This presentation describes the architecture and functionality of a newly designed hopping algorithm that can disseminate messages on desired route(s) only using vehicle to vehicle (V2V) communication

1. Department of Electrical Engineering
TRAFFIC INFORMATION SYSTEM TO DELIVER
IN-VEHICLE MESSAGES ON PRE-DEFINED
ROUTES USING DSRC BASED V2V
COMMUNICATION
Attiq Uz Zaman
M.I. Hayee
University of Minnesota Duluth
Navin Katta
Sean Mooney
Savari Inc.

2. Department of Electrical Engineering
Motivation
• 579 deaths due to work zones in
2013
• Work zones constituted to $700
million in fuel loss
• 12% of all delay on freeways Is
caused due to work zones.

3. Department of Electrical Engineering
Outline
• Introduction
• Hopping algorithm
• Simulation and results
• Preliminary field tests and future work
• Summary

4. Department of Electrical Engineering
Introduction
Work zones lane closure can cause congestion
to build up.
Intelligent Traffic Information Systems can help.
Main objectives of a traffic information system
 Gather dynamic traffic parameters e.g.,
travel time, back of the queue etc.
 Disseminate these parameters to the
vehicles approaching the congestion.
 DSRC a preferred choice due to its low latency
and highly secure protocol

5. Department of Electrical Engineering
Overall System and Challenges
RSU’s broadcast range is not enough to directly reach far off vehicles
Desired Region
RSU
Start of Work
Zone
End of work
zone
Hopping distance should be maximized without causing broadcast storm
Strict hopping route should be followed
OBUs don’t need to modify original message
Varying Starting
Location of Congestion
Range of RSU

6. Department of Electrical Engineering
RSU M = 1
End of work
zone
Smaller rectangles for
curved paths
Longer Rectangles for
straight paths
Pre-Defined Route
Start of Work
Zone
Desired Region
OBUs outside the rectangular
regions recognize msg not intended
for them

7. Department of Electrical Engineering
• Each Rectangle is virtually sub-divided into multiple sub-rectangles
• Each sub-rectangle is less than or equal to 250 m in length.
Hopping Windows
RSU M = 1
M = 4
N = 1 N = 2 N = 3 N = 4
- - - - - - - - - - - - - - - - - - - - - - - -
N = NM
L1-4 ≈ 250 m
L1
Length of Rectangles more than range of DSRC

8. Department of Electrical Engineering
Hop Timing control
N = 1 N = 2 N = 3 N = 7N = 4 N = 5 N = 6
Hopping time windows
(msec.)
RSU M = 1
M = 4
L1
‘b’ will hop before ‘a’ ‘d’ didn’t receive
100 – 200 200 – 300 300 – 400 400 - 500 500 – 600 600 – 700 700 – 800
200 msec
0 m
100 msec Distance from beginning of
main-rectangle
HoppingTimes
300 msec
400 msec
250 m 500 m 750 m

9. Department of Electrical Engineering
Hop Timing control
g ih jfd eca b
Hopping time windows
(msec.)
RSU M = 1
M = 4
L1
‘b’ will hop before ‘a’
100 – 200 200 – 300 300 – 400 400 - 500 500 – 600 600 – 700 700 – 800
RSU

10. Department of Electrical Engineering
Hop Timing control
g ih jfd eca b
Hopping time windows
(msec.)
RSU M = 1
M = 4
L1
‘a’ stops hopping process after receiving message from ‘b’
100 – 200 200 – 300 300 – 400 400 - 500 500 – 600 600 – 700 700 – 800
RSU

11. Department of Electrical Engineering
Hop Timing control
g ih jfd eca b
Hopping time windows
(msec.)
RSU M = 1
M = 4
L1
‘b’ will hop before ‘a’ ‘d’ didn’t receive
100 – 200 200 – 300 300 – 400 400 - 500 500 – 600 600 – 700 700 – 800
RSU

12. Department of Electrical Engineering
Hop Timing control
g ih jfd eca b
Hopping time windows
(msec.)
RSU M = 1
M = 4
L1
‘d’ will not hop message since it received this msg inside its hopping window
100 – 200 200 – 300 300 – 400 400 - 500 500 – 600 600 – 700 700 – 800
RSU

13. Department of Electrical Engineering
DSRC Specific Timing Control Issue
• 100 msec divided into control and service windows of 50 msec. each
• TIM is received/sent only in service window
0 10 20 30 40 50 60 70 80 90 100
IEEE 1609.4 standard
Control channel interval Service channel interval
0 10 20 30 40 50 60 70 80 90 100
Non IEEE 1609.4 standard
Full window available

14. Department of Electrical Engineering
a b
250 m
200 ms
Full window
available
b hops
100 ms
A does not
hop
DSRC Specific Hop Timing Control Solution
cRSU
200 ms
Service window
available
Control window100 ms Service window150 ms 250 ms
250 ms150 ms
100 msec
200 msec
0 m 250 m
Distance
HoppingTime
150 msec

15. Department of Electrical Engineering
Sub-rectangle And Hopping Time
Calculations
))(1.0())1.0)(((__
1
1
NiN=LimitTimeLower
M
i M 


)1.0(
250
250)1((
1.0 


ND
LTL=HWT M






250
M
M
L
ceil=N (1)
M
M
SRM
N
L
=L (2)






SRM
M
L
D
ceil=N (3)
05.))(1.0())1.0)(((__
1
1



NiN=LimitTimeLower
M
i M
)05.0(
250
250)1((
1.0 


ND
LTL=HWT M
DSRC specific hopping time calculation
Hopping time calculationSub-rectangle calculation

16. Department of Electrical Engineering
Simulation Setup
OBU 6
OBU 7
OBU 8
N = 1 N = 2 N = 3 N = 3 N = 4 N = 5N = 4 N = 1 N = 2 N = 6
OBU 1 OBU 2 OBU 3 OBU 4 OBU 5 OBU 9 OBU 10 OBU 12OBU 11
https://maps.google.com/
M = 2M = 1
Roadside unit
 We chose the West Arrowhead Road in Duluth, MN for simulation and preliminary field tests
 Total length of road segment is about 2.5 Km
 Twelve distinct points (latitude, longitude pair) were selected as potential OBU positions
 Two rectangles of length 1.5 and 1 Km each were used to cover the road segment.

17. Department of Electrical Engineering
OBU
No.
Distance from
roadside unit
(m)
LTL-UTL
(msec)
TIME at which TIM
is received
(msec)
TIME at which TIM
is supposed to
hop
(msec)
TIM hopped?
(Yes/No)
1 240 150-199 0.0 152 Yes
2 490 250-299 152 251 Yes
3 725 350-399 251 353 Yes
4 990 450-499 353 451 Yes
5 1200 550-599 451 558 Yes
6 1425 650-699 558 664 No (TIM hopped by OBU
#7 at 650 msec)
7 1495 650-699 558 650 Yes
8 Not Applicable NA 650 Not Applicable No (OBU is not on the
predefined route)
9 1740 750-799 650 751 Yes
OBU 6
OBU 7
OBU 8
N = 1 N = 2 N = 3 N = 3 N = 4 N = 5N = 4 N = 1 N = 2 N = 6
OBU 1 OBU 2 OBU 3 OBU 4 OBU 5 OBU 9 OBU 10 OBU 12OBU 11
Simulation Results

18. Department of Electrical Engineering
OBU 3OBU 2OBU 1RSU
PCMS
1.2 Km
Preliminary Road Tests
• 1 RSU and 3 OBUs placed on west arrowhead road Duluth
• Hopped TIM to 1.2 Km distance

19. Department of Electrical Engineering
Summary
 A traffic information system is designed which
 Disseminate messages on a desired route(s) using V2V communication
 Avoids broadcast storm
 Working on acquiring dynamic traffic parameters from the incoming vehicles
and on a GUI for dashboard display panel

20. Department of Electrical Engineering
Thank You
Attiq Uz Zaman
zaman013@d.umn.edu
Department of Electrical Engineering
University of Minnesota Duluth