DOCUMENT #:
GSC13-PLEN-41
FOR:
Presentation
SOURCE:
Huawei Technologies Co., Ltd
AGENDA ITEM:
Plenary; 6.1
CONTACT(S):
dmyglz@huawei.com
Evolution road of 3GPP-LTE
Huawei Technology Co., LTD
Submission Date:
July 1, 2008
Highlight of Current Activities (1)
• Developing the standard on the evolution of the 3G mobile system
– The evolution of the 3G radio-access technology towards a high-datarate, low-latency and packet-optimized.
– The main work of LTE focuses on:
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Architecture
eNB function
Radio interface
Band arrangement
Transmission scheme
RF related requirements
Mobility and RRM
SON
Support of Interworking between LTE and 3GPP RAT or 3GPP2 RAT
– Currently focusing on LTE Stage 3 (finishing LTE Rel-8 specification)
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Highlight of Current Activities (2)
• Currently specifications completion level
Transmission scheme
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Multiple Address（100％）
Downlink: OFDMA Uplink: SC-FDMA
Frame Structure （100％）
Modulation（100％）
Coding（100％）
Physical procedure(99%)
Radio interface and
protocols
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MAC(80%)
RLC(70%)
RRC(70%)
Architecture and
protocols
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Architecture and Interface Protocol Structure(100%)
RRM(90%)
O&M(100%)
SON(70%)
MM(99%)
RF related , band
arrangement
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RF related requirement, the requirement support
of RRM (80%)
LTE repeater(25%)
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Strategic Direction
• Growing experience with the take-up of 3G is helping to clarify the likely
requirements of users, operators and service providers in the
longer term
• LTE project aims to ensure the continued competitiveness of the 3GPP
technologies for the future
• The LTE standards development had been defined in the following
phases:
– SI phase: finished at the Sep, 2006
– WI phase: started at the June, 2006
– Currently it is in Stage 3 in WI phase. It is expected to launch the first
LTE commercial version standard by the end of 2008.
• In 2009, the work will focus on the enhancement and Improvement of
LTE.
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Challenges
• LTE business development and business model need more deep
consideration because of HSPA+ and Wimax.
• With HSPA (downlink and uplink), UTRA will remain highly competitive for
several years, most of operators are deploying 3G (UMTS/HSPA)
network but have little income, it will be solved firstly.
• LTE performance can not be satisfied by some operators. So LTE
system will be continued to be improved to fulfill the operator’s
different requirements.
• The final choice of LTE technologies is not simply technological, it may
be determined ultimately by IPR issues, there isn’t a IPR solution till now.
• There are so many players in 3GPP which will take some difficulties to
average benefit, So the schedule of LTE has been strongly delayed, It
will be completed on Dec 2008.
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Next Steps/Actions
• Begin the Study Item of LTE-Advanced, It shall be an evolution of LTE.
– LTE terminal shall be supported in LTE-advanced networks
– an LTE-Advanced terminal can work in an LTE part of the network
• Allow coverage ranging from Macro cells to indoor environment such
as Home coverage
• Primary focus of LTE-Advanced is low mobility users
• Self-configuration and optimization shall be further enhanced
• Features already supported in previous releases are a pre-requisite for
being supported by LTE-advanced
• LTE-advanced shall support FDD and TDD mode of operation with
maximum commonality
• Cost reduction
− Low cost of the infrastructure deployment and terminal for LTEadvanced shall be an essential element
− Power efficiency in the infrastructure and terminal shall be an
essential element
− Backhauling shall minimize cost per bit
• Minimizing additional complexity for the terminal
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Proposed Resolution
• N/A
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Supplemental Slides
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Huawei’s activities in LTE
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Huawei is one of the pioneer companies who proposed the creation of LTE. We
now have plenty of important proposals accepted involving in physical layer,
high layer, interface and performance.
Huawei is the editor of TS36.411 and TS36.421 of LTE specifications.
Research view over the key issue:
– Downlink OFDMA
• Intra-cell Orthogonality
• High spectra efficiency
– Uplink SC-FDMA
• Promising uplink multiple access scheme with higher terminal Power
Amplifier efficiency
– Soft frequency reuse
• suppress the inter-cell interference
• improve cell edge data rate
– MIMO
• Higher average throughput and spectral efficiency
– MBMS on LTE
• Efficient Broadcast and Multicast transmission on LTE system
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LTE: Huawei research points
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Downlink OFDMA
– Fast hopping pilot pattern
– Multiplexing frequency diversity and Multi-User diversity transmission
– AMC process for DL Link Adaptation
– PAPR Reduction
Uplink SC-FDMA
– Distributed pilot design for localized data
– HARQ for UL
– CQI Report mechanism
Inter-cell Interference Mitigation
– Soft Frequency Reuse
• Major frequency with reuse factor greater than 1at cell edge
• Minor frequency with reuse factor 1 in near Base Station
• Major frequency bands coordinated with neighboring cells
MIMO & Transmit Diversity
– MU-MIMO
– Combination CDD (Cyclic Delay Diversity) and STTD
– MIMO for MBMS
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LTE: Huawei research points
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RRC functions
– RRC states
• Location of the Upper RRC and lower RRC
• RRC terminated in ENB, but some functions such as PDCP control etc.
should be in aGW
– LTE_Active mobility
• Handover method: data forwarding and bi-casting or mixed method
• Handover executing on ENB
• Should consider power saving mode
– LTE_Idle mobility
• Cell selection and re-selection
• Mobility handled in aGW
– Measurement
• Measurement gap decided and coordinated by UE and ENB
• Measurement controlled by ENB (opportunity, control, report, )
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LTE: Huawei research points
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MAC functions
– Outer ARQ
• Located in ENB
• One or more ARQ entities for one UE
• Outer ARQ operation should be based on segmented/concatenated
upper layer PDU
• Re-segmentation/re-concatenation is supported
• Adaptive header structure of ARQ PDU and status report should
contain segmentation information
• Status report scheme should be reserved and simplified in LTE
• Some HARQ and ARQ function could be merged. For example, only
one sequence number is used and only one re-ordering function in the
receiver.
– MAC architecture
• There is only one MAC entity per cell, UL shared channel and DL
shared channel should use joint scheduler.
• Segmentation/ concatenation should use scheduling information.
• Async. HARQ may be considered
• Multiplexing data from different UEs into one block should be avoided
• More than one Transport Blocks could be transmitted during one TTI
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