1. Simulation results for
November 2014
Simulation results for
Box 5 calibration
Date:
Authors:
Name
Affiliations
Address
Phone
Suhwook Kim
LG Electronics
19, Yangjea-daero 11gil, Seocho-gu, Seoul , Korea
Wookbong Lee
Giwon Park
Jeongki Kim
Kiseon Ryu
HanGyu Cho
Suhwook Kim, LG Electronics

2. November 2014
Abstract
This submission provides simulation results for Box-5 calibration
Simulation setting and all parameters are based on 1177r2 which was presented in September meeting
We observed key calibration point from simulation result and share it in this submission
Suhwook Kim, LG Electronics

3. Box-5 Calibration [1] Box 0, 1, and 2 calibration are almost done
November 2014
Box-5 Calibration [1]
Box 0, 1, and 2 calibration are almost done
Box 3 calibration is now in progress
Box 5 calibration was initially discussed in previous meeting
Box 5: Integrated system simulator calibration
The objective is to align a combination of all PHY and MAC features
Suhwook Kim, LG Electronics

4. Box-5 PHY Details [2] November 2014 PHY parametersBW
All BSSs at 5GHz [80 MHz, no dynamic bandwidth]
Channel model
TGac D NLOS per link
Shadow fading
iid log-normal shadowing (5 dB standard deviation) per link
Data Preamble Type
[5GHz, 11ac], always decoded correctly after successful reception, duration is considered.
STA TX Power
15 dBm per antenna 
AP TX Power
20 dBm  per antenna
AP number of TX/RX antennas
1/1
STA number of TX /RX antennas
AP antenna gain
0 dBi
STA antenna gain
-2 dBi
Noise Figure
7dB
CCA threshold
-70dBm (measured across the entire bandwidth after large-scale fading)
Rx sensitivity
-82dBm (a packet with lower rx power is dropped)
Link Adaption
Fixed MCS =7 (292.5 Mbps)
Channel estimation
ideal
PHY abstraction
RBIR, BCC [1, 5]
Channel correlation
Independent or time-correlated channel per packet
Suhwook Kim, LG Electronics

5. Box-5 MAC Details [2] November 2014 100 drops per simulation
MAC parameters
Access protocol
[EDCA, AC_BE with default parameters] [CWmin = 15, CWmax = 1023, AIFSn=3 ]
Queue length
A single queue for each traffic link is set inside AP/STA sized of 2000 packets
Traffic type
UDP CBR with rate 10^8bps (may not enough to model full buffer)
MPDU size
1540 Bytes (1472 Data + 28 IP header + 40 MAC header)
Aggregation
[A-MPDU / max aggregation size / BA window size, No A-MSDU, with immediate BA], Max aggregation: 64 MPDUs with 4-byte MPDU delimiter and 2-byte padding
Max number of retries 10
Beacon
Disabled
RTS/CTS
OFF
Traffic direction
UL Only, DL only, Mixed DL & UL
Throughput metric
CDF or Histogram of per non-AP STA throughput (received bits/overall simulation time)
100 drops per simulation
1 drop = 5 seconds (+ 1 second for initial running)
Suhwook Kim, LG Electronics

6. 11ac Scenario 6 – OBSS Enterprise [2][3]
November 2014
11ac Scenario 6 – OBSS Enterprise [2][3]
Fixed Location and Association
STA1
(5,-9.5)
STA2
(3.5,7.5)
STA4
(-4.5,0.5)
STA5
(-1.5,6)
STA7
(-9,-5)
STA8
(-8.5,8.5)
STA10
(-3,0.5)
STA11
(-0.5,8)
STA13
(-4,-4)
STA14
(7.5,-1)
STA16
(8,-6)
STA17
(0,-7.5)
STA19
(-2.5,-4.5)
STA20
(0.5,-2)
STA22
(0,-4.5)
STA23
(-1.5,7)
STA25
(3.5,-5)
STA26
(9,9.5)
STA28
(-8,-5.5)
STA29
(1.5,3.5)
AP A
(0,0)
AP B
(40,20)
AP C
(-40,-20)
STA3
(7.5+xb, ‑9.5+yb)
STA9
(7+xb, -7.5+yb)
STA15
(3+xb, -0.5+yb)
STA21
(-6.5+xb, -3+yb)
STA27
(‑6+xb, 2.5+yb)
STA6
(-5.5+xc,4.5+yc)
STA12
(7+xc,7+yc)
STA18
(10+xc,0.5+yc)
STA24
(3+xc,2.5+yc)
STA30
(9.5+xc,3.5+yc)
Suhwook Kim, LG Electronics

7. Traffic Flow Model [2][3]
November 2014
Traffic Flow Model [2][3]
DL/UL traffic assigned for each STA
STA DL UL
STA1 y
STA23 n
STA2
STA25
STA4
STA26
STA5
STA28
STA7
STA29
STA8
STA3
STA10
STA9
STA11
STA15
STA13
STA21
STA14
STA27
STA16
STA6
STA17
STA12
STA19
STA18
STA20
STA24
STA22
STA30
Suhwook Kim, LG Electronics

8. One BSS Test Result BSS B (STAs 3, 9, 15, 21, 27)
November 2014
One BSS Test Result
BSS B (STAs 3, 9, 15, 21, 27)
UL only & DL only, UDP CBR with rate 10^8bps
Total Tput
UL: Mbps
DL: Mbps
Suhwook Kim, LG Electronics

9. Observations DL throughput shows uniform distribution
November 2014
Observations
DL throughput shows uniform distribution
AP power is enough for fully supporting MCS 7
UL throughput is determined by distance from AP
UL total throughput shows 13.8% of performance degradation over DL total throughput because of collisions and lower TX power
Suhwook Kim, LG Electronics

10. Calibration with 1177r2 DL result is similar with 1177r2
November 2014
Calibration with 1177r2
DL result is similar with 1177r2
Total Tput: Mbps (1392r0) and Mbps (1177r2)
However UL results aren’t matched
Total Tput: Mbps (1392r0) and Mbps (1177r2)
Reason of mismatch in UL throughput may be difference of collision handling method
First step of Box-5 calibration will be aligning collision handling method in 1 BSS UL test case than any other cases
Suhwook Kim, LG Electronics

11. Used collision handling model
November 2014
Used collision handling model
CCA/receiving procedure at receiver side
If Rx power over T1 > Rx sensitivity, the STA switches to RX mode
Once switching to RX mode, the STA cannot receive other frame until end of current receiving frame
Calculate SINRs over T1 and T2, decide whether preamble field is success or not
If preamble is success, reception of each subframe can be decided by SINR over each subframe’s duration
If preamble is failed, all subframe is failed
Suhwook Kim, LG Electronics

12. Three BSS Test UL only November 2014 BSS C Total Tput: 115.47 Mbps
BSS B
Total Tput:
99.29 Mbps
BSS A
Total Tput:
61.88 Mbps
Suhwook Kim, LG Electronics

13. Three BSS Test DL only November 2014 BSS B Total Tput: 117.24 Mbps
BSS C
Total Tput:
Mbps
DL only
BSS A
Total Tput:
75.22 Mbps
Suhwook Kim, LG Electronics

14. November 2014
Observations
BSS A shows the lowest performance both UL and DL because of
interference from BSS B and C
larger number of STAs
DL performance of each BSS has uniform distribution
UL throughput is still
determined by distance from AP
Areal performance is
improved in 3 OBSSs
by 20~27% over than 1 BSS
BSS A
BSS C
BSS B
Suhwook Kim, LG Electronics

15. Calibration with 1177r2 Total Tput result
November 2014
Calibration with 1177r2
Total Tput result
In UL only case, performance ratio of BSS A, B and C is similar in 1392r0 and 1177r2
However, in DL only case, BSS A is more suffered from interference in 1177r2 result
1392r0
1177r2
UL only
BSS A
61.88 Mbps
85.34 Mbps
BSS B
99.29 Mbps
Mbps
BSS C
Mbps
Mbps
DL only
75.22 Mbps
33.29 Mbps
Mbps
Mbps
Mbps
Mbps
Suhwook Kim, LG Electronics

16. Three BSS Test Mixed UL & DL
November 2014
Three BSS Test
Mixed UL & DL
BSS A: Total Tput Mbps (DL Mbps, UL Mbps)
Suhwook Kim, LG Electronics

17. November 2014
Three BSS Test
UL & DL
BSS B: Total Tput Mbps (DL Mbps, UL Mbps)
BSS C: Total Tput Mbps (DL Mbps, UL Mbps)
Suhwook Kim, LG Electronics

18. Observations UL throughput shows similar pattern with UL only case
November 2014
Observations
UL throughput shows similar pattern with UL only case
DL throughput show similar patter with DL only case except BSS A
100 seconds are not enough to converge because of large number of stations in mixed DL and UL traffic
BSS B and C have more larger performance than DL or UL only case
However, performance of BSS A is degraded by stronger interference from BSS B and C
Suhwook Kim, LG Electronics

19. November 2014
Conclusion
In this submission, we provided simulation results for Box 5 calibration
Based on simulation results, we suggest the first step for Box 5 calibration is aligning collision model
Box 3 (MAC calibration) also handles collision model, so we have to align with Box 3 too
Suhwook Kim, LG Electronics

20. Reference [1] 11-14/0571r5 Evaluation Methodology
November 2014
Reference
[1] 11-14/0571r5 Evaluation Methodology
[2] 11-14/1177r2 Box5 Calibration Discussion
[3] 11-09/0451r16 TGac Functional Requirements and Evaluation Methodology
Suhwook Kim, LG Electronics