mbms support in e-utran - march 2011
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TRANSCRIPT
© 3GPP 2009 Mobile World Congress, Barcelona, 19th February 2009© 3GPP 2011 MBMS support in E-UTRAN, March 16th 2011 1
Thomas Sälzer (Huawei Technologies, LTE MBMS rapporteur)
Version 1.0
MBMS support in E-UTRANMBMS support in E-UTRAN
3GPP-DVB Workshop RCD-11002Kansas City, USA16th March 2011
© 3GPP 2009 Mobile World Congress, Barcelona, 19th February 2009© 3GPP 2011 MBMS support in E-UTRAN, March 16th 2011 2
LTE-MBMS MBSFN principle
Multicast/Broadcast over a Single Frequency Network (MBSFN)• Simulcast transmission technique realised by transmission of identical
waveforms at the same time from multiple cells. • An MBSFN transmission from multiple cells within an MBSFN Area is seen as a
single transmission by a UE.• MBSFN reception is possible in connected and idle states independent of
incoming or outgoing calls.
From "LTE – The UMTS Long Term Evolution"Sesia, Toufik, BakerJohn Wiley & Sons
© 3GPP 2009 Mobile World Congress, Barcelona, 19th February 2009© 3GPP 2011 MBMS support in E-UTRAN, March 16th 2011 3
Overview of MBMS support in E-UTRAN
Supported from Rel-9• Shared carrier deployments (TDM on sub-frame level shared with unicast)• Semi-Static MBSFN areas with possible overlap• Downlink only transmission (no feedback channels)
Supported from Rel-10 • Counting of MBMS interested UEs in connected mode• Semi-static activation/deactivation of eMBMS session per MBSFN area
Further work on service continuity is foreseen for Rel-11• Mobility (cell selection/reselection and handover)
© 3GPP 2009 Mobile World Congress, Barcelona, 19th February 2009© 3GPP 2011 MBMS support in E-UTRAN, March 16th 2011 4
MBMS service area
MBMS Service Area
MBSFN Area
MBSFN Area
MBSFN Area
MBSFN Area Reserved Cell
© 3GPP 2009 Mobile World Congress, Barcelona, 19th February 2009© 3GPP 2011 MBMS support in E-UTRAN, March 16th 2011 5
MBMS channels Downlink channels related to MBMS
• MCCH Multicast Control Channel• MTCH Multicast Traffic Channel• MCH Multicast Channel• PMCH Physical Multicast Channel
Multiplexing of MBMS and unicast is realized in the time domain onlyMCH is transmitted over MBSFN in specific subrames on physical layerMCH is a downlink only channel (no HARQ, no RLC repetitions)• Higher Layer Forward Error Correction (see TS26.346)
A single transport block is used per subframeDifferent services (MTCHs and MCCH) can be multiplexed The MCS of each MCH is fixed in the MBSFN area and selected by the network
© 3GPP 2009 Mobile World Congress, Barcelona, 19th February 2009© 3GPP 2011 MBMS support in E-UTRAN, March 16th 2011 6
Frame structure for shared carriers TDM principle • MBSFN is not transmitted in subframes 0, 4, 5 and 9 (FDD)
and subframes 0, 1, 2, 5, 6 (TDD)• The subframe ratio available for MBMS ranges from 1/320 to 192/320• A 10/40ms pattern repeats over {1, 2, 4, 8, 16, 32}radio frames
Single MBSFN subframe contains single cell control part and MBSFN part
MBSFN RS + MBMS Data
One Subframe
RS
/PC
FIC
H/
PD
CC
H/P
HIC
H
Single cell transmission Multi-cell transmission
1 ms
© 3GPP 2009 Mobile World Congress, Barcelona, 19th February 2009© 3GPP 2011 MBMS support in E-UTRAN, March 16th 2011 7
Main characteristics of MBSFN
Transmission scheme OFDM
Channel bandwidths 1.4, 3, 5, 10, 15, 20 MHz
Carrier spacing 15 kHz
Guard interval 16.7 us
Modulation schemes QPSK, 16QAM, 64QAM
MIMO scheme single antenna port
Transport block transmission duration 1 ms
Number of coded blocks per transport block Variable
Typical transmit powerThe eNodeB (Macro cells) maximum transmit power is left to
implementation, but most coexistence analyses assume Macro Tx Powers around 40W (46dBm)
© 3GPP 2009 Mobile World Congress, Barcelona, 19th February 2009© 3GPP 2011 MBMS support in E-UTRAN, March 16th 2011 8
Reference signals
0l 5l 0l 5l
even-numbered slots odd-numbered slots
Antenna port 4
4R
4R
4R
4R
4R
4R
4R
4R
4R
4R
4R
4R
4R
4R
4R
4R
4R
4R
extended cyclic prefix, 15kHz carrier spacing
Single antenna portClose frequency spacing to support larger delay spreads
© 3GPP 2009 Mobile World Congress, Barcelona, 19th February 2009© 3GPP 2011 MBMS support in E-UTRAN, March 16th 2011 9
Performance of MBSFN
Summary of MBSFN performance, dedicated carrier (TR 25.912)
Deployment Spectrum Efficiency[bps/Hz]
Inter-site Distance @ 1bps/Hz[m]
Case 1 3.13 1619
Case 2 3.02 2310
Case 3 0.99 1619
Case 4 3.18 4375
Case Band(MHz)
Site to site distance(m)
Speed(kph)
1 2000 500 3
2 2000 500 30
3 2000 1732 3
4 900 1000 3
Simulation assumptions:
R1-070674: "LTE physical layer framework for performance verification" Orange, China Mobile, KPN, NTT DoCoMo, Sprint, T-Mobile, Vodafone, Telecom Italia.
© 3GPP 2009 Mobile World Congress, Barcelona, 19th February 2009© 3GPP 2011 MBMS support in E-UTRAN, March 16th 2011 10
Alternative MBSFN numerology
0l 2l 0l 2leven-numbered
slots
Antenna port 4
4R
4R
4R
4R
4R
4R
4R
4R
4R
odd-numberedslots
4R
4R
4R
4R
4R
4R
4R
4R
4R
extended cyclic prefix, 7.5kHz
Physical layer specifications contain an alternative numerology for dedicated carriers
Alternative numerology• 7.5 kHz carrier spacing• Longer guard interval of 33.3us• Reference signals as shown
This option is currently not fully supported• No related signalling• No related performance requirements
© 3GPP 2009 Mobile World Congress, Barcelona, 19th February 2009© 3GPP 2011 MBMS support in E-UTRAN, March 16th 2011 11
MBMS overall architecture
BMSC (broadcast multicast service center): provides functions for MBMS user service initiation and deliveryMBMS-GW (MBMS gateway): broadcasts MBMS packets to each eNB transmitting the service on M1 interfaceMCE (Multi-cell Coordination Entity)• Allocates or not the radio resources used by eNBs in the same MBSFN area• Configures MBSFN subframes for MBMS control and data broadcast• Ensures that the L2/L3 layers in eNBs are well configured for MBSFN operation• Determines the MCS for PMCH
UE eNB
MME
BMSCMBMS GW
MCE Content Provider
M2
M1
Sm
SGi-mb
SGmb
M3
© 3GPP 2009 Mobile World Congress, Barcelona, 19th February 2009© 3GPP 2011 MBMS support in E-UTRAN, March 16th 2011 12
MBMS RAN interfaces
Control plane interfaces• M3, M2 interface are control plane interfaces• M3 between MME and MCE carries MBMS session management
signaling• A MCE is connected to all eNBs within the same MBSFN area
through M2 interface mainly for MBMS session management signaling and radio configuration signaling
User plane interface• M1 interface is a user plane interface (no uplink data and no
control plane)• A MBMS GW is connected to multiple eNBs through M1 interface
for data distribution• IP multicast is used to deliver the downlink packets and SYNC
protocol is used over the M1 interface to keep the content synchronization
© 3GPP 2009 Mobile World Congress, Barcelona, 19th February 2009© 3GPP 2011 MBMS support in E-UTRAN, March 16th 2011 13
MBMS services and higher layer protocol stack
RTP PayloadFormatsMIKEY
KeyDistribution
(MTK)
MBMS SecurityMBMS Security
KeyDistribution
(MSK)
FLUTE
IP (Multicast) or IP (Unicast)
UDP
StreamingCodecs (Audio,
Video, Speech, etc.)
Download3GPP file format, Binary data, Still
images, Text, etc.
MBMS or ptp Bearer(s)
Service Announcement & Metadata (USD,
etc.)
Application(s)
FECHTTP
TCP
IP (unicast)
ptp Bearer
ptp FileRepair
Reception Reporting
MIKEY
Associated-DeliveryProcedures
Registration
RTP/RTCP
UDP
Service Announcement
& Metadata (USD, etc.)
Associated-Delivery
Procedures
ptm FileRepair
HTTP-digestSRTP
FEC
Different MBMS user services can be provided on multi-cast or uni-cast bearers• HTTP• File download• Audio/Video streaming
The figure shows the related higher layer protocol stacks (TS26.346).
© 3GPP 2009 Mobile World Congress, Barcelona, 19th February 2009© 3GPP 2011 MBMS support in E-UTRAN, March 16th 2011 14
Main referencesFeasibility study for evolved Universal Terrestrial Radio Access (UTRA) and Universal Terrestrial Radio Access Network (UTRAN)http://www.3gpp.org/ftp/Specs/html-info/25912.htmEvolved Universal Terrestrial Radio Access (E-UTRA) and Evolved Universal Terrestrial Radio Access Network (E-UTRAN); Overall description; Stage 2http://www.3gpp.org/ftp/Specs/html-info/36300.htmEvolved Universal Terrestrial Radio Access (E-UTRA); Physical channels and modulation http://www.3gpp.org/ftp/Specs/html-info/36211.htmEvolved Universal Terrestrial Radio Access (E-UTRA); Radio Resource Control (RRC); Protocol specificationhttp://www.3gpp.org/ftp/Specs/html-info/36331.htmEvolved Universal Terrestrial Radio Access Network (E-UTRAN); General aspects and principles for interfaces supporting Multimedia Broadcast Multicast Service (MBMS) within E-UTRANhttp://www.3gpp.org/ftp/Specs/html-info/36440.htmMultimedia Broadcast/Multicast Service (MBMS); Protocols and codecshttp://www.3gpp.org/ftp/Specs/html-info/26346.htm
© 3GPP 2009 Mobile World Congress, Barcelona, 19th February 2009© 3GPP 2011 MBMS support in E-UTRAN, March 16th 2011 15
Thank you !