1. System Performance Results for Scenario 1
Santosh Abraham, Arnaud Meylan, Sanjiv Nanda
Qualcomm, Inc.

2. Simulation Methodology
July 12-16, 2004
Simulation Methodology
The simulator is based on ns2
Includes physical layer features
TGn Channel Models
PHY Abstraction determines frame loss events
MAC features
EDCA
Adaptive Coordination Function (ACF): SCHED and SCAP
Frame Aggregation
ARQ with Block Ack
Closed Loop Rate Control (DRVF and DRV)
MIMO Modes (ES and SS)
Transport
File Transfer mapped to TCP
QoS Flows mapped to UDP

3. Structure of the Simulator
July 12-16, 2004
Structure of the Simulator

4. Layered Structure for 802.11 Simulation
July 12-16, 2004
Layered Structure for Simulation

5. Statistics Obtained Throughput: For each flow denote Mean Delay:
July 12-16, 2004
Statistics Obtained
Throughput:
As defined in CC 20. Throughput Metric 2.
For each flow denote
tl: Time at which the last packet is transferred to the receiver LLC
tf: Time at which the first packet arrives at the sender MAC SAP
N: Number of packets delivered within the delay bound to the receiver LLC by tl
p: Packet size.
Flow Throughput =
Mean Delay:
Mean of the time taken from packet arrival at the sender to packet arrival at the receiver across all packets of the flow.

6. Statistics Obtained Packet Loss Rate: As defined in CC 19
July 12-16, 2004
Statistics Obtained
Packet Loss Rate:
As defined in CC 19
Number of MSDUs that are not delivered at the Rx MAC SAP within the specified delay bound, divided by the total number of MSDUs offered at the Tx MAC SAP
Reasons for a packet being dropped are:
Delay incurred by the packet exceeds the delay tolerance of the flow. Delay is inclusive of scheduling and retransmission attempts.
Packet has not been delivered after a maximum number of transmission attempts.

7. Statistics Obtained Mean PHY Rate: As defined in CC 27:
July 12-16, 2004
Statistics Obtained
Mean PHY Rate:
As defined in CC 27:
N: Number of packets transmitted.
ri: PHY Transmission rate of ith packet.
ti: Transmission time of the ith packet
Mean PHY Rate =

8. Simulation Scenarios Modified TGn Usage Models Scenario 1
July 12-16, 2004
Simulation Scenarios
Modified TGn Usage Models Scenario 1
Channel Model B
Scenario 1 HT (High Throughput)
Increased Offered Non-QoS Load.
Additional 25 Mbps Internet file transfer at 15.5 m for 2x2
Additional 100 Mbps Internet file transfer at 15.5 m for 4x4
Scenario 1 LD (Low Delay)
Reduce all multimedia application delays to 50 ms.
Scenario 1 IR (Increased Range)
HDTV receivers moved to 25 m (instead of 5 m)

9. Simulation Conditions
July 12-16, 2004
Simulation Conditions
Simulation Parameters Alternate values considered in italics
ACF and EDCA
Frame Aggregation
Block ACK (Delayed ACK)
Highest MCS: 7 bits/symbol. Also considered 5 bits/symbol
All links: 2x2. Also considered 4x4.
5.25 GHz
EDCA Parameters

10. Performance Metrics Per flow Per scenario Throughput
July 12-16, 2004
Performance Metrics
Per flow
Throughput
Packet loss rate (PLR)
Mean delay
Time-averaged PHY data rate
Per scenario
Total throughput,
Latency of QoS flows,
Throughput for non-QoS flows
MAC Efficiency

11. Scenario 1 HT (High Throughput)
July 12-16, 2004
MAC Mode
MAC Efficiency
Total Throughput
QoS Flows Latency and Packet Loss Rate (PLR)
Non-QoS Throughput
Scenario 1 HT (High Throughput)
ACF
0.77
107.27
HDTV/SDTV mean delay < 18 ms Gaming PLR ~ 10^-3
55.42
EDCA with Frame Aggr
0.46
59.42
HDTV/SDTV mean delay < 10 ms Gaming PLR > 10%
MP3 PLR ~ 10^-3
7.40
Scenario 1 LD (Low delay)
ACF
0.76
103.53
HDTV/SDTV mean delay < 10 ms Gaming PLR ~ 10^-3
51.64
EDCA with Frame Aggr
0.48
60.40
HDTV/SDTV PLR ~ 10^-3
Gaming PLR > 10%
MP3 PLR ~ 10%
8.46
Scenario 1 IR (Increased Range)
ACF
0.76
93.57
HDTV/SDTV mean delay < 10 ms
SDTV PLR ~ 10^-3
Gaming & VOD Ctrl PLR ~ 10^-3
41.69
EDCA with Frame Aggr
0.56
59.15
HDTV/SDTV PLR ~ 10^-3
Gaming PLR > 10%
MP3 PLR > 10%
7.24

12. Scenario 1 IR Using ACF: Per Flow Results
July 12-16, 2004
Scenario 1 IR Using ACF: Per Flow Results

13. Scenario 1 IR 2x2 Scenario 1 IR 4x4 MAC Mode MAC Efficiency
July 12-16, 2004
MAC Mode
MAC Efficiency
Total Throughput
QoS Flows Latency and Packet Loss Rate (PLR)
Non-QoS Throughput
Scenario 1 IR 2x2
ACF
0.76
93.57
HDTV/SDTV mean delay < 10 ms
SDTV PLR ~ 10^-3
Gaming & VOD Ctrl PLR ~ 10^-3
41.69
EDCA with Frame Aggr
0.56
59.15
HDTV/SDTV PLR ~ 10^-3
Gaming PLR > 10%
MP3 PLR > 10%
7.24
Scenario 1 IR 4x4
ACF
0.74
190.17
HDTV/SDTV mean delay < 10 ms Gaming PLR ~ 10^-3
138.27
EDCA with Frame Aggr
0.35
70.44
HDTV/SDTV PLR ~ 10^-3
Gaming PLR > 10%
MP3 PLR ~ 5%
18.46

14. Scenario 1 HT Maximum 5 bits/symbol
July 12-16, 2004
MAC Mode
MAC Efficiency
Total Throughput
QoS Flows Latency and Packet Loss Rate (PLR)
Non-QoS Throughput
Scenario 1 HT Maximum 5 bits/symbol
ACF
0.78
90.62
HDTV/SDTV mean delay < 20 ms
38.75
EDCA with Frame Aggr
0.52
59.93
HDTV/SDTV mean delay < 10 ms Gaming PLR> 10%
Video CTRL ~ 10^-2
7.97
Scenario 1 LD Maximum 5 bits/symbol
ACF
0.75
86.74
HDTV/SDTV mean delay <10 ms
SDTV PLR ~10^-4
34.85
EDCA with Frame Aggr
0.53
60.98
HDTV/SDTV PLR ~ 10^-3
VoIP PLR ~ 10%
Gaming and MP3 PLR > 10%
9.00
Scenario 1 IR Maximum 5 bits/symbol
ACF
0.76
79.48
HDTV/SDTV mean delay < 10 ms
SDTV & Gaming PLR ~ 10^-3
27.61
EDCA with Frame Aggr
0.59
58.51
HDTV/SDTV PLR ~ 10^-2
Gaming and MP3 PLR > 10%
VoIP PLR < 10%
6.65

15. Conclusions from Scenario 1 Study
July 12-16, 2004
Conclusions from Scenario 1 Study
TGn Usage Models Scenario 1 requirements can be met and exceeded with 2x2.
Using Scheduled operation:
MAC Efficiency is in the range 74%-78%.
Scenario 1 HT: Throughput can be increased to above 100 Mbps
Scenario 1 LD: Video stream latency can be reduced below 50 ms (from 200 ms). Total throughput: 103 Mbps
Scenario 1 IR: Range of HDTV flows can be increased from 5 m to 25 m. Total throughput: 92 Mbps
MAC Efficiency of EDCA with Frame Aggregation is around 56% for 2x2 and falls to 35% for 4x4.
Throughput with 256 QAM
~15% throughput improvement with 256 QAM
By setting Maximum MCS=5 bits/symbol obtain Mbps for IR, LD, HT.