1. 11ax PAR Verification through OFDMA
November 2016
11ax PAR Verification through OFDMA
Date:
Authors:
Name
Affiliations
Address
Phone
Suhwook Kim
LG Electronics
19, Yangjea-daero 11gil, Seocho-gu, Seoul , Korea
Hyunhee Park
Jeongki Kim
Kiseon Ryu
HanGyu Cho
Suhwook Kim, LG Electronics

2. November 2016
Introduction
The goal of this contribution is to verify that the target of 11ax PAR is met
i.e. four times throughput enhancement
In contributions [1] – [10], we have addressed OFDMA performance based on PHY/MAC-integrated simulation
In September meeting, we addressed 26-tone RU, UL only traffic in Outdoor Scenario
We could achieve up to 15.4 times OFDMA throughput gain
Suhwook Kim, LG Electronics

3. Main update in the simulation
November 2016
Main update in the simulation
Previous submission
UL only traffic has been considered to exploit OFDMA gain in UL side
Only 2 BSSs scenario has been considered for OBSS case
Update in this submission
To verify OFDMA gain in more real field, we updated traffic mode and OBSS case
We consider DL/UL mixed traffic
Modified SS4 (7 BSSs in Outdoor Large BSS) is considered
Suhwook Kim, LG Electronics

4. Simulation Parameters
November 2016
Simulation Parameters
Simulator Type
PHY/MAC Integrated simulator
Tx Power (AP/STA)
30/15 dBm (SS4 default value)
Antenna Gain (AP/STA)
0/-2 dBi
RX sensitivity
-92 dBm
Traffic Model
UDP UL/DL mixed, Full buffer
BSS Bandwidth
80MHz
OFDMA parameter
37 RUs (26 tones), Random scheduler (1 RU for 1 STA)
EDCA parameter
Default AC_BE
MSDU size (bytes)
300
Feedback
GENIE
RTS/CTS
OFDMA: OFF, Legacy: ON
Max Retx 10
Symbol length
4 usec (legacy), 16usec (OFDMA)
Metrics
Throughput
Queue Size
MAC Queue: AP: 2000 * # of associated STA, STA: 2000
Suhwook Kim, LG Electronics

5. Simulation Setup for Single BSS
November 2016
Simulation Setup for Single BSS
Topology description
Number of STA: 37
STA location
15, 25, 35, 45, 55 meters from AP
Distribution of STA’s location: Next slide
Channel model
UMi, NLoS only
In OFDMA, DL and UL portion is 1:37 or 1:1
15 m
25 m
35 m
45 m
55 m
Suhwook Kim, LG Electronics

6. Simulation Cases for Single BSS
November 2016
Simulation Cases for Single BSS
Case 1: All STAs (37 STAs) are co-located
Case 1 – 1 : All STAs at 55 meters
Case 1 – 2 : All STAs at 45 meters
Case 1 – 3 : All STAs at 35 meters
Case 1 – 4 : All STAs at 25 meters
Case 1 – 5 : All STAs at 15 meters
DL / UL portion = 1 : 37
Case 2: 37 STAs are distributed in proportion to the square of distance
16 / 11 / 6 / 3 / 1 (55m / 45m / 35m / 25m / 15m)
DL / UL portion = 1 : 1
Suhwook Kim, LG Electronics

7. Simulation Setting: MCS and BW
November 2016
Simulation Setting: MCS and BW
In each distance, the best combination of MCS and transmission BW was selected
55 meter
45 meter
35 meter
25 meter
15 meter
Legacy DL
80 MHz, MCS 1
80 MHz, MCS 3
80 MHz, MCS 4
80 MHz, MCS 5
80 MHz, MCS 7 UL
20 MHz, MCS 0
40 MHz, MCS 0
80 MHz, MCS 0
OFDMA
MCS 3
MCS 4
MCS 6
MCS 8
Suhwook Kim, LG Electronics

8. Simulation Result for Case 1
November 2016
Simulation Result for Case 1
Sum Throughput
Suhwook Kim, LG Electronics

9. Simulation Result for Case 1
November 2016
Simulation Result for Case 1
DL Throughput
Suhwook Kim, LG Electronics

10. Simulation Result for Case 1
November 2016
Simulation Result for Case 1
UL Throughput
Suhwook Kim, LG Electronics

11. Simulation Result for Case 2
November 2016
Simulation Result for Case 2
Throughput of each STA
OFDMA gain: 3.7
(Sum Throughput
Legacy: Mbps
OFDMA: Mbps)
Suhwook Kim, LG Electronics

12. Discussion for Single BSS
November 2016
Discussion for Single BSS
If STAs are co-located at same distance,
UL OFDMA gain increases with distance between STA and AP
DL OFDMA gain is around 6 ~ 8 without distance between STA and AP
total OFDMA gain is larger than four times in every distance
If STAs are distributed in proportion to the square of distance,
near STAs get more TXOP and dominantly affect the overall performance in Legacy
OFDMA can achieve relatively even performance and more higher sum throughput
Suhwook Kim, LG Electronics

13. Simulation Setup for OBSS
November 2016
Simulation Setup for OBSS
Topology description
Modified SS4 (Outdoor Large BSS), ICD = 130 meters
STA location
Random in 15, 25, 35, 45, 55 meters ring from each home AP
Distribution is same with single BSS Case 2 (1 / 3 / 6 / 11 / 16)
MCS and BW: 1 level drop from single BSS simulation setting
Suhwook Kim, LG Electronics

14. Simulation Result for OBSS
November 2016
Simulation Result for OBSS
Throughput of each STA
OFDMA gain: 5.9
(Sum Throughput
Legacy: Mbps
OFDMA: Mbps)
Suhwook Kim, LG Electronics

15. Discussion for OBSS In OBSS Outdoor scenario,
November 2016
Discussion for OBSS
In OBSS Outdoor scenario,
OFDMA shows better throughput in every distance
only 15m and 25m STAs have over 1 Mbps throughput in legacy, but OFDMA can support over 1 Mbps throughput up to 55m
DL performance is very poor in legacy, but OFDMA can support appropriate DL performance
total OFDMA gain is over four times
Suhwook Kim, LG Electronics

16. November 2016
Conclusion
We verified that OFDMA can provide four times throughput enhancement in outdoor environment and DL/UL mixed traffic
More gain in OFDMA can be obtained e.g., by adopting a better scheduler than a random scheduler
Suhwook Kim, LG Electronics

17. November 2016
Reference
[1] ~ [10] 11-15/1095r0 ~ r10
[10] 11-14/0980r14 Simulation Scenarios
Suhwook Kim, LG Electronics

18. Appendix – Detail results
November 2016
Appendix – Detail results
Suhwook Kim, LG Electronics

19. Simulation Result for Case 1
November 2016
Simulation Result for Case 1
Case 1-1
(All STAs
at 55m)
Case 1-2
at 45m)
Case 1-3
at 35m)
Case 1-4
at 25m)
Case 1-5
at 15m)
Legacy
SUM
(DL/UL)
3.82 Mbps
(0.55 / 3.28)
7.99 Mbps
(0.57 / 7.41)
19.45 Mbps
(0.96 / 18.49)
36.97 Mbps
(1.62 / 35.35)
73.52 Mbps
(1.93 / 71.59)
OFDMA
71.78 Mbps
(3.62 / 68.16)
95.97 Mbps
(4.90 / 91.08)
Mbps
(5.55 / )
Mbps
(9.33 / )
Mbps
(11.42 / )
OFDMA gain
18.8
(6.6 / 20.8)
12.0
(8.6 / 12.3)
7.2
(5.8 / 7.3)
5.5
(5.8 / 5.5)
4.1
(5.9 / 4.0)
Suhwook Kim, LG Electronics

20. Simulation Result for Case 2
November 2016
Simulation Result for Case 2
55 meter
45 meter
35 meter
25 meter
15 meter
Number of STA 16 11 6 3 1
Legacy
SUM
24.89 Mbps
(0.71 / 24.18)
a STA (DL/UL)
0.01 / 0.07
0.02 / 0.12
0.03 / 0.54
0.03 / 3.59
0.03 / 7.77
OFDMA
92.92 Mbps
(54.75 / 38.17)
a STA
(DL/UL)
1.22 / 0.62
1.63 / 0.81
1.74 / 1.53
1.75 / 2.28
1.69 / 3.23
OFDMA gain
3.7
Suhwook Kim, LG Electronics

21. Simulation Result for OBSS
November 2016
Simulation Result for OBSS
55 meter
45 meter
35 meter
25 meter
15 meter
Number of STA 16 11 6 3 1
Legacy
SUM
11.35 Mbps
(0.15 / 11.20)
a STA (DL/UL)
0.003 / 0.05
0.003 / 0.14
0.006 / 0.50
0.008 / 1.42
0.008 / 1.65
OFDMA
67.33 Mbps
(34.81 / 32.52)
a STA
(DL/UL)
0.50 / 0.51
0.90 / 0.75
1.19 / 1.21
1.42 / 2.15
1.65 / 3.34
OFDMA gain
5.9
Suhwook Kim, LG Electronics