERSITY
Preliminary Design Review - Next Friday (15Feb)
Internal reviews by teams TTU on Wednesday (13Feb) USF on TBD.
TTU will have 30 minutes and USF 15 minutes on Friday. Teams will need to work together to produce a single presentation
for each school.
No formal report is to be written, but all the relevant information should be in the presentation slides (provide hard copy). Design details, specifications, I/O, test and integration schedule Each school should also address the open issues that need to be
resolved so that integration with the other sub-systems can take place.
USF EEL 4935/TTU ECE 4720SPECIAL TOPIC: WIRELESS SENSOR SYSTEMS
Tennessee TechUNIVERSITY
February Week 4 (28-1)
First progress report Week 5 (4-8)
Review peer reports Week 6 (11-15)
Preliminary Design Review Week 7 (18-22)
Weller at TTU
Two Month Course Schedule
1. All inputs are due on Friday of the specified week - no exceptions2. Reviews of peer reports must be completed before the lecture on Friday
March Week 8 (25-1)
Second progress report Week 9 (4-8)
Review peer reports Spring Break (11-15) Week 10 (18-22)
Critical Design Review Week 11 (25-29)
No TTU class (F)
USF EEL 4935/TTU ECE 4720SPECIAL TOPIC: WIRELESS SENSOR SYSTEMS
Tennessee TechUNIVERSITY
Anything else?