1. Evaluation and Proposed Text on UL Tile Permutation
Document Number:
IEEE C80216m-09_0628r3
Date Submitted:
Source:
HanGyu Cho, Seunghyun Kang, Jong Young Han, Sunam Kim,
Jin Sam Kwak LG Electronics
Yanfeng Guan ZTE Corporation
Shaohua Li, Xin Qi Nokia Siemens Networks
Yu-Tao Hsieh ITRI
Luciano Sarperi Fujitsu
Venue:
“802.16m AWD”: IEEE m-09/0012. ”Call for Contribution on Project m Amendment
Working Document (AWD) Content” Target topic: Call for Comments on Amendment Working
Document
Purpose:
To provide proposed text on DL subcarrier permutation to be approved by TGm and adopted in the
Amendment Working Document
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2. Motivation
In the current IEEE m Amendment Working Document (IEEE m-09/0010), the UL tile permutation formula in the section is TBD
So far, there have been many tile permutation formulas proposed by each company
This contribution reviews those rules and suggests a UL tile permutation formula based on simulation results.

3. Evaluation Criteria for Tile Permutation
Link level simulation
To show the diversity gain for distributed LRU
Hit ratio
To check the interference averaging effect of distributed LRU

4. Tile Permutation Formulas Considered
LGE’s proposed formula
where
where
where

5. Tile Permutation Formulas Considered
Intel (IEEE m-09/0265)
where PermSeq(L;i) is the i-th entry of the permutation sequence of length
L as defined by the following equation
where

6. Tile Permutation Formulas Considered
Samsung (IEEE m-09/0206r3 )
where PermSeq is the sequence of length LDRU,FPi and is determined by SEED = {(IDcell+1024*t)* } mod 220. The IDcell is the cell identification. The specific permutation sequence generation algorithm with 20-bit SEED (Sn-20, Sn-19, … , Sn-1) and a permutation size of M is defined as below (refer to IEEE m-09/0206r3 ).
where or

7. Subcarrier Permutation Formulas Considered
Samsung (updated) (C802.16m-09/0582)
PermSeq is the sequence of length LDRU, FPi and is determined by SEED = {IDcell*1367} mod 210 and the permutation sequence generation algorithm specified in C80216m-09_0582
where

8. Tile Permutation Formulas Considered
NSN (IEEE m-09/0260r2 )

9. Simulation Environment: LLS (1/2)
BW=10MHz (NPRU=48) – IEEE m-09/0251
Scenario1 (Mixed Reuse 1&3 – equal size)
Scenario 3 (Reuse 1)
Freq. Partition
# of subbands
(KSB,FP,i)
# of minibands
(KMB,FPi)
# of PRUs in FPi
FP1 2 4 12
FP2
FP3
FP4
Freq. Partition
# of subbands
(KSB,FP,i)
# of minibands
(KMB,FPi)
# of PRUs in FPi
FP1 6 24 48
FP2
FP3
FP4
Scenario 2 (Mixed Reuse 1&3 – unequal size)
Scenario 4 (Reuse 3)
Freq. Partition
# of subbands
(KSB,FP,i)
# of minibands
(KMB,FPi)
# of PRUs in FPi
FP1 4 8 24
FP2
FP3
FP4
Freq. Partition
# of subbands
(KSB,FP,i)
# of minibands
(KMB,FPi)
# of PRUs in FPi
FP1
FP2 2 8 16
FP3
FP4

10. Simulation Environment: LLS (2/2)
Antenna configuration
2x2 SFBC
MMSE MIMO Receiver
Channel
Scenario : MAND_MIXED
Model : Veh A
Perfect channel estimation
QPSK, ½ code rate
Averaged over cell ID 0 ~ 47

11. Simulation Results: LLS
Scenario 1

12. Simulation Results: LLS
Scenario 2

13. Simulation Results: LLS
Scenario 3

14. Simulation Results: LLS
Scenario 4

15. Conclusion on LLS results
We evaluated UL tile permutations with varying scenarios.
In terms of diversity gain, LGE, Intel, SS have the same performance in all cases

16. Simulation Environment: Hit ratioBW
10MHz
#Cell ID
512
Distributed LRU
3 6by6 tiles
NDRU
varying
For choose(512,2)= cell pairs,
For each cell pair, there are NDRU * NDRU sub-channel pairs,
Hit Number: the number of same tiles for each sub-channel pair
Average Hit Number: hit statistic over cell pairs
% of total hits: (Average Hit Number) / (NDRU * NDRU) * 100%

17. Simulation Results: Hit ratio
#. of DRUs
# of Hits 1 2 3 4
LGE
43.70 %
40.52
12.88
2.91
Intel
49.95
31.31
12.52
6.21
Samsung
47.16
36.15
11.20
5.48
Samsung (updated)
48.87
33.27
11.84
6.02 8
66.91
28.95
3.88
0.27
71.84
21.14
4.70
2.32
69.23
25.02
4.76
0.99
68.39
26.43
4.47
0.71 12
76.92
21.27
1.71
0.10
80.19
15.42
3.59
0.80
77.49
20.21
2.11
0.19
77.98
19.35
2.35
0.31 24
87.95
11.61
0.41
0.02
88.66
10.39
0.74
0.21
88.19
11.16
0.60
0.05
88.53
10.58
0.76
0.13 48
93.87
0.008
94.15
5.49
0.30
0.050
93.96
5.85
0.18
0.016
94.06
5.66
0.23
0.04
Best cases were bolded for larger hits

18. Simulation Results: modified LLS
Two cells: Home cell and Interfering cell
Scenario 1 (4DRUs per FP)
25% partial loading
Cell IDs averaged over 0 ~ 47

19. Simulation Environment: Hit ratioBW
10MHz
#Cell ID
512
Distributed LRU
3 6by6 tiles
NDRU
varying
For choose(512,2)= cell pairs,
For each cell pair, select contiguous N sub-channels from sub-channel number 0 for each cell
Hit Number: the number of same tiles for each sub-channel pair (Hit number range is [0, 3N])
Average Hit Number: hit statistic over cell pairs
% of total hits: (Average Hit Number) * 100%
This hit ratio comparison is more realistic to see the effect of hit ratio on SLS performance

20. Simulation Environment: Hit ratio
LGE’s UL tile permutation formula considered
SS’s UL tile permutation formula considered
For the purpose of comparison we use the same permutation sequence (SS’s sequence in C802.16m-09/0582)
where
where

21. Simulation Results: Hit ratio
SS's equation
LGE's equation
#Hit
% of Total Hits
Num Hit
1553
1480 1
7790
7267 2
17840
17655 3
26483
26793 4
28373
28779 5
22670
22948 6
14224
14477 7
7232
7191 8
3042
2906 9
1049
0.7415
970 10
351
260 11
121 66 12 52 15 13 18 14 16 17 19 20 21 22 23 24
# DRU = 48
N=8 (1/6 loading)

22. Simulation Results: Hit ratio
# DRU = 24
N=4 (1/6 loading)
SS's equation
LGE's equation
#Hit
% of Total Hits
Num Hit
11827
12565 1
29837
34533 2
36882
40955 3
28419
26835 4
15413
11585 5
5893
3388 6
1800
763 7
485
141 8
136 37 9 78 10 22 11 12

23. Simulation Results: Hit ratio
# DRU = 4
N=1 (1/4 loading)
SS's equation
LGE's equation
#Hit
% of Total Hits
Num Hit
57344
57677 1
39936
37891 2
10240
27647 3
23296
7601

24. Conclusion on Hit ratio results
In terms of hitting ratio, LGE has the best performance showing the smallest ‘larger hit ratios (2 or 3 hit cases)’ in most scenarios

25. Conclusions Different proposals show different conclusions
In this contribution, LGE is the best in terms of hit ratio and modified LLS
In C80216m-09_0551 (ITRI), ITRI and LGE is the best in terms of hit ratio
In C80216m-09_0582r1 (Samsung), Samsung is the best in terms of SLS only when random_Permbase is assumed, but, the reason is unclear.
Comparison with more proposals are necessary assuming the agreed decision criterion and simulation environment
This contribution only compares LGE, Intel, SS in terms of modified LLS
C80216m-09_0582r1 (Samsung) only compares SS and LGE,
It is necessary to provide comparison with ITRI and NSN and some other proposals if any for fair comparison
It is better to adopt the UL tile permutation formula in the next meeting based on the results enough to make a final decision

26. Proposed Text
Please leave the equation (196) of page 42 of Amendment Working Document IEEE m-09/0010 as it is