4.5G: boost the experience from user and operator s perspective. Dr. Guangyi Liu CMCC

Transcription

1 4.5G: boost the experience from user and operator s perspective Dr. Guangyi Liu CMCC

2 CONTENTS Progress of TD-LTE network Challenges for further development Expectation for further evolution Summary 2014/10/20

3 Progress on CMCC s TD-LTE network Base Station (10^4) 48 >50 (10^4) Subscriber 5,000 (10^8) Terminal up to now 2014 Total 2014 up to now 2014 Total 2014 up to now 2014 Total Network Largest LTE network at the end of 2014 International roaming with 8 operators Traffic Have balanced 13.4% traffics 4G ARPU:2 X average 4G DOU:6 X average Customer Much shorter access Latency to Internet Better experience for users with video services Globalization 41 TD-LTE commercial network globally Guarantee roaming based on robust ecosystem

4 Deployed Features Features deployed in the network Extended Scale Field Test 2012 Phase 1, 2013 Phase 2,2014 Features in Trial Configuration 20M/10MHz, 2DL:2UL,3DL:1UL 6:6:2 Carrier agg., Relay embms Multi-antenna TM3/8 adaptation IRC UL MU-MIMO 8Rx UL CoMP 8Rx TM9/DL CoMP RRM Mobility Static ICIC Interworking Others 4G/3G data reselection SON CSFB to GSM 4G/3G data redirection SON enhancement VoLTE with SRVCC 300km/h highspeed scenario Wireless big data embms, service Caching

5 CMCC TDL/TDS CT/CU PHS CT CDMA CU WCDMA CMCC TDS CT CDMA2x CU WCDMA CMCC TDL/TDS CMCC TDL CT CDMA CT CDMA CMCC GSM CU GSM CMCC GSM CU GSM CMCC GSM CU GSM TDD CMCC GSM CU GSM Converged FDD/TDD networking is a sufficient way for MBB FDD FDD Band 8: FDD Band 8: FDD Band 3: FDD Band 3: FDD Band 39:TDD Band 1: FDD B34: TDD Band 1: FDD Band 40: TDD Band 41: TDD FDD TDD Band 8: 900MHz 2x20MHz for GSM Band 3: 1800MHz 2x25MHz for GSM Band 34: MHz for TD-SCDMA Band 39: MHz for TD-SCDMA&TD-LTE Band 40: MHz for TD-SCDMA&TD-LTE (indoor only) Band 41: MHz for TD-LTE Note: MHz has limited applications for broadband wireless access, e.g. providing BWA service in some airports

6 Converged LTE TDD/FDD networking is in test TDD FDD Industry is mature enough for commercial deployment 3. LTE TDD/FDD joint operation 2. Load-balancing handover Object: utilize FDD/TDD resources simultaneously and maximize bandwidth efficiency 1.Coverage-based mobility management Object: Balance the load and increase bandwidth efficiency Object: Guarantee coverage and seamless service continuity For the first 2 phases, the industry is mature enough for commercial deployment The convergence can be further enhanced by deploying TDD/FDD joint operation in the near future

7 Performance in China Mobile Hong Kong (CMHK) Idle Reselection success rate: 100%, latency~31 ms Handover success rate 100% control plane latency : 16~18 ms user plane latency:55~56 ms Performance at the same level as inter-frequency handover within TDD or FDD Phase I: Coverage-based Mobility Management Industry & Commercial Deployment Status Well supported by both network equipment/terminal industry, ready for commercial deployment. All 5-mode or 4-mode smartphones can support handover between TD-LTE and LTE FDD since H2 of 2013 Already been enabled in more than 6 commercial networks Chipset Network Equipment Operator Enabled in>6 commercial networks

8 Phase II: Load-Balancing Handover In Industry Status Network equipment: well supported, ready for commercial deployment Terminal: no additional requirement needed as long as UE supports TDD/FDD handover, well supported Notes on Commercial Deployment Inter-Vendor Load-Balancing:Different vendors may have different definitions for load evaluation/user selection/user transfer/load information exchange, which might degrade the performance. Definitions needs to be unified to enhance user experience/network efficiency during load-balancing handover enb1 Load eval. User Selection &load transfer enb2 Response Status Request Response Status Response Response Status Update Handover Request Handover Response Standardization regarding inter-vendor load-balancing have been done in both 3GPP and NGMN. Industry promotion can be done when needed

9 Phase III: Joint Operation Scenario 1 TDD-FDD co-baseband, single vendor Solution: TDD-FDD Carrier Aggregation Scenario2 TDD-FDD non-co-baseband, multi-vendor Solution: TDD-FDD Dual Connectivity Benefits TDD/FDD Dual-mode enb FDD Carrier TDD Carrier TDD/FDD Dual-mode UE (Single Tx) TDD enb TDD Carrier TDD/FDD Dual-mode UE (Double Tx) Non-ideal backhaul (e.g., X2) FDD Carrier FDD enb Peak data rate (theoretical): 20M TDD+20Mx2 FDD = 260 Mbps Dynamic load balance (CA, ~ms level): 10% cell average throughut (simulation) 30% cell edge throughput (simulation) Standardization Progress & Industry Status Standard Progress: Both TDD-FDD CA and Dual Connectivity are ongoing in 3GPP R12; Industry status: Initial PoC and field trial has been done by some network vendors; Freq. Finished B8(900M)+B40(2.3G) B1(2.1G)+B42(3.5G) B19(850M)+B42(3.5G) Ongoing B1(2.1G)+B41(2.6G) B3(1.8G)+B40(2.3G) B26(850M)+B41(2.6G) B3(1.8G)+B41(2.6G)

10 Industry Status of TDD-FDD Joint Operation PoC demo of TDD-FDD CA in MAE 2014 TDD-FDD CA enhance peak data rate Field Trial of Dual connectivity in Shanghai MSA enhances the peak data rate and cell-edge throughput Peak data rate Cell-edge throughput TDD as Pcell:DL peak data rate 250Mbps FDD as Pcell:DL peak data rate 250Mbps MSA balance load between Macro and small cell by load and inteference condition Balance by load Balance by interference 20M TDD config.2 (band41)+ 20*2 FDD(band8); Both TDD and FDD can be configured as Pcell; 10M TDD (3.5G)+ 10*2 FDD (2.6G);

11 CONTENTS Progress of LTE network Challenges for further development Expectation for further evolution Summary 2014/10/20

12 New Challenges for CMCC High data rate Traffic booming Delay sensitive Always online Seamless mobility Densified deployment Heterogeneous architecture Multi-RAT co-existence Various terminal types 2014/10/20

13 Challenges for TD-LTE Network Coverage High frequency band cause big path loss Hard to obtain or to get site locations for macro cells Challenges Insufficient deep indoor coverage,high cost by deploy DAS Co-exist of multi-band and multi-system need to be considered Flexible enb types would be helpful!

14 Flexible enb types is the way for deep coverage Macro coverage dead spot and hot spot coverage Public indoor coverage Home coverage Macro cell Micro cell Pico/Nanocell Nanocell Macro RRU Active antenna Micro RRU Small Cells BBU Integrated micro Enterprise Nanocell Residential Nanocell Distributed macro Relay BBU Distributed micro Pico RRU Micro repeater

15 Small Cells become extremely important Mobile data traffic exploding High capacity demand Multi-layer architecture More small cells have to be deployed ~5X small cells vs. macro cells without new frequency introduced ~3X small cells vs. macro cells with new frequency introduced Urban Village/Town Macrocell Rural DAS Pico/Nanocell Macrocell Relay Micro Microcell Pico/nano Micro Pico/nanocell Relay Macrocell Microcell

16 Challenges for Small Cell application Complex interference control & mobility management More dependent on SON Others? Multi-mode support Cost control O&M Business model

17 CONTENTS Progress of LTE network Challenges for further development Expectation for further evolution Summary 2014/10/20

18 Key Issues Remained for Further Study Explore the potentialities of convergence, e.g. multi-rat coordination, TDD/FDD joint operation based on CA and DC etc. Spectrum Find new resources, e.g. unlicensed Automatically respond the metrics required by operators, e.g. SINR, VoLTE related Network Capability Improve the capability, e.g. UL64QAM, multiple CC aggregation More accurate and service-aware management, e.g. RAN caching, traffic localization, etc. Voice related optimization, e.g. CSFB, VoLTE, etc. Voice and SON Improve the deep coverage, e.g. dense small cell Deep Coverage Improve the special coverage, e.g. high rise building, etc.

19 Converged Network to boost the user experience The first and second phase of FDD/TDD convergence has been tested, and coverage based handover and load balance could be introduced Load Increasing I:Coverage Based II:Load Balancing Spectrum Flexibility CA & DC III:FDD/TDD Joint Operation Evolution MRC Controller MRC (Multi-RAT Connectivity) Joint Radio Resource Allocation 2G 3G Multi-RAT Management 4G Traffic Steering WLAN

20 Licensed Assisted Access Unlicensed spectrum requirements 687MHz has been allocated in China Not so much potential spectrum available for IMT below 6GHz Spectrum will be the most important aspect for IMT development How to use the unlicensed band? YEAR Spectrum Requirements China MHz MHz U.S MHz Australia MHz Russia MHz GSMA MHz ITU MHz Carrier Aggregation Licensed Band Standalone Unlicensed Band Perform interference handling Avoid congestion on unlicensed band Guarantee QoS Separate signaling and data Possible for normal UE to deploy LTE Hard for interference handling Carrier Aggregation is supposed to be the only solution for LAA at least in R /10/20

21 UL Enhancement Spectral efficiency limitation for uplink transmission E.g., maximum 16QAM or 64QAM, which limits higher transmission spectral efficiency regardless higher transmission power Tx EVM limits higher SINR at receiver side, which limits higher transmission spectral efficiency For example, ~90% users has SINR higher than MCS_16 - Assuming maximum 16QAM, 1Tx8Rx ~50% users has SINR higher than MCS_16 - Assuming maximum 16QAM, 1Tx2Rx 16QAM,8Rx Possible enhancement, especially for good SNR users Uplink Dual Transport Blocks (TB) transmission for 1Tx UE (UL_1Tx_dualTB) can offer gains from uplink peak data rate and spectral efficiency perspective[1] Utilization of uplink 64QAM (UL_64QAM) [2] Note: [1] RP New Work Item Proposal: support of uplink 64QAM in LTE Huawei, HiSilicon [2] RP Uplink dual transport block transmission to enhance uplink performance CMCC

22 3D-MIMO UMa/UMi Highrise Indoor RX RX TX RX 2D-MIMO 3D-MIMO Increased receive energy Wide beam in elevation domain Narrower beam in elevation domain Fixed downtilt Reduced inter-cell-interference Larger downtilt for cell-center user Serve more users simultaneously Can separate users in horizontal domain only Can separate users in both horizontal and vertical domain

23 Service-Aware Management The aim is to improve the radio access control and user data transmission in a differentiated manner on a service-aware basis. VoLTE M2M OTT Video Control signaling access enhancement User data management optimization Service localization RAN Caching Service continuity SCM: Smart Congestion Management Differentiate the radio access probability UPCON: User Plane Congestion management Differentiate the user data transmission LIPA/SIPTO Differentiate the local service provision and routing Popular service cached in RAN side Reduce backhaul and Core load Adaptive service distribution and convergence Consistent service experience Finer gratuity of QoS handling w.r.t. signaling and user data treatment

24 Small Cell Enhancement 256QAM 34% peak throughput gain vs. 64QAM Average spectrum efficiency 16% Radio-Interface Based Synchronization Maximum +/- 1.5us timing error supporting 4 stratum levels Supporting network listening between inter-vendor small cells Small Cell On/off and discovery Energy saving, interference mitigation, off-loading Average spectrum efficiency 10% Dual connectivity User peak throughput 90% Better user mobility Small cell cluster Cell discovery 4 Macro enb Small cell on/off Cell 1 (on) Cell2 (off) Cell 3 (off) Cell 4 (on) Cell 5 (off) 256QAM Macro enb Carrier 1 User Plane Data Non-idea backhaul (e.g.,x2) Dual Connectivity Carrier 2 User Plane Data Small cell

25 MDT Enhancement The general motivation of MDT Decrease the cost of drive testing Avoid additional emission of CO2 Extend time and space for drive testing Motivation VoLTE: Deployment of VoLTE of most operators is this year SINR: Be used to detect coverage problems and access network performance Towards emdt Specify VoLTE and video related measurements and corresponding collection. Specify SINR-like measurement and collection

26 Voice Related Enhancement CSFB VoLTE CSFB: UE automatic fast return after CSFB to GSM Save the delay of returning LTE (about s), while the cell reselection delay is more than 40s Standardization needed, both CSFB to GSM and 3G VoLTE SPS: Unsatisfied Performance Standard limitation on max MCS (below 15) Scheduler has to be prepared for long term (e.g.200 ms) RF condition thus sacrifice too much radio resource Clarification needed for SPS + C-DRX esrvcc: long preparation time & interruption time prep time(asking 2G for resource reservation) takes 1-2s due to long signaling chain, making HO vulnerable to failure User plane interruption time up to 800ms, optimization needed

27 CONTENTS Progress of LTE network Challenges for further development Expectation for further evolution Summary 2014/10/20

28 Summary Converged FDD/TDD networking becomes a trend Heterogeneous network is the flexible way for deep coverage and capacity expansion Further enhancement is expected to boost the network capacity and user experience simplify the network optimization and maintenance 2014/10/20

29 THANKS!