1 / 36

Vehicle Safety Communications Project VSC Progress Briefing #2 – Task 4 Field Testing –

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

deidra
Download Presentation

Vehicle Safety Communications Project VSC Progress Briefing #2 – Task 4 Field Testing –

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. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript


  1. Vehicle Safety Communications Project VSC Progress Briefing #2 – Task 4 Field Testing – Overview of Hardware and Software Test Track Results

  2. 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

  3. Test Equipment • VSC Communication Test Kits (CTKs) • Laptops with 802.11a card • DGPS receivers • Magmount DSRC and DGPS antennas • Portable implementation

  4. CTK Configuration

  5. CTK Sender Interface • Broadcast duration • Update rate • Packet size

  6. CTK Receiver Interface • Packet number • OS/GPS timestamp • DGPS location coordinates

  7. 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

  8. Format of Data/Findings • Received packets (in green) • Received packets (in green) • Lost packets (in red)

  9. Format of Data/Findings • Packet number on left axis • Packet number on left axis • Accumulated packets (in black)

  10. Format of Data/Findings • Distance between antennas (in blue) • Distance between antennas (in blue) • Distance value on right axis

  11. Effect of GPS satellite obstruction

  12. 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

  13. Test Track Facilities Test Track • Controlled environment • Two-lane test road • Straight-away with rural surroundings • Overhead bridge can disrupt GPS signal Overhead Bridge

  14. 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

  15. 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

  16. Two Static Antennas • Obstructed LoS (stationary SUVs) • No packet loss at various distances

  17. Two Static Antennas • 35m range, obstructed LoS (large box truck) • Vehicles positioned laterally – no packet loss

  18. Two Static Antennas • 39m range, obstructed LoS (large box truck) • Positioned longitudinally – some loss of packets

  19. 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

  20. dx1 v1 f x dy1 z y One Dynamic, One Static Antenna • Receiving vehicle ~60 mph • No packet loss

  21. dx1 (RSU) v2 dy1 x z y One Dynamic, One Static Antenna • Transmitting vehicle ~60 mph • A few lost packets

  22. dx1 (RSU) v2 dy1 x z y One Dynamic, One Static Antenna • Transmitting vehicle ~20 mph • A few lost packets

  23. dy1 v1 f dx1 One Dynamic, One Static Antenna • Receiving vehicle ~40 mph, with obstruction • No packet loss

  24. One Dynamic, One Static Antenna • Transmitting vehicle ~40 mph, with obstruction • No packet loss

  25. 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

  26. Two Dynamic Antennas • 2 vehicles ~ various speeds, same direction • Distances up to 150 m, no packet loss

  27. Two Dynamic Antennas • Various speeds, same direction, ~150 m range • Cut-in SUV, no packet loss

  28. Two Dynamic Antennas • Sender vehicle and SUV brake to a stop • Lost packets are likely due to SUV obstruction

  29. Two Dynamic Antennas • Receiver passes sender braking from 30 – 0 mph • Packet loss at ~ 90 m

  30. Two Dynamic Antennas • Sender and receiver pass at 50 mph • ~50 msec, 400 bytes, no packet loss

  31. Two Dynamic Antennas • Sender and receiver pass at 30 mph • Packet loss at ~ 90 m

  32. 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

  33. 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

  34. 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

  35. Multipath Considerations • Steady state test at ~ 92 m null spot • Almost complete loss of packets

  36. 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

More Related