1. EDCA Parameters for WAVE
Month Year
doc.: IEEE yy/xxxxr0
May 2007
EDCA Parameters for WAVE
Date:
Authors:
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Justin McNew – TechnoCom
John Doe, Some Company

2. Month Year
doc.: IEEE yy/xxxxr0
May 2007
Abstract
This presentation answers p draft comments about the EDCA parameters for use in a WBSS that are shown in Table p4. Simulation results will be presented which show that the parameters are optimum and give good performance for more than 200 vehicles.
Justin McNew – TechnoCom
John Doe, Some Company

3. Overview General simulation description
Month Year
doc.: IEEE yy/xxxxr0
May 2007
Overview
General simulation description
Simulation scenarios and results
EDCA parameter optimization (verification of Table p4)
Simulation for more than 200 vehicles
Justin McNew – TechnoCom
John Doe, Some Company

4. Simulation Platform NS-2 version 2.29
Month Year
doc.: IEEE yy/xxxxr0
May 2007
Simulation Platform
NS-2 version 2.29
802.11e module added
TechnoCom-developed WAVE/DSRC modules added
TechnoCom-developed pre- and post-processing software
Justin McNew – TechnoCom
John Doe, Some Company

5. General Simulation Setup
Month Year
doc.: IEEE yy/xxxxr0
May 2007
General Simulation Setup
OBUs are arranged in a rectangular array in simulated space
Each OBU broadcasts messages of a fixed AC on the CCH every 100 ms
Each OBU is within range of every other OBU
Justin McNew – TechnoCom
John Doe, Some Company

6. General Simulation Setup
Month Year
doc.: IEEE yy/xxxxr0
May 2007
General Simulation Setup
LL OBU transmission range
UL OBU transmission range
UR OBU transmission range
LR OBU transmission range
= OBU LR LL UL UR
Justin McNew – TechnoCom
John Doe, Some Company

7. Scenario 1: EDCA Parameter Optimization
Month Year
doc.: IEEE yy/xxxxr0
May 2007
Scenario 1: EDCA Parameter Optimization
Addresses 11p draft comments such as 418
Simulations were performed in 12/2006 for VIIC Proof of Concept system
150 simulated OBUs in the array
Vary AIFSN, CWmin, CWMax
Compare message delivery success rate (MDSR) and packet latency for each AC
Optimization criteria
Higher-priority messages should be received faster
Packet latencies should be minimum
Justin McNew – TechnoCom
John Doe, Some Company

8. Scenario 1 Results May 2007 Month Year doc.: IEEE 802.11-yy/xxxxr0
200 byte packets, one OBU at AC = 3 (1%), 6 at AC =2 (4%), 23 at AC =1 (15%) and 120 at AC = 0 (80%)
Justin McNew – TechnoCom
John Doe, Some Company

9. Scenario 1 Results May 2007 Month Year doc.: IEEE 802.11-yy/xxxxr0
400 byte packets, one OBU at AC = 3 (1%), 6 at AC =2 (4%), 23 at AC =1 (15%) and 120 at AC = 0 (80%)
Justin McNew – TechnoCom
John Doe, Some Company

10. Scenario 1 Results May 2007 Month Year doc.: IEEE 802.11-yy/xxxxr0
200 byte packets, 3 OBUs at AC = 3 (2%), 5 at AC =2 (3%), 7 at AC =1 (5%) and 135 at AC = 0 (90%)
Justin McNew – TechnoCom
John Doe, Some Company

11. Scenario 1 Results May 2007 Month Year doc.: IEEE 802.11-yy/xxxxr0
400 byte packets, 3 OBUs at AC = 3 (2%), 5 at AC =2 (3%), 7 at AC =1 (5%) and 135 at AC = 0 (90%):
Justin McNew – TechnoCom
John Doe, Some Company

12. Scenario 1 Results May 2007 Month Year doc.: IEEE 802.11-yy/xxxxr0
200 byte packets, 15 OBUs at AC = 3 (10%), 30 at AC =2 (20%), 45 at AC =1 (30%) and 60 at AC = 0 (40%)
Justin McNew – TechnoCom
John Doe, Some Company

13. Scenario 1 Results May 2007 Month Year doc.: IEEE 802.11-yy/xxxxr0
400 byte packets, 15 OBUs at AC = 3 (10%), 30 at AC =2 (20%), 45 at AC =1 (30%) and 60 at AC = 0 (40%):
Justin McNew – TechnoCom
John Doe, Some Company

14. Scenario 1 Results May 2007 Month Year doc.: IEEE 802.11-yy/xxxxr0
200 byte packets, 37 OBUs at AC = 3 (25%), 38 at AC =2 (25%), 37 at AC =1 (25%) and 38 at AC = 0 (25%)
Justin McNew – TechnoCom
John Doe, Some Company

15. Scenario 1 Results May 2007 Month Year doc.: IEEE 802.11-yy/xxxxr0
400 byte packets, 37 OBUs at AC = 3 (25%), 38 at AC =2 (25%), 37 at AC =1 (25%) and 38 at AC = 0 (25%)
Justin McNew – TechnoCom
John Doe, Some Company

16. Month Year
doc.: IEEE yy/xxxxr0
May 2007
Scenario 1 Conclusions
The results verify that the parameters given in Table p4 (also the first row in each of the preceding results tables) give the best compromise among the optimization criteria.
Good prioritization even at low channel loading
Good message delivery success rate throughout the ACs
Reasonable packet latencies, even at high loading and low priorities
Justin McNew – TechnoCom
John Doe, Some Company

17. Scenario 1 Conclusions May 2007 Month Year doc.: IEEE 802.11-yy/xxxxr0AC
CWmin
CWmax
AIFSN
TXOP Limit
OFDM PHY
(WAVE mode)
AC_BK
aCWmin = 15
aCWmax = 1023 9
AC_BE
(aCWmin+1)/2 – 1 = 7 6
AC_VI
(aCWmin+1)/4 – 1 = 3 3
AC_VO 2
Justin McNew – TechnoCom
John Doe, Some Company

18. Scenario 2: More than 200 Vehicles
Month Year
doc.: IEEE yy/xxxxr0
May 2007
Scenario 2: More than 200 Vehicles
Simulations were performed in 5/2007 to address 11p draft comments such as 415, 420, etc.
Set AIFSN, CWmin, CWMax as in Table p4
200 byte packets
Vary the total number of simulated OBUs in the array
Same number of OBUs for each AC (i.e. 25% of the OBUs are broadcasting highest priority messages)
Justin McNew – TechnoCom
John Doe, Some Company

19. Highest priority (AC = AC_VO) messages
Month Year
doc.: IEEE yy/xxxxr0
May 2007
Scenario 2 Results
Number of vehicles
Highest priority (AC = AC_VO) messages
MDSR (%)
Mean latency (ms)
Max latency (ms)
250 85
0.4
1.3
300 78
1.5
350 75
0.5
1.7
Justin McNew – TechnoCom
John Doe, Some Company

20. Month Year
doc.: IEEE yy/xxxxr0
May 2007
Scenario 2 Conclusions
The results verify that the parameters given in Table p4 give good results for more than 200 vehicles
Message delivery success rate is good, despite small contention window
Packet latencies are good
Justin McNew – TechnoCom
John Doe, Some Company