This document proposes adding an "effective radio resource utilization index" (ERUI) to the performance metrics in IEEE 802.16j-06/013. ERUI is defined as the radio resources used to transmit user data normalized by the resources used for 64-QAM 3/4 transmission. It provides a metric to evaluate the performance of path selection schemes in multi-hop relay (MMR) networks. The document defines how to calculate the ERUI for individual links and end-to-end paths in MMR networks. It also introduces reference MMR cell capacity as a benchmark to compare the effective capacity achieved by different path selection schemes. Examples are provided to illustrate how ERUI can be used to compare the performance of direct

1. Effective Radio Resource Utilization Index for MMR Performance Metric
IEEE 802.16 Presentation Submission Template (Rev. 8.3)
Document Number:
IEEE C802.16j-06/090
Date Submitted: 2006-xx-xx
Source:
Kanchei (Ken) Loa, Yung-Ting Lee,
Yi-Hsueh Tsai,
Institute for Information Industry
8F., No. 218, Sec. 2, Dunhua S. Rd.,
Taipei City, Taiwan.
Voice:
Fax:
E-mail:
886-2-2739-9616
886-2-2378-2328
loa@nmi.iii.org.tw
Venue:
IEEE 802.16 Session #45, Mont Tremblant, Canada
Base Document:
None.
Purpose:
This contribution proposes to add “effective radio resource utilization index” to Performance Metric in IEEE 802.16j-06/013.
Notice:
This document has been prepared to assist IEEE 802.16. It is offered as a basis for discussion and is not binding on the contributing individual(s) or organization(s). The material in this
document is subject to change in form and content after further study. The contributor(s) reserve(s) the right to add, amend or withdraw material contained herein.
Release:
The contributor grants a free, irrevocable license to the IEEE to incorporate material contained in this contribution, and any modifications thereof, in the creation of an IEEE Standards
publication; to copyright in the IEEE’s name any IEEE Standards publication even though it may include portions of this contribution; and at the IEEE’s sole discretion to permit others to
reproduce in whole or in part the resulting IEEE Standards publication. The contributor also acknowledges and accepts that this contribution may be made public by IEEE 802.16.
IEEE 802.16 Patent Policy:
The contributor is familiar with the IEEE 802.16 Patent Policy and Procedures <http://ieee802.org/16/ipr/patents/policy.html>, including the statement "IEEE standards may include the
known use of patent(s), including patent applications, provided the IEEE receives assurance from the patent holder or applicant with respect to patents essential for compliance with both
mandatory and optional portions of the standard." Early disclosure to the Working Group of patent information that might be relevant to the standard is essential to reduce the possibility
for delays in the development process and increase the likelihood that the draft publication will be approved for publication. Please notify the Chair <mailto:chair@wirelessman.org> as
early as possible, in written or electronic form, if patented technology (or technology under patent application) might be incorporated into a draft standard being developed within the IEEE
802.16 Working Group. The Chair will disclose this notification via the IEEE 802.16 web site <http://ieee802.org/16/ipr/patents/notices>.
1

2. Introduction
This contribution proposes to add “effective radio
resource utilization index” to Performance Metric
in IEEE 802.16j-06/013
“Effective system spectral efficiency” is defined as
a system-wise performance parameter, however, it
lacks of the granularity of multi-hop path and
cannot be used to evaluate path selection schemes.
The purpose of “effective radio resource utilization
index” is to facilitate the evaluation of path
selection schemes for MMR networks.
2

3. Definition of Effective Radio
Resource Utilization Index (ERUI)
Effective radio resource utilization index
(ERUI) is defined as the radio resource
used to transmit the user data normalized
by the radio resource used to transmit the
same data using 64-QAM CC ¾ with
repetition 1. The radio resource is limited
to OFDMA slot.
3

4. Table 1 ERUI of DL Burst Profiles
Type
00
01
02
03
04
10
11
12
13
20
21
22
23
Mod.
QPSK
16-QAM
64-QAM
Burst Profile
Coding
CC/BTC/CTC ½
CC/BTC/CTC ¾
CC/CTC ½
*1 BTC ½
*2 CC/CTC ¾
BTC ¾
CC/CTC 2/3
BTC ¾
CC/CTC ¾
CTC 5/6
*1: also 64-QAM BTC 1/3
Rep.
6
4
2
1
1
1
1
bytes/slot
ERUI
1
1.5
3
6
9
12
16
18
20
24
25
27
30
27.0000
18.0000
9.0000
4.5000
3.0000
2.2500
1.6875
1.5000
1.3500
1.1250
1.0800
1.0000
0.9000
*2: also 64-QAM CC/CTC ½
4

5. The i-th MS ERUI
h 1
i
MS
r
 w r  w r
nj
n j 1
n1 n1
0 0
j 2
nj
nj
n j 1 n j 1
w r
i
i
nh1 nh1
where w is a weighting factor due to the radio resource
reuse, multicast/broadcast, or spatial diversity.
Four examples are given in Figure 1:
Figure 1a: all weighting factors are 1
Figure 1b: radio resource reuse scenario
Figure 1c: multicast/broadcast scenario
Figure 1d: spatial diversity scenario
5

6. Figure 1a All Weighting Factors are 1
ERUI  r0n1
BS0
RSn1
ERUI  rnn2
1
RSn2
i
MS ERUI  rMS  r0n1  rnn2  rni2
1
ERUI  rni2
MSi
6

7. Figure 1b Radio Resource Reuse Scenario
ERUI  r01
ERUI  r14
RS1
ERUI  r03
BS0
ERUI  r
2
0
RS2
MS4
ERUI  r25
4
rMS  r01  1 r14
2
RS3
ERUI  r36
MS6
6
rMS  r03  1 r36
2
MS5
7

8. Figure 1c Multicast/Broadcast Scenario
ERUI  r01  ra
ERUI  r13  rb
MS3
RS1
ERUI  r02  ra
BS0
ERUI  r15  rb
ERUI  r14  rb
MS4
3
4
5
rMS  rMS  rMS  1 ra  1 rb
2
3
RS2
MS5
ERUI  r26
MS6
6
rMS  1 ra  r26
2
8

9. Figure 1d Spatial Diversity Scenario
ERUI  r02
BS0
ERUI  r01
RS2
RS1
ERUI  r23
RS3
ERUI  r14  ra
MS4

 
ERUI  r14  ra

4
rMS  r01  1 r14  r02  r23  1 r34  r01  r02  r23  ra
2
2
9

10. The MMR-cell ERUI
In order to compare the performance of the path
selection for the MMR-cell, the effective MMR-cell
capacity is defined as




i
i
i
i
C MMR  cell   rMS in downstream  TDL   rMS in upstream  TUL
i
i
i
i
where TDL and TUL denote the transmitting data
amounts at i-th MS in unit of 64QAM CC ¾ with
repetition 1 for DL and UL, respectively.
10

11. Reference MMR-cell Capacity
Moreover, reference MMR-cell capacity is defined as
a reference of radio resource utilization (i.e. OFDMA
slots) for data transmission when 64QAM CC ¾ with
repetition 1 is used for all relay paths and access links.
The value of the effective MMR-cell capacity shall be
less than the reference MMR-cell capacity.
The optimized path selection for all MSs via relay
paths in an MMR cell is to maximize the effective
MMR-cell capacity.
11

12. Annex
Examples of Comparison between
Direct Path and Indirect Path

13. Figure 2a Indirect Path is Better
BS
QPSK CC ½
 ERUI Type = 03
 ERUI = 4.5
BS
64-QAM CC ½
 ERUI Type = 12
 ERUI = 1.5
RS
16-QAM CC ¾
 ERUI Type = 12
 ERUI = 1.5
3 < 4.5
MS
Total = 1.5 + 1.5 = 3
MS
* all weighting factors are set as 1
13

14. Figure 2b Both are The Same
BS
QPSK CC ¾
 ERUI Type = 04
 ERUI = 3
MS
RS
16-QAM CC ¾
 ERUI Type = 12
 ERUI = 1.5
3=3
BS
64-QAM CC ½
 ERUI Type = 12
 ERUI = 1.5
Total = 1.5 + 1.5 = 3
Both are the same (3 = 3)
* all weighting factors are set as 1
MS
14

15. Figure 2c Direct Path is Better
BS
16-QAM CC ¾
 ERUI Type = 10
 ERUI = 2.25
BS
64-QAM CC ½
 ERUI Type = 12
 ERUI = 1.5
RS
16-QAM CC ¾
 ERUI Type = 12
 ERUI = 1.5
3 < 4.5
MS
Total = 1.5 + 1.5 = 3
MS
* all weighting factors are set as 1
15

16. Figure 3a Indirect Path is Better
BS
QPSK CC ¾
 ERUI Type = 04
 ERUI = 3
BS
64-QAM CC ¾
 ERUI Type = 22
 ERUI = 1
RS
16-QAM CC ¾
 ERUI Type = 12
 ERUI = 1.5
1.5 < 3
MS
Total = 1 + (1/3) * 1.5 = 1.5
MS
* The weighting factors of RS-MS link are set as 1/3
16

17. Figure 3b Both are The Same
BS
16-QAM CC ¾
 ERUI Type = 12
 ERUI = 1.5
BS
64-QAM CC ¾
 ERUI Type = 22
 ERUI = 1
RS
16-QAM CC ¾
 ERUI Type = 12
 ERUI = 1.5
1.5 = 1.5
MS
Total = 1 + (1/3) * 1.5 = 1.5
MS
* The weighting factors of RS-MS link are set as 1/3
17

18. Figure 3c Direct Path is Better
BS
64-QAM CC 2/3
 ERUI Type = 20
 ERUI = 1.125
BS
64-QAM CC ¾
 ERUI Type = 22
 ERUI = 1
RS
Total = 1 + (1/3) * 1.5 = 1.5
16-QAM CC ¾
 ERUI Type = 12
 ERUI = 1.5
1.5 > 1.125
MS
MS
* The weighting factors of RS-MS link are set as 1/3
18

19. EURI of Indirect Path (2-hop Scenario)
Burst Profile for RS-MS
Type
00
01
02
03
04
10
11
12
13
20
21
22
23
Burst Profile for BS-RS
23
22
21
20
13
12
11
10
04
03
27.9000
28.0000
28.0800
28.1250
28.3500
28.5000
28.6875
29.2500
30.0000
31.5000
18.9000
19.0000
19.0800
19.1250
19.3500
19.5000
19.6875
20.2500
21.0000
22.5000
9.9000
10.0000
10.0800
10.1250
10.3500
10.5000
10.6875
11.2500
12.0000
13.5000
5.4000
5.5000
5.5800
5.6250
5.8500
6.0000
6.1875
6.7500
7.5000
9.0000
3.9000
4.0000
4.0800
4.1250
4.3500
4.5000
4.6875
5.2500
6.0000
7.5000
3.1500
3.2500
3.3300
3.3750
3.6000
3.7500
3.9375
4.5000
5.2500
6.7500
2.5875
2.6875
2.7675
2.8125
3.0375
3.1875
3.3750
3.9375
4.6875
6.1875
2.4000
2.5000
2.5800
2.6250
2.8500
3.0000
3.1875
3.7500
4.5000
6.0000
2.2500
2.3500
2.4300
2.4750
2.7000
2.8500
3.0375
3.6000
4.3500
5.8500
2.0250
2.1250
2.2050
2.2500
2.4750
2.6250
2.8125
3.3750
4.1250
5.6250
1.9800
2.0800
2.1600
2.2050
2.4300
2.5800
2.7675
3.3300
4.0800
5.5800
1.9000
2.0000
2.0800
2.1250
2.3500
2.5000
2.6875
3.2500
4.0000
5.5000
1.8000
1.9000
1.9800
2.0250
2.2500
2.4000
2.5875
3.1500
3.9000
5.4000
19
* the weighting factors are set as 1

20. Reference
1) IEEE 802.16j-06/013, “Multi-hop Relay System
Evaluation Methodology (Channel Model and
Performance Metric)”, September 2006.
20