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Vehicle Safety Communications Project VSC Progress Briefing #2 – Task 4 Field Testing – Overview of Hardware and Software Test Track Results. Outline. Overview of Hardware and Software Test Equipment and Interface Format of Data/Findings Test Track Testing Test Track Facilities - PowerPoint PPT Presentation
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11November 4th, 2003November 4th, 2003 Vehicle Safety Communications ConsortiumVehicle Safety Communications Consortium
Vehicle Safety Communications ProjectVehicle Safety Communications ProjectVSC Progress Briefing #2VSC Progress Briefing #2
– – Task 4 Field Testing –Task 4 Field Testing –
Overview of Hardware and SoftwareOverview of Hardware and Software
Test Track ResultsTest Track Results
22November 4th, 2003November 4th, 2003 Vehicle Safety Communications ConsortiumVehicle Safety Communications Consortium
OutlineOverview of Hardware and Software
Test Equipment and Interface
Format of Data/Findings
Test Track Testing
Test Track Facilities
Static Results
Dynamic Results
Multipath Considerations
Conclusions
33November 4th, 2003November 4th, 2003 Vehicle Safety Communications ConsortiumVehicle Safety Communications Consortium
Test Equipment
VSC VSC Communication Communication Test Kits (CTKs)Test Kits (CTKs)
Laptops with Laptops with 802.11a card802.11a card
DGPS receiversDGPS receivers Magmount DSRC Magmount DSRC
and DGPS and DGPS antennasantennas
Portable Portable implementationimplementation
44November 4th, 2003November 4th, 2003 Vehicle Safety Communications ConsortiumVehicle Safety Communications Consortium
CTK S/W v2.3CTK S/W v2.3 CTK S/W v2.7CTK S/W v2.7 DSRC StandardDSRC Standard
25/50 mW default 25/50 mW default antenna input power antenna input power settingssettings
Up to 100 mW Up to 100 mW programmable programmable antenna input powerantenna input power
Up to 750 mW variable Up to 750 mW variable antenna input powerantenna input power
5.15-5.35, 5.725-5.825 5.15-5.35, 5.725-5.825 GHzGHz
5.15-5.35, 5.725-5.15-5.35, 5.725-5.825, 5.85-5.925 GHz5.825, 5.85-5.925 GHz
5.85-5.925 GHz5.85-5.925 GHz
20 MHz channel20 MHz channel 10 MHz channel10 MHz channel 10 MHz channel10 MHz channel
Real-time rangeReal-time range Real-time rangeReal-time range N/AN/A
Unknown RSSIUnknown RSSI Real-time RSSIReal-time RSSI N/AN/A
Pre-set channelPre-set channel Selectable channelSelectable channel Channel switchingChannel switching
Diversity antennasDiversity antennas Diversity with manual Diversity with manual overrideoverride
N/AN/A
IEEE 802.11 Ad hocIEEE 802.11 Ad hoc DSRC Ad hocDSRC Ad hoc DSRC Ad hocDSRC Ad hoc
6-54 Mbps6-54 Mbps 3-27 Mbps3-27 Mbps 3-27 Mbps3-27 Mbps
CTK Configuration
55November 4th, 2003November 4th, 2003 Vehicle Safety Communications ConsortiumVehicle Safety Communications Consortium
CTK Sender Interface
Broadcast durationBroadcast duration Update rate Update rate Packet sizePacket size
dy1
dx1
66November 4th, 2003November 4th, 2003 Vehicle Safety Communications ConsortiumVehicle Safety Communications Consortium
CTK Receiver Interface
Packet numberPacket number OS/GPS timestampOS/GPS timestamp DGPS location DGPS location
coordinatescoordinates
dy1
dx1
77November 4th, 2003November 4th, 2003 Vehicle Safety Communications ConsortiumVehicle Safety Communications Consortium
OutlineOverview of Hardware and Software
Test Equipment and Interface
Format of Data/Findings
Test Track Testing
Test Track Facilities
Static Results
Dynamic Results
Multipath Considerations
Conclusions
88November 4th, 2003November 4th, 2003 Vehicle Safety Communications ConsortiumVehicle Safety Communications Consortium
Format of Data/Findings Received packets (in green)Received packets (in green) Lost packets (in red)Lost packets (in red)
Received packets (in green)Received packets (in green)
99November 4th, 2003November 4th, 2003 Vehicle Safety Communications ConsortiumVehicle Safety Communications Consortium
Format of Data/Findings Packet number on left axis Packet number on left axis Accumulated packets (in black)Accumulated packets (in black)
Packet number on left axis Packet number on left axis
1010November 4th, 2003November 4th, 2003 Vehicle Safety Communications ConsortiumVehicle Safety Communications Consortium
Format of Data/Findings Distance between antennas (in blue)Distance between antennas (in blue) Distance value on right axisDistance value on right axis
Distance between antennas (in blue)Distance between antennas (in blue)
1111November 4th, 2003November 4th, 2003 Vehicle Safety Communications ConsortiumVehicle Safety Communications Consortium
Effect of GPS satellite obstruction
1212November 4th, 2003November 4th, 2003 Vehicle Safety Communications ConsortiumVehicle Safety Communications Consortium
OutlineOverview of Hardware and Software
Test Equipment and Interface
Format of Data/Findings
Test Track Testing
Test Track Facilities
Static Results
Dynamic Results
Multipath Considerations
Conclusions
1313November 4th, 2003November 4th, 2003 Vehicle Safety Communications ConsortiumVehicle Safety Communications Consortium
Test Track Facilities
Controlled environmentControlled environment
Two-lane test roadTwo-lane test road
Straight-away with rural Straight-away with rural surroundingssurroundings
Overhead bridge can Overhead bridge can disrupt GPS signaldisrupt GPS signal
OverheadBridge
TestTrack
1414November 4th, 2003November 4th, 2003 Vehicle Safety Communications ConsortiumVehicle Safety Communications Consortium
OutlineOverview of Hardware and Software
Test Equipment and Interface
Format of Data/Findings
Test Track Testing
Test Track Facilities
Static Results
Dynamic Results
Multipath Considerations
Conclusions
x
y
z
v2v1
dy1
dx1
Sender
Receiver
Legend:
Two Static Antennas
1515November 4th, 2003November 4th, 2003 Vehicle Safety Communications ConsortiumVehicle Safety Communications Consortium
Two Static Antennas 200m range, 200 bytes, ~100 msec update rate200m range, 200 bytes, ~100 msec update rate Direct Line of Sight (LoS), no packet lossDirect Line of Sight (LoS), no packet loss
x
y
z
v1 v2
dy1
dx1
1616November 4th, 2003November 4th, 2003 Vehicle Safety Communications ConsortiumVehicle Safety Communications Consortium
Two Static Antennas Obstructed LoS (stationary SUVs)Obstructed LoS (stationary SUVs) No packet loss at various distancesNo packet loss at various distances
dy
1
dx1
1 2 3
1717November 4th, 2003November 4th, 2003 Vehicle Safety Communications ConsortiumVehicle Safety Communications Consortium
Two Static Antennas 35m range, obstructed LoS (large box truck)35m range, obstructed LoS (large box truck) Vehicles positioned laterally – no packet lossVehicles positioned laterally – no packet loss
x
y
zv2
v1
dy1
dx1
1818November 4th, 2003November 4th, 2003 Vehicle Safety Communications ConsortiumVehicle Safety Communications Consortium
Two Static Antennas 39m range, obstructed LoS (large box truck)39m range, obstructed LoS (large box truck) Positioned longitudinally – some loss of packetsPositioned longitudinally – some loss of packets
x
y
z
v2v1
dy1
1919November 4th, 2003November 4th, 2003 Vehicle Safety Communications ConsortiumVehicle Safety Communications Consortium
OutlineOverview of Hardware and Software
Test Equipment and Interface
Format of Data/Findings
Test Track Testing
Test Track Facilities
Static Results
Dynamic Results
Multipath Considerations
Conclusions
ffv2
x
y
z
dy1
dx1
(RSU)
1
Legend:
Sender
Receiver
One Dynamic Antenna (OBU)One Static Antenna (RSU)
Obstructer
2020November 4th, 2003November 4th, 2003 Vehicle Safety Communications ConsortiumVehicle Safety Communications Consortium
One Dynamic, One Static Antenna Receiving vehicle ~60 mphReceiving vehicle ~60 mph No packet lossNo packet loss
v1
dy1
dx1
x
yz
2121November 4th, 2003November 4th, 2003 Vehicle Safety Communications ConsortiumVehicle Safety Communications Consortium
One Dynamic, One Static Antenna Transmitting vehicle ~60 mphTransmitting vehicle ~60 mph A few lost packetsA few lost packets
v2
x
yz
dy1
dx1
(RSU)
2222November 4th, 2003November 4th, 2003 Vehicle Safety Communications ConsortiumVehicle Safety Communications Consortium
One Dynamic, One Static Antenna Transmitting vehicle ~20 mphTransmitting vehicle ~20 mph A few lost packetsA few lost packets
v2
xy
zdy1
dx1
(RSU)
2323November 4th, 2003November 4th, 2003 Vehicle Safety Communications ConsortiumVehicle Safety Communications Consortium
One Dynamic, One Static Antenna Receiving vehicle ~40 mph, with obstructionReceiving vehicle ~40 mph, with obstruction No packet lossNo packet loss
v1
dy1
dx1
2424November 4th, 2003November 4th, 2003 Vehicle Safety Communications ConsortiumVehicle Safety Communications Consortium
One Dynamic, One Static Antenna Transmitting vehicle ~40 mph, with obstructionTransmitting vehicle ~40 mph, with obstruction No packet lossNo packet loss
dy
f
v2
x
y
z
dy1
dx1
(RSU)
2525November 4th, 2003November 4th, 2003 Vehicle Safety Communications ConsortiumVehicle Safety Communications Consortium
OutlineOverview of Hardware and Software
Test Equipment and Interface
Format of Data/Findings
Test Track Testing
Test Track Facilities
Dynamic Results
Multipath Considerations
Static Results
Conclusions
v1v2
dy1
dx1
1
Legend:
Sender
Receiver
Obstructer
Two Dynamic Antennas (OBUs)
2626November 4th, 2003November 4th, 2003 Vehicle Safety Communications ConsortiumVehicle Safety Communications Consortium
Two Dynamic Antennas 2 vehicles ~ various speeds, same direction 2 vehicles ~ various speeds, same direction Distances up to 150 m, no packet lossDistances up to 150 m, no packet loss
x
y
z
v1v2
dy1
dx1
2727November 4th, 2003November 4th, 2003 Vehicle Safety Communications ConsortiumVehicle Safety Communications Consortium
Two Dynamic Antennas Various speeds, same direction, ~150 m rangeVarious speeds, same direction, ~150 m range Cut-in SUV, no packet lossCut-in SUV, no packet loss
v1v2
dy1
dx1
2828November 4th, 2003November 4th, 2003 Vehicle Safety Communications ConsortiumVehicle Safety Communications Consortium
Two Dynamic Antennas Sender vehicle and SUV brake to a stopSender vehicle and SUV brake to a stop Lost packets are likely due to SUV obstructionLost packets are likely due to SUV obstruction
dx
v1
v2
dy
(Comes to STOP)dx
v1
v2
dy
(Comes to STOP)dx
v1
v2
dy
(Comes to STOP)
2929November 4th, 2003November 4th, 2003 Vehicle Safety Communications ConsortiumVehicle Safety Communications Consortium
Two Dynamic Antennas Receiver passes sender braking from 30 – 0 mphReceiver passes sender braking from 30 – 0 mph Packet loss at ~ 90 mPacket loss at ~ 90 m
x
y
z
v1
v2
dy1
dx1
3030November 4th, 2003November 4th, 2003 Vehicle Safety Communications ConsortiumVehicle Safety Communications Consortium
Two Dynamic Antennas Sender and receiver pass at 50 mphSender and receiver pass at 50 mph ~50 msec, 400 bytes, no packet loss~50 msec, 400 bytes, no packet loss
x
y
z
v1
v2
dy1
dx1
3131November 4th, 2003November 4th, 2003 Vehicle Safety Communications ConsortiumVehicle Safety Communications Consortium
Two Dynamic Antennas Sender and receiver pass at 30 mphSender and receiver pass at 30 mph Packet loss at ~ 90 mPacket loss at ~ 90 m
x
y
z
v1
v2
dy1
dx1
3232November 4th, 2003November 4th, 2003 Vehicle Safety Communications ConsortiumVehicle Safety Communications Consortium
OutlineOverview of Hardware and Software
Test Equipment and Interface
Format of Data/Findings
Test Track Testing
Test Track Facilities
Static Results
Dynamic Results
Multipath Considerations
Conclusions
3333November 4th, 2003November 4th, 2003 Vehicle Safety Communications ConsortiumVehicle Safety Communications Consortium
Multipath Considerations
Two-Ray Ground Multipath ModelTwo-Ray Ground Multipath Model
EEtotal total = E= EDD + E+ ERR(e(ejj ))
EEmin min = E= EDD – E– ERR when when = = ππ
D: Direct Line of Sight
R: Reflected Line of Sight
3434November 4th, 2003November 4th, 2003 Vehicle Safety Communications ConsortiumVehicle Safety Communications Consortium
Multipath Considerations Null spot found through slow-rolling testNull spot found through slow-rolling test Loss of packets between ~ 87 m and 94 mLoss of packets between ~ 87 m and 94 m
Track entrance
SUV – sender stopped. Facing west
LeSabre - receiver driving on the shoulder towards
SUV.
Facing East.
overpass
West
3535November 4th, 2003November 4th, 2003 Vehicle Safety Communications ConsortiumVehicle Safety Communications Consortium
Multipath Considerations Steady state test at ~ 92 m null spotSteady state test at ~ 92 m null spot Almost complete loss of packetsAlmost complete loss of packets
v2v1
dy1
dx1
3636November 4th, 2003November 4th, 2003 Vehicle Safety Communications ConsortiumVehicle Safety Communications Consortium
Test Track Conclusions Single-sender, single-receiver DSRC under direct LoS Single-sender, single-receiver DSRC under direct LoS
conditions is robust for a variety of vehicle-vehicle and conditions is robust for a variety of vehicle-vehicle and vehicle-infrastructure safety applicationsvehicle-infrastructure safety applications
Some degree of packet loss, as expectedSome degree of packet loss, as expected Multipath transmissionsMultipath transmissions Vehicle obstructing LoSVehicle obstructing LoS
Range, update rate, and latency requirements for the Range, update rate, and latency requirements for the Task 3 safety applications should be feasibleTask 3 safety applications should be feasible
Areas for future study include:Areas for future study include: Transmission power variationTransmission power variation Multi-sender, multi-receiver scenariosMulti-sender, multi-receiver scenarios