The Unlicensed Spectrum Usage for Future IMT Technologies Efficient LTE technologies enables better performance and experience

Transcription

1 The Unlicensed Spectrum Usage for Future IMT Technologies Efficient LTE technologies enables better performance and experience Huawei Technologies Co., Ltd HUAWEI TECHNOLOGIES CO., LTD.

2 Content WHY - Plentiful Resources but low Efficiency WHAT LTE on unlicensed spectrum How Key Tech. and Industry Development HUAWEI TECHNOLOGIES CO., LTD. Page 2

3 Plentiful Unlicensed spectrum assigned Not Ignore!! Others: Band Frequency Range (MHz) ISM ISM Unlicensed PCS Currently, the amount unlicensed spectrum assigned > the amount of licensed spectrum In the near future, more unlicensed spectrum are planned to be allocated Page 3

4 A Popular technology on unlicensed spectrum: WiFi vs. LTE Coverage comparison Peak rate comparison TD-LTE 5.9GHz 20dBm(38m) WIFI 5.9GHz 20dBm(28m) Low TD-LTE capacity is WiFi capacity is Low Protocol design LTE Pros. : Low Efficiency than LTE Overhead Higher efficient scheduling mechanism Better QoS insurance Uniform OAM& SON Better Security Mobility and service continuity Better power saving Simple but limited DL resource efficiency WiFi : 52.4% to 4.8% TD-LTE:61.2% to 38.1% WiFi:40.4%, 68.1% TD-LTE:30.9%, 33.3%. High Low Efficiency Unlicensed Spectrum is not fully used & Deployment is limited Page 4

5 Content WHY- Plentiful Resources but low Efficiency WHAT LTE on unlicensed spectrum How Key Tech. and Industry Development HUAWEI TECHNOLOGIES CO., LTD. Page 5

6 LTE on unlicensed spectrum - High Efficiency & Capacity complement The natural advantages of LTE can improve the usage of unlicensed spectrum Higher coverage Higher peak rate Lower overhead Higher Tx efficiency High Efficiency Capacity Complement As a good complement for LTE capacity, LTE on unlicensed spectrum can provide a better aggregating solution Unlicensed secondary carriers: as capacity/offload layers Control and management based on licensed primary carrier Inherit most of the merits of LTE: manageable/security/control/etc. Make it easy to adapt LTE into fully unlicensed utilization Here, LTE on unlicensed spectrum is named to U-LTE Page 6

7 Focuses on the Prioritized scenarios: Operator and Enterprise Main Application Scenarios for Unlicensed Spectrum Resident personal Public Operators Local Enterprise Solutions to be applied: WiFi self-evolution Carrier As secondary CR system As an integrated part of LTE licensed network, U-LTE is used in scenarios deployed by operators and enterprises. Page 7

8 Content WHY- Plentiful Resources but low Efficiency WHAT- LTE on unlicensed spectrum How Key Tech. and Industry Development Page 8

9 U-LTE: Basic Principles What to be inherited from the LTE merits Basic architecture: centralized scheduler & coordination between nodes Basic system BW, multiple access techniques (OFDMA on DL, SC-FDMA on UL) Basic numerology Basic mobility, security, QoS, etc. Fit unlicensed: Self-Protection Guarantee its quality of communication coexists with the other unlicensed systems, such as WiFi, Bluetooth, multiple nodes or devices of coexist closely without planning. Fit unlicensed: Fairness Guarantee the spectrum usage by the other unlicensed systems as fair as possible Page 9

10 U-LTE: Three Use cases Type 1: Pico with co-located Licensed & unlicensed CA Type 2: Macro with co-located or inter-site (with RRH) Licensed & unlicensed CA Type 3: Macro with co-located Licensed & unlicensed CA unlicensed spectrum has smaller range than licensed spectrum unlicensed spectrum has similar range with good Beamforming Note: The node transmission power is based on regulation requirements of Co-existence and Radiation safety Page 10

11 U-LTE: An integrated part of LTE licensed network 1. Secondary Carrier design Option 1: DL only unlicensed carrier (FDD Pcell or TDD Pcell ) Option 2: DL+UL unlicensed carrier (FDD Pcell or TDD Pcell Note: Pcell is Primary Cell Feasibility & Efficiency 2. Co-existence 2.1 Inter-operator interference 2.2 Inter-RAT system: Mainly WiFi Better Experience Implement the LTE valuable features (Mobility, QoS, security, ) through Pcell Explore the wide band resources on unlicensed spectrum It is beneficial to be compatible with the design of residential scenarios Page 11

12 Key point-1: Unlicensed Secondary carriers Design Option 1: DL only unlicensed carrier (FDD Pcell or TDD Pcell ) Option 2: DL+UL unlicensed carrier (FDD Pcell or TDD Pcell) If the QoS can be guaranteed, it is inclined to occupy unlicensed spectrum first. Page 12

13 Key Point-2.1: Inter operator interference Each operator has the equal right to access the unlicensed spectrum but without coordinated geographical isolation among different enodebs. Principal: Sensing or coordinating before using It is beneficial to coordinate the occupying and releasing spectrum among different operators Solution: Over-the air seems the only feasible way for coordination X2 or wired line are not available between different operators Static agreement can not be flexible Page 13

14 Key Point-2.2: Principal on Coexistence with WiFi Capacity Analysis : When the load become higher, the throughput of standalone WiFi decreases while the throughput of standalone LTE still increases due to the different scheduling mechanisms. 140 Http download (Mbps) TD-LTE DL WiFi DL Cell edge UPT (Mbps) 0 1 UE 2 UEs 3 UEs 4 UEs Besides the difference of scheduling mechanisms, due to HARQ, link adaptation based on receivers SINR, and periodic transmission of common channels in LTE, it is deduced that if LTE directly coexists with WiFi on the same unlicensed carrier, LTE will finally kick WiFi off when load is high. Page 14

15 Key Point-2.2: Suggestions on Coexistence with WiFi Friendly relations Less Protocol Changes LTE directly on unlicensed spectrum No change to current standard LTE on unlicensed spectrum with resource releasing after satisfy its own requirements Adaptive Cell on/off; Channel Hopping; Time muting; LTE on unlicensed spectrum with voluntary sacrifice More Sensing and conflict resolution; Resource coordination ; Flexible common channels; Fine time domain scheduling; Loose relationship between consequent transmissions, etc. Page 15

16 Industry Development: Business + Standardization + Chaining LTE on unlicensed spectrum (U-LTE) Build a Healthy Industry ecosystem for U-LTE Business: Cooperation with operators Make an available Business Model Standardization: Focus on 3GPP Scope: RAN technologies changes based on LTE RF coexistence study Timeline: Rel-13 Chaining: Cooperation with operators, infrastructure, chipset, terminal vendors etc. Drive a mature industry chaining for U-LTE Page 16

17 Summary Scenarios Technologies Industry Scenarios deployed by operators and enterprises are prioritized It is beneficial to be compatible with the design of residential scenarios Aggregating unlicensed spectrum as the secondary component carriers with the licensed carriers Both Self-Protection and Fairness should be guaranteed LTE can provide configurable different level of fairness Inter operator coexistence should be handled Explore the wide band resources on unlicensed spectrum Make an available business model with operators Standardization on RAN and RF technologies in 3GPP Drive a mature industry with operators, infrastructure, chipset, terminal vendors etc. LTE on unlicensed Spectrum (U-LTE) Page 17

18 Thank you! HUAWEI TECHNOLOGIES CO., LTD. Page 18