Document Number: C802.16m-08/564

1
Mobility Management with Multi-Carrier Support
for IEEE 802.16m

• Document Number C802.16m-08/564
• Date Submitted 2008-07-07
• Source Kelvin Chou Kelvin.Chou_at_mediatek.com
• Yih-Shen Chen Yihshen.Chen_at_mediatek.com
• I-Kang Fu IK.Fu_at_mediatek.com
• Paul Cheng Paul.Cheng_at_mediatek.com
• MediaTek Inc. No.1, Dusing Rd. 1, Hsinchu
  Science-Based Industrial Park,
• Hsinchu, Taiwan 300, R.O.C.
• Venue IEEE 802.16m-08/024 Call for Comments
  and Contributions on Project 802.16m System
  Description Document (SDD)
• In response to the topic Upper MAC concepts and
  methods (mobility management)
• Base Contribution N/A
• Purpose To be discussed and adopted by TGm
  for the 802.16m SDD

2
Multi-Carrier Mobility Management Design Concept

• The MS may maintain its normal operations with
  the serving BS on one carrier (using one RF)
  while perform scanning or network re-entry to the
  target BS on another carrier (by another RF)

3
Scanning in Multi-Carrier System

• In cell reselection, the MS scans primary
  (fully-configured) carriers of neighbor BSs
• The MS may also scan other primary carriers of
  its serving BS

4
Scanning with Multi-Carrier Support (1/4)

• Scanning using the RF other than the one for its
  primary carrier
• The MS dedicates its secondary RF for either
  normal scanning or autonomous scanning
• In normal scanning, the scanning request/response
  messages can be exchanged over either the primary
  carrier or the secondary carrier
• Scanning operations go in parallel with normal
  operations on the primary carrier

5
Scanning with Multi-Carrier Support (2/4)

• An example of the MSC for scanning using
  secondary RF
• RF 2 is dedicated to scanning
• Scanning request/response can be exchanged via
  either carrier 1 or carrier 2

6
Scanning with Multi-Carrier Support (3/4)

• Scanning using multiple RFs simultaneously
• Perform DL channel evaluation and synchronization
  to multiple frequency bands via multiple RFs
  simultaneously
• To expedite the scanning operation (e.g. fast
  cell reselection)

7
Scanning with Multi-Carrier Support (4/4)

• An example of the MSC for scanning using multiple
  RFs simultaneously

8
Intra-Frequency Handover (1/5)

• Handover Scheme 1
• RF 1 primary carrier with S-BS until T-BS DL
  synchronization is done
• RF 2 DL synchronization (and initial ranging if
  possible) with T-BS
• Description
• The MS may use another RF (e.g. RF 2) to acquire
  the DL/UL channel parameters of the target BS
  (e.g. timing/frequency offset ) before
  disconnecting its primary carrier (e.g. on RF 1)
  from the serving BS
• After the DL/UL channel parameters are obtained,
  RF 2 may proceed to network reentry to the
  target BS, or it can pass the parameters to RF 1
  to complete network reentry
• Advantage
• Reduced handover interruption time

9
Intra-Frequency Handover (2/5)

• Handover Scheme 1 - Scenario 1
• The MS synchronizes with the target carrier (the
  primary carrier to handover to) of the target BS
  before disconnecting from the serving BS
• The MS maintains its primary carrier with the
  S-BS (e.g. using RF 1) and uses another RF (e.g.
  RF 2) to synchronize to the DL channel on the
  primary carrier of the T-BS and acquire the DL/UL
  parameters
• Remaining network reentry procedures (including
  initial ranging) are completed using RF 2 after
  the primary carrier to the S-BS has been
  disconnected

10
Intra-Frequency Handover (3/5)

• Handover Scheme 1 - Scenario 2
• The MS synchronizes with a fully-configured
  carrier of the target BS other than the target
  carrier before disconnecting from the serving BS
• The MS maintains its primary carrier with the
  S-BS (e.g. using RF 1) and uses another RF (e.g.
  RF 2) to perform initial ranging to a
  fully-configured carrier of the T-BS other than
  the target carrier
• Remaining network reentry procedures are
  completed using RF 1 after disconnecting from
  the S-BS
• The ranging parameters acquired by RF 2 (UL
  timing, power, etc.) are used by RF 1 to
  expedite its network reentry process

11
Intra-Frequency Handover (4/5)

• Handover Scheme 2
• RF 1
• Primary carrier with S-BS until new primary
  carrier with the T-BS is established
• Scheduled sleeping intervals
• RF 2 network reentry to the T-BS within
  sleeping intervals
• Description
• The MS puts its primary carrier (e.g. carrier 1)
  into sleep mode and uses another carrier (e.g.
  carrier 2) for network reentry to the target BS
  within the sleeping intervals of its primary
  carrier
• The primary carrier to the serving BS maintains
  connected until the new primary carrier to the
  target BS is established
• Advantage
• Make-before-break HO

12
Intra-Frequency Handover (5/5)

• An example of the MSC for HO scheme 2
• Primary carrier goes sleep upon receiving Fast
  Ranging IE
• RF 2 sends RNG_REQ within the sleep interval of
  the primary carrier

13
Inter-Frequency Handover (1/3)

• Handover Scheme 1 can also be used for
  inter-frequency handover
• RF 1 primary carrier with S-BS until initial
  ranging to the T-BS is done
• RF 2 initial ranging to the T-BS
• Description
• The MS synchronizes with the target carrier of
  the target BS before disconnecting from the
  serving BS
• The MS maintains its primary carrier with the
  S-BS (e.g. using RF 1) and uses another RF (e.g.
  RF 2) to perform initial ranging to the primary
  carrier of the T-BS
• Remaining network reentry procedures (including
  initial ranging) are completed using RF 2 after
  the primary carrier to the S-BS has been
  disconnected
• Advantage
• Handover interruption time is reduced

14
Inter-Frequency Handover (2/3)

• Handover Scheme 3
• RF 1 primary carrier with S-BS until new
  primary carrier with T-BS is established
• RF 2 network reentry to the T-BS
• Description
• Using the secondary RF (any RF other than the one
  for the primary carrier) for network reentry
• The primary carrier to the serving BS maintains
  connected until the new primary carrier to the
  target BS is established
• New primary carrier is established on the
  secondary RF
• Advantage
• Make-before-break HO

15
Inter-Frequency Handover (3/3)

• An example of the MSC for HO scheme 3

16
Summary of Multi-Carrier Handover Schemes

• Handover Scheme 1
• Intra-frequency handover
• Inter-frequency handover
• Handover Scheme 2
• Intra-frequency handover
• Inter-frequency handover
• Make-before-break handover
• Handover Scheme 3
• Inter-frequency handover
• Make-before-break handover

17
SDD Text Proposal
Add the following text into Session 10 of the SDD
(IEEE 802.16m-08/003) -----------------------
text begin ---------------------------------------
-------------------------------------- 10.x
Data/Control plane 10.x.y MAC Handover
Procedures 10.x.y.z Handover with Multi-Carrier
Support The MS may use a secondary RF (any RF
other than the one for the primary carrier with
its serving BS) to perform full or part of the
handover procedures. In this case, multiple RFs
can be used cooperatively to reduce the handover
interruption time or to achieve make-before-break
handover. ----------------------- text end
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