Design of Downlink Broadcast Control Channel for 802.16m
Document Number: S80216m-08/140
Date Submitted: 2008-03-14
Source:
Yih-Shen Chen, I-Kang Fu, Kelvin Chou,
Dora Chen and Paul Cheng
Voice: +886-3-5670766
E-mail: yihshen.chen@mediatek.com, IK.Fu@mediatek.com,
Paul.Cheng@mediatek.com
MediaTek Inc.
Venue:
IEEE session #54, Orlando, FL.
Base Contribution:
C80216m-08/140.
Purpose:
For discussion on the downlink control channel issues and adoption on proposed text to SDD by TGm
Notice:
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.
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.
Patent Policy:
The contributor is familiar with the IEEE-SA Patent Policy and Procedures:
<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 >.
Motivation
• The acquisition of DCD/UCD are required for
initial network entry procedure
– The current DCD/UCD broadcast cycle is long and
inefficient
• The longest duration could be 10s
• The whole DCD/UCD table should be re-broadcasted if any
parameter is updated
• In 802.16m SRD, the maximal state transition
latency from idle mode to active mode is 100ms
– A new method for broadcasting system information is
required
2
Introduction
• The content of DCD/UCD:
– Network entry related: BSID, frame duration, ranging code
allocation and etc
– Others: handover parameters, measurement parameters and etc
• The characteristics of the content of DCD/UCD:
– static/semi-static: BSID, frame duration, HARQ parameters,
handover parameters and etc
– dynamic: UL loading, contention backoff number and etc
• An efficient broadcast control channel (BCH) is proposed
to broadcast and update the parameters efficiently
– Basic DCD/UCD and sub-DCD/sub-UCD
– Additionally, scheduling information block (SIB) is employed to
announce the information updating in a broadcast cycle
3
Categorization of System Information in
DCD/UCD
• the system information is generally
categorized into a basic-DCD (basic-UCD)
and multiple of sub-DCDs (sub-UCDs)
– basic-DCD/basic-UCD: the necessary
information required for network entry
– sub-DCD/sub-UCD: a set of parameters for
other specific functions
4
Example of DCD/UCD Categorization
basic-DCD
system frame number
BW info.
frame Configuration, TTG/RTG
ranging
downlink burst profile
etc
sub-DCD1
static parameters for DL data transmission
sub-DCD2
dynamic parameters for DL data transmission
sub-DCD3
parameters for handover procedure
….
…
basic-UCD
uplink burst profile
permutation
ranging code
etc
sub-UCD1
static parameters of UL transmission
sub-UCD2
dynamic parameters of UL transmission
sub-UCD3
parameters for special subchannel configuration
sub-UCD4
parameters for measurement report
…
…
The detail categorization is FFS.
5
Downlink Broadcast Control Channel
broadcast cycle
…
superframe j
superframe N
SuperMAP
SIB
…
sub-DCD/sub-UCD i
sub-DCD/sub-UCD j
basic-DCD/basic-UCD
sub-DCD/sub-UCD
sub-DCD/sub-UCD N
• The DCD/UCD are broadcasted via superMAP at the
first frame of a superframe
• A SIB announce the information scheduling for a
broadcast cycle
– The basic-DCD/basic-UCD appear every 20ms
– The sub-DCDs/sub-UCDs appear dynamically
6
Downlink Broadcast Control Channel
• SIB appears in the superMAP of the first
superframe of a broadcast cycle
– MAC management message may also be
included
• Benefits of SIB:
– MS can expect when a certain system information
can be received
– MS may choose to skip some unwanted or
duplicate system information
Sub-DCD1/
subUCD-1
Sub-DCD2/
subUCD-2
Sub-DCD3/
subUCD-3
Sub-DCD1/
subUCD-1
Sub-DCD4/
subUCD-4
Sub-DCD2/ MOB_NBR- Sub-DCD4/
subUCD-2
ADV
subUCD-4
Sub-DCD2/
subUCD-2
N/A
7
Text Proposal
• Add the description of downlink broadcast control channel to TGm SDD [5]
……
10 Media Access Control Sub-Layer
10.x Downlink broadcast control channel
•
Add the two figures in the section 10.x
broadcast cycle
…
superframe N
superframe j
SuperMAP
SIB
basic-DCD/basic-UCD
sub-DCD/sub-UCD i
sub-DCD/sub-UCD j
…
sub-DCD/sub-UCD
sub-DCD/sub-UCD N
Figure y: downlink broadcast control channel
Sub-DCD1/
subUCD-1
Sub-DCD2/
subUCD-2
Sub-DCD3/
subUCD-3
Sub-DCD1/
subUCD-1
Sub-DCD4/
subUCD-4
Sub-DCD2/ MOB_NBR- Sub-DCD4/
subUCD-2
ADV
subUCD-4
Figure z: An example of SIB message
Sub-DCD2/
subUCD-2
N/A
8