IEEE 802.16m-08/1452
Project
IEEE 802.16 Broadband Wireless Access Working Group <http://ieee802.org/16>
Title
Proposed Baseline Text of Uplink Physical Structure Section for the IEEE 802.16m
Amendment
Date
Submitted
2008-11-03
Source(s)
Jeongho Park, Junsung Lim, Hokyu Choi,
Heewon Kang
Samsung Electronics Co., Ltd.
416 Maetan-3, Suwon, 442-600, Korea
Re:
“16m amendment text”
Voice:
E-mail:
+82-31-279-7528
jeongho.jh.park@samsung.com
IEEE 802.16m-08/042, “Call for Contributions on Project 802.16m Draft Amendment Content”.
Target topic: “Uplink Physical Structure (data plane only)”.
Abstract
The contribution proposes the text of uplink physical structure section (11.6) to be included in the
802.16m amendment.
Purpose
To be discussed and adopted by TGm for the 802.16m amendment.
Notice
Release
Patent
Policy
This document does not represent the agreed views of the IEEE 802.16 Working Group or any of its subgroups. It
represents only the views of the participants listed in the “Source(s)” field above. It is offered as a basis for discussion.
It is not binding on the contributor(s), who reserve(s) the right to add, amend or withdraw material contained herein.
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
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acknowledges and accepts that this contribution may be made public by IEEE 802.16.
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<http://standards.ieee.org/guides/bylaws/sect6-7.html#6> and
<http://standards.ieee.org/guides/opman/sect6.html#6.3>.
Further information is located at <http://standards.ieee.org/board/pat/pat-material.html> and
<http://standards.ieee.org/board/pat>.
Proposed Baseline Text of Uplink Physical Structure Section
for the IEEE 802.16m Amendment
Jeongho Park, Junsung Lim, Hokyu Choi, Heewon Kang
Samsung Electronics Co., Ltd.
1. Introduction
The contribution proposes the text of uplink physical structure section for harmonization in order to be included
in the 802.16m amendment as baseline. The proposed text is developed so that it can be readily combined with
IEEE P802.16 Rev2/D7 [2], it is compliant to the 802.16m SRD [4] and the 802.16m SDD [3] , and it follows
the style and format guidelines in [5].
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IEEE 802.16m-08/1452
2. Modifications to the SDD [4] text
The text proposed in this contribution is based on subclauses 11.6 in the IEEE 802.16m SDD [3]. Most of part is
maintained as SDD text. The modifications to the SDD text are summarized below:

Terminologies for legacy equipment/operation used in [3][4] are changed as follows:
legacy MS or IEEE 802.16e MS to WirelessMAN-OFDMA MS,
legacy BS or IEEE 802.16e BS to WirelessMAN-OFDMA BS,
legacy zone or IEEE 802.16e zone to WirelessMAN-OFDMA zone

Subchannelization procedure in Section 15.3.6.2 is maintained according to [3], while some
terminologies in Section 15.3.6.2 are cleaned up using definitions in ‘Section 3 Definitions’ of the
proposed text.

Control channel structure is left out.

Basic symbol structure and subchannelization for FDM Support of WirelessMAN-OFDMA UL PUSC
zone are added.
3. References
[1] IEEE 802.16m-08/1339, “Proposed Text of Frame Structure Section for the IEEE 802.16m Amendmen”
[2] IEEE P802.16 Rev2/D7, “Draft IEEE Standard for Local and Metropolitan Area Networks: Air Interface
for Broadband Wireless Access,” Oct. 2008.
[3] IEEE 802.16m-08/003r5, “The Draft IEEE 802.16m System Description Document”
[4] IEEE 802.16m-07/002r6, “802.16m System Requirements”
[5] IEEE 802.16m-08/043, “Style guide for writing the IEEE 802.16m amendment”
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4. Text proposal for inclusion in the 802.16m amendment
-------------------------------
Text Start
---------------------------------------------------
3. Definitions
Insert the following at the end of section 3.1:
xx. PRU : 18x6 (consecutive subcarriers) which include the resource unit before the outer permutation.
xx. DRU: This has still 18x6 PRU structure, which is going to be permuted by DL/UL inner permutation
xx. CRU: This has still 18x6 RU structure, which will pass-through inner permutation (i.e. is not going to be
inner permuted). CRU has two types - subband-based CRU and PRU-based CRU, depending on system
parameters.
xx. LRU : Basic logical unit for distributed and localized resource allocations.
xx. Distributed-LRU: the LRU which is obtained from distributed allocation after inner permutation
xx. Localized-LRU: the LRU obtained from localized allocation via. pass-through inner permutation
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IEEE 802.16m-08/1452
Insert a new section 15:
15. Advanced Air Interface
15.3. Physical layer
15.3.6.
Uplink physical structure
Each uplink subframe is divided into a number of frequency partitions, where each partition consists of a set
of physical resource units across the total number of OFDMA symbols available in the subframe. Each
frequency partition can include contiguous (localized) and/or non-contiguous (distributed) physical resource
units. Each frequency partition can be used for different purposes such as fractional frequency reuse (FFR).
Figure 1 illustrates the uplink physical structure in the example of two FFR groups with FFR group 2
including both localized and distributed resource allocations.
Figure 1 - Example of uplink physical structure
15.3.6.1.
Physical and Logical Resource Unit
A physical resource unit (PRU) is the basic physical unit for resource allocation that comprises Psc
consecutive subcarriers by Nsym consecutive OFDMA symbols. Psc is 18 subcarriers and Nsym is the number of
OFDMA symbols depending on the subframe type. A logical resource unit (LRU) is the basic logical unit for
distributed and localized resource allocations. The size of LRU for data transmission is Psc* Nsym. Each LRU
for data transmission can have different number of tones which are available for data allocation according to
the number of pilots.
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IEEE 802.16m-08/1452
15.3.6.1.1.
Distributed Logical Resource Unit
The distributed logical resource unit (distributed-LRU) is used to achieve frequency diversity gain. The
distributed-LRU contains a group of subcarriers which are spread across the distributed resource group within
a frequency partition. The size of the distributed-LRU equals the size of PRU, i.e., Psc subcarriers by Nsym
OFDMA symbols. The minimum unit for forming the distributed-LRU is a tile. The size of a tile is 6 by Nsym.
15.3.6.1.2.
Localized Logical Resource Unit
The localized logical resource unit (localized-LRU) is used to achieve frequency-selective scheduling gain. A
localized-LRU contains a group of subcarriers which are contiguous across the localized resource group. The
size of a localized-LRU equals the size PRU, i.e., Psc subcarriers by Nsym OFDMA symbols.
15.3.6.2.
Subchannelization and Resource mapping
15.3.6.2.1.
Basic Symbol Structure
The subcarriers of an OFDMA symbol are partitioned into N g,left left guard subcarriers, Ng,right right guard
subcarriers, and Nused used subcarriers. The DC subcarrier is not loaded. The Nused subcarriers are divided into
PRUs. Each PRU contains pilot and data subcarriers. The number of used pilot and data subcarriers depends
on MIMO mode, rank and number of multiplexed MS and the type of resource allocation, i.e., distributed or
localized resource allocations as well as the type of the subframe, i.e., type-1 or type-2.
15.3.6.2.2.
Uplink Subcarrier to Resource Unit Mapping
The main features of resource mapping include:
1.
Support of localized-LRU and distributed-LRU in an FDM manner.
2. Distributed-LRUs comprise multiple tiles which are spread across the distributed resource group within
a frequency partition to get diversity gain.
3.
FFR can be applied in uplink physical structure.
Based on the main design concepts above, the UL subcarriers to resource unit mapping process is defined as
follows and illustrated in Figure 2:
1.
First-level or outer permutation is applied to the PRUs in the units of N1 and N2 PRUs, where N1=4 and
N2 =1 or 2 depending on system bandwidth. Direct mapping of outer permutation can be supported only
for CRU.
2.
Distributing the reordered PRUs into frequency partitions..
3. The frequency partition is divided into CRU and/or DRU for each resource group. Sector specific
permutation can be supported and direct mapping of the resources can be supported for localized resources.
The sizes of the distributed/localized resources are flexibly configured per sector. Adjacent sectors do not
need to have same configuration of localized and distributed resources.
4. The localized and distributed groups resources are further mapped into LRUs by direct mapping of
CRU and by inner permutation on DRUs, as shown in Figure 2.
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IEEE 802.16m-08/1452
Freq. Part1
Permutation
CRU
Permutation
(Outer)
Permutation
of PRU to
Freq.
Partitions
Distribute PRUs
to CRU/DRU
Freq. Part2
Physical frequency (PRUs)
Distribute PRU to Freq
Partitions
CRU
DRU
Perm.
Freq.
Part3
DRU
LRU (distributed and
localized)
tile
permutation
00
01
02
03
04
05
06
07
08
09
...
tile
permutation
CRU
Inter-cell (semi static)
Intra-cell (potentially dynamic)
Figure 2 – Illustration of the uplink subcarrier to resource unit mapping
15.3.6.2.3.
Subchannelization for Uplink Distributed Resource Unit
An inner permutation permutes PRUs in DRU within a frequency partition. The tile permutation defined for
the uplink distributed resource allocations spreads the tiles of the LDRU across the whole allocated
distributed resource allocations frequency band.
Two kinds of distributed resource allocation are used for UL distributed subchannelization, (1) regular
distributed allocation (2) UL transmit power optimized distributed allocation. The UL transmit power
optimized distributed resource is allocated first. The rest of the frequency resource is then allocated for
regular distributed allocation. A hopping/permutation sequence (TBD) is defined for the power optimized
allocation that spreads the hopping units across frequency. The second-level or inner permutation defined for
the UL regular distributed resource allocations spreads the tiles of the LDRU across the frequency band. The
granularity of the inner permutation is equal to the tile size for forming a LDRU according to section
15.3.6.1.1.
15.3.6.2.4.
Subchannelization for Uplink Contiguous Resource Unit
There is no permutation defined for the uplink contiguous resource unit. The PRUs in CRU are directly
mapped to localized-LRUs within each frequency partition.
15.3.6.3.
Pilot Structure
The transmission of pilot subcarriers in the uplink is necessary for enabling channel estimation,
measurements of SINR, frequency and time offset estimation, etc. Uplink pilot is dedicated to each user and
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IEEE 802.16m-08/1452
can be precoded or beamformed in the same way as the data subcarriers of the resource allocation. The pilot
structure is defined for up to 4 transmission streams.
Pilot structures for each tile structure used for distributed-LRU and for localized-LRU are shown in Figure 3
and Figure 4. Figure 3 shows the pilot structure for localized-LRU when the number of stream is one, two
and four. Note that the pilot patterns for UL localized-LRUs are same to the downlink case. Figure 4 is used
for distributed-LRUs when the number of stream is one and two.
6 symbols
1
18 contiguous subcarriers
1
1
2
1
1
1
2
1
1
2
1
1
2
1 3
2 4
2 4
1 3
3 1
4 2
4 2
3 1
1
2
1
2
Figure 3 – Pilot patterns for localized-LRUs in case of 1 Tx, 2 Tx and 4 Tx
6 symbols
6 contiguous
subcarriers
1
1
1
1
2
1
1
2
1
2
1
2
Figure 4 – Pilot patterns for distributed-LRUs in case of 1 Tx and 2 Tx
15.3.6.4.
WirelessMAN-OFDMA Systems Support
When frame structure is supporting the WirelessMAN-OFDMA MSs in PUSC zone by FDM manner as
defined in 15.3.3.4 [1], a new symbol structure and subchannelization defined in this section are used.
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IEEE 802.16m-08/1452
15.3.6.4.1.
Basic Symbol Structure for FDM based UL PUSC Zone Support
The subcarriers of an OFDMA are partitioned into N g,left left guard subcarriers, Ng,right right guard subcarriers,
and Nused used subcarriers. The DC subcarrier is not loaded. The Nused subcarriers are divided into multiple
PUSC tiles. Basic symbol structures for various bandwidths are shown in from Table 1 to Table 3.
Table 1 – 512 FFT OFDMA UL subcarrier allocations for DRU
Parameters
Number of DC subcarriers
Guard subcarrier: Ng,left, Ng,right
Value
1
52, 51
Number of total used subcarriers (Nused)
409
Comments
Subcarrier index 204
Number of all subcarriers used in
WirelessMAN-OFDMA PUSC zone
within a symbol, including DC carrier
Table 2 – 1024 FFT OFDMA UL subcarrier allocations for DRU
Parameters
Number of DC subcarriers
Guard subcarrier: Ng,left, Ng,right
Value
1
92, 91
Number of total used subcarriers (Nused)
841
Comments
Subcarrier index 420
Number of all subcarriers used in
WirelessMAN-OFDMA PUSC zone
within a symbol, including DC carrier
Table 3 – 2048 FFT FFT OFDMA UL subcarrier allocations for DRU
Parameters
Number of DC subcarriers
Guard subcarrier: Ng,left, Ng,right
Value
1
160, 159
Number of total used subcarriers (Nused)
1681
15.3.6.4.2.
Comments
Subcarrier index 840
Number of all subcarriers used in
WirelessMAN-OFDMA PUSC zone
within a symbol, including DC carrier
Resource Unit Structure for FDM based UL PUSC Zone Support
When supporting FDM based UL PUSC zone, a tile consists of 4 consecutive subcarriers and Nsym OFDMA
symbols depending on the subframe type. A tile structure and pilot pattern for 6 symbol-subframe is shown in
Figure 5.
4 contiguous
subcarriers
6 symbols
Figure 5 – Tile structure and pilot patterns for FDM based UL PUSC zone Support
(Pilot pattern is TBD)
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IEEE 802.16m-08/1452
15.3.6.4.3.
Subchannelization for FDM based UL PUSC Zone Support
When supporting FDM based UL PUSC zone, UL subchannelization is as follows:
1. For the WirelessMAN-OFDMA system bandwidth, all usable subcarriers are divided into PUSC tiles.
2. UL PUSC subchannelization is performed as described in section 8.4.6.2.2 [2].
3. Available subchannels for Advanced Air Interface MS shall be specified through subchannel bitmap
broadcasted by [DL broadcasting control message, TBD].
4. All PUSC tiles of specified subchannels from step 3 are extended in time domain from 3 OFDM symbols
to Nsym OFDM symbols, where Nsym is dependent of subframe type. These tiles are for distributed-LRUs.
5. Based on specified subchannels of step 3 with symbol extension tiles of step 4, distributed LRUs for
Advanced Air Interface are made up.
6. Repeat step 4 and step 5 for every subframe in uplink transmission.
Overall process of subcarrier to subchannel mapping is shown in Figure 6.
PUSC tile
0
Tile for LRU
206
208
209
3 symbols
4 subcarriers
207
62
PUSC10
PUSC33
LRU 0
61
PUSC34
LRU 1
63
64
65
...
PUSC
subchannelization
Distributed LRUs for
Advance Air Interface
60
PUSC9
207
4 subcarriers
.
.
.
.
.
.
Symbol
extension
...
PUSC1
3
Subchannels for
Advance Air Interface
840 subcarriers when BW=10MHz
2
Subchannels for
WirelessMAN
OFDMA system
PUSC0
1
LRU 24
208
209
Nsym
symbols
Figure 6 –Example of subchannelization for FDM based UL PUSC zone support (when system bandwidth is 10MHz)
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Text End
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