Vehicle Safety Communications Project
Download
1 / 36

Vehicle Safety Communications Project VSC Progress Briefing #2 – Task 4 Field Testing – - PowerPoint PPT Presentation


  • 43 Views
  • Uploaded on

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

loader
I am the owner, or an agent authorized to act on behalf of the owner, of the copyrighted work described.
capcha
Download Presentation

PowerPoint Slideshow about ' Vehicle Safety Communications Project VSC Progress Briefing #2 – Task 4 Field Testing –' - madelyn-sapphire


An Image/Link below is provided (as is) to download presentation

Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author.While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server.


- - - - - - - - - - - - - - - - - - - - - - - - - - E N D - - - - - - - - - - - - - - - - - - - - - - - - - -
Presentation Transcript

Vehicle Safety Communications Project

VSC Progress Briefing #2

– Task 4 Field Testing –

Overview of Hardware and Software

Test Track Results


Outline
Outline

Overview 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


Test equipment
Test Equipment

  • VSC Communication Test Kits (CTKs)

    • Laptops with 802.11a card

    • DGPS receivers

    • Magmount DSRC and DGPS antennas

    • Portable implementation



CTK Sender Interface

  • Broadcast duration

  • Update rate

  • Packet size


Ctk receiver interface
CTK Receiver Interface

  • Packet number

  • OS/GPS timestamp

  • DGPS location coordinates


Outline

Overview 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


Format of data findings
Format of Data/Findings

  • Received packets (in green)

  • Received packets (in green)

  • Lost packets (in red)


Format of data findings1
Format of Data/Findings

  • Packet number on left axis

  • Packet number on left axis

  • Accumulated packets (in black)


Format of Data/Findings

  • Distance between antennas (in blue)

  • Distance between antennas (in blue)

  • Distance value on right axis



Outline

Overview 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


Test Track Facilities

Test

Track

  • Controlled environment

  • Two-lane test road

  • Straight-away with rural surroundings

  • Overhead bridge can disrupt GPS signal

Overhead

Bridge


Outline

Overview 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

v

v

1

2

d

x1

d

y1

x

z

y

Two Static Antennas

Legend:

Sender

Receiver


Two static antennas

v1

v2

dx1

x

dy1

z

y

Two Static Antennas

  • 200m range, 200 bytes, ~100 msec update rate

  • Direct Line of Sight (LoS), no packet loss


Two static antennas1
Two Static Antennas

  • Obstructed LoS (stationary SUVs)

  • No packet loss at various distances


Two static antennas2
Two Static Antennas

  • 35m range, obstructed LoS (large box truck)

  • Vehicles positioned laterally – no packet loss


Two static antennas3
Two Static Antennas

  • 39m range, obstructed LoS (large box truck)

  • Positioned longitudinally – some loss of packets


Outline

Overview 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

d

x1

v

(RSU)

2

f

f

d

y1

x

z

y

One Dynamic Antenna (OBU)One Static Antenna (RSU)

1

Legend:

Sender

Receiver

Obstructer


One dynamic one static antenna

dx1

v1

f

x

dy1

z

y

One Dynamic, One Static Antenna

  • Receiving vehicle ~60 mph

  • No packet loss


One dynamic one static antenna1

dx1

(RSU)

v2

dy1

x

z

y

One Dynamic, One Static Antenna

  • Transmitting vehicle ~60 mph

  • A few lost packets


One dynamic one static antenna2

dx1

(RSU)

v2

dy1

x

z

y

One Dynamic, One Static Antenna

  • Transmitting vehicle ~20 mph

  • A few lost packets


One dynamic one static antenna3

dy1

v1

f

dx1

One Dynamic, One Static Antenna

  • Receiving vehicle ~40 mph, with obstruction

  • No packet loss


One dynamic one static antenna4
One Dynamic, One Static Antenna

  • Transmitting vehicle ~40 mph, with obstruction

  • No packet loss


Outline

Overview 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

Two Dynamic Antennas (OBUs)

1

Legend:

Sender

Receiver

Obstructer


Two dynamic antennas
Two Dynamic Antennas

  • 2 vehicles ~ various speeds, same direction

  • Distances up to 150 m, no packet loss


Two dynamic antennas1
Two Dynamic Antennas

  • Various speeds, same direction, ~150 m range

  • Cut-in SUV, no packet loss


Two dynamic antennas2
Two Dynamic Antennas

  • Sender vehicle and SUV brake to a stop

  • Lost packets are likely due to SUV obstruction


Two dynamic antennas3
Two Dynamic Antennas

  • Receiver passes sender braking from 30 – 0 mph

  • Packet loss at ~ 90 m


Two Dynamic Antennas

  • Sender and receiver pass at 50 mph

  • ~50 msec, 400 bytes, no packet loss


Two dynamic antennas4
Two Dynamic Antennas

  • Sender and receiver pass at 30 mph

  • Packet loss at ~ 90 m


Outline

Overview 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


Multipath considerations
Multipath Considerations

  • Two-Ray Ground Multipath Model

  • Etotal = ED+ ER(ej)

  • Emin = ED– ER when  = π

D: Direct

Line of Sight

R: Reflected

Line of Sight


Multipath considerations1
Multipath Considerations

  • Null spot found through slow-rolling test

  • Loss of packets between ~ 87 m and 94 m

West

overpass

LeSabre

-

receiver

driving on the

shoulder towards

SUV.

Facing East.

SUV

sender

stopped.

Facing west

Track entrance


Multipath considerations2
Multipath Considerations

  • Steady state test at ~ 92 m null spot

  • Almost complete loss of packets


Test track conclusions
Test Track Conclusions

  • Single-sender, single-receiver DSRC under direct LoS conditions is robust for a variety of vehicle-vehicle and vehicle-infrastructure safety applications

  • Some degree of packet loss, as expected

    • Multipath transmissions

    • Vehicle obstructing LoS

  • Range, update rate, and latency requirements for the Task 3 safety applications should be feasible

  • Areas for future study include:

    • Transmission power variation

    • Multi-sender, multi-receiver scenarios


ad