An Update from the LTE/SAE Trial Initiative

Transcription

1 Version January 2009 An Update from the LTE/SAE Trial Initiative ATIS LTE Towards Mobile Broadband January

2 Contents LSTI s Objectives Who s involved? LSTI Activities Latest results from Proof of Concept Group Updates from interoperability and trials Roadmap Summary 2

3 The LTE /SAE Trial Initiative The LSTI is an open initiative driven by Vendors and Operators launched in May 2007 Its objectives are to: Drive industrialization of 3GPP LTE/SAE technology Demonstrate LTE/SAE capabilities against 3GPP and NGMN requirements Stimulate development of the LTE/SAE ecosystem 3

4 LSTI Participants 21 LTE Equipment Vendors 8 Operators 4 representatives from across LTE s Global Ecosystem

5 LSTI Activities EPC Prototyping Interoperability Trials Applications Proof of Concept partially compliant IODT Stds compliant over key subset IOT Stds Compliant Trials Stds Compliant +form factor UE Network vendor + test UE or UE partner Network vendor+ UE partner pairs Multiple Partners Vendors and UE Operator + Network Vendor + UE partner Towards standards compliancy and commercial conditions 5

6 LSTI Internal Latest Results From the Proof of Concept Activity Demonstrating that basic LTE/SAE functionality and performance are achievable with pre-standards proprietary equipment 6

7 LTE/SAE: Proving the Concept EPC Lab Field Single Cell Single UE MIMO Multi UE Multi cell PoC has defined a set of proof points covering key aspects of functionality & performance (data rates, latency etc) Early tests are made over a single link in the lab. Later tests use more mature architecture and in more realistic conditions 7

8 The work of PoC Contributions are Consolidated into Messages 8 Measured results Performance requirements

9 Definitions of Proofpoint Status Proved in PoC reports for each proofpoint the number of company inputs and agrees on the status that the industry has reached: Each filled circle = 1 company input Initial Result Proved In Orange: Inputs of the correct format received. More needed to consolidate Can be presented as an initial result Green: Sufficient inputs received. PoC agrees Proofpoint is proved in Observed: LSTI Operators observed successful demonstration of this proofpoint 9

10 PoC Results Part 1) Data Rates How much will you get? 10 LTE is designed to deliver over 320 Mbps throughput But what can be achieved in practice? And what data rates will users actually experience? Part 2) Latency How quickly will you get it?

11 LTE working in the field LTE has been proved working in the field both in single cell and multi cell scenarios Single Cell -- Single Stream -- Dual Stream / MIMO Multi Cell Proved in MIMO working in the field Handover at speeds up to 100km/h 11 Tput Mbps 246Mbps on a drive test with 4x4 MIMO Mbps FTP restart HO HO 0 sec Mbps Tput on multicell drive test 2x2 MIMO 10MHz BW

12 Concise slide for 2009 presentations L1 pk rate, Mbps Mbps Peak Data Rates & Spectral Efficiency Peak rates are the top speed of the system achieved in optimal signal conditions with a single user in the cell Requirements are 100Mbps or 5bps/Hz for DL, and 50Mbps or 2.5bps/Hz for UL Measured Peak rates in lab and field meet the requirements Lab results Field results Reqrmt met LTE-FDD DL 4x4 DL 2x2 8.6bps/Hz UL 64QAM UL 16QAM 2.8bps/Hz Code rate results normalized to 20MHz bandwidth bps/hz TD-LTE Code rate DL 2x2 Proved in UL 64QAM UL 16QAM

13 So Will All Users Experience >100Mbps? Peak rate requirements apply to corner point conditions which can be verified by simulation or lab testing Actual rates that users experience will be impacted by: 13 Pk Rates Represent Corner Conditions Protocol Layer One UE/cell Optimal RF Phy layer UEs / cell Path Loss / UE Speed 1) RF conditions & UE speed Peak rates represent optimal conditions, lower rates are experienced towards the cell edge and when the UE is moving at high speed 2) Multiple users in the cell UE data rates will be lower when sharing the cell with others 3) Application Overheads Peak rate requirements apply to Physical layer. There will be overheads when considering data transfer between applications Impacts to UE rates are analysed in the following slides.

14 Radio Conditions Signal quality 100% Tput vs SNR typical example DL result Tput relative to peak 80% 60% 40% 20% 0% Cell edge SNR, db Near base Example results shown, similar behaviour observed for SM MIMO, SIMO and SFBC and UL SIMO Peak rates are achieved with high signal quality near the base station Tput is lower towards the cell edge 14

15 Radio Conditions UE Speed Proved-in 100% Tput vs SNR typical example DL result Tput relative to peak 80% 60% 40% 20% 0% Cell edge SNR, db 3 kmh 30 kmh 120 kmh 240 kmh 350 kmh Near base Example results shown, similar behaviour observed for SM MIMO, SIMO and SFBC and UL SIMO Resiliency of LTE prototypes to high user speeds is tested in the lab Initial results demonstrate support of up to 350km/h Little impact to throughput is seen at speeds up to 120km/h 15

16 Multiple Users per Cell - Downlink At any given instant, the cell s spectral resource is shared between all active users Proved-in Sharing of Downlink Tput L1 Tput, Mbps Lab test with flat AWGN channels Active Active UEs Idle UEs Frequency Selective Scheduling pwr UE1 UE2 frequency The scheduler can exploit different frequency responses of each UE s channel, to increase cell Tput Cell Tput Mbps UEs 1UE SNR (db) 16

17 Multiple Users per Cell - Uplink Proved-in Cell Tput depends on the mix of RF conditions for the active UEs Multi UE Uplink Tput with various mixes of RF conditions Mbps Med Med Med Good Good Poor Good Poor Poor Sharing of Uplink Throughput during a drive test 100% Active UEs Paired-up 17 Idle UEs The LTE Uplink has Multi-User MIMO, which pairs-up UEs to share the same UL resource to increase cell Tput % Usage MU-MIMO 0%

18 Throughput at the Application Layer Proved In Over-the-air bits Coding, Control, HARQ Ref signals MAC header L1- (PHY) Tput MAC Tput Not to scale RLC PDCP, IP & TCP/UDP headrs Application header TCP/UDP Tput Application Tput Lab measurement (10 MHz, SIMO) Field measurement (20 MHz, 2x2 MIMO) TCP Layer 1 Throughput requirements are specified at L1 (Physical Layer) Measurements show the difference between L1 & Application to be small for large packets (e.g. File Transfer) 18 Mbps SNR (db) L1 (AMC + HARQ) Application Layer Throughput [Mbps] Note IP packet size affects the amount of protocol overhead CDF [%] L1 APP

19 PoC Results Part 1) Data Rates How much will you get? Part 2) Latency How quickly will you get it? To provide an always on experience, LTE/SAE requires low delays for both user data and control of resources 19 Stopwatch by P.Neal

20 User-Plane Latency EPC Server Proved DRAFT in enb UE ping Measured Round Trip Times Industry targets Air interface End - End ms Low User-Plane latency is essential for delivering real time services, like gaming and VoIP Measured round trip times meet 3GPP and NGMN targets 20

21 Control-Plane Latency: Idle to Active time Proved in To provide many users with an always-on experience, LTE is designed with a low idle to active transition time All UEs sit in an idle state when there is no data to transfer but can be activated quickly when they need to communicate Measured Idle-Active Times Measured with one UE/cell 3GPP target 100ms Idle UEs idle active Active UEs ms 21 Measured idle to active times meet the 100ms requirement

22 VoIP Support Best effort loading Low delay 64kbps enb EPC Server with VoIP Test Tool Measured Performance in loaded conditions ms Packet Latency (one way) Jitter % =acceptable performance ms Packet Loss DRAFT Proved in Tests in ideal lab conditions have demonstrated that LTE/SAE is capable of providing IP connectivity with sufficient latency, jitter and packet loss performance to support good quality VoIP Operators have observed good quality VoIP in live air drive tests, including during handover 22

23 Handover Inter-eNB and intra-enb handovers demonstrated in the lab and field at up to 120 km/h Data interruption times under 50ms achieved, meeting NGMN s real time service requirement Both S1 and X2-assisted handovers demonstrated X2 Improves handover performance and reduces loading on MME Intra enb handover Proved in EPC: Gateway & MME Source enb S1 X2 S1 Target enb 23 Inter enb handover

24 LSTI Activity Timing Proof of Concept IODT preparation IOT preparation Friendly Customer Trials preparation PR/Marketing 24

25 An update from IODT Mission of IODT: Elaborate and recommend a minimum set of 3GPP R8 LTE/SAE Air Interface features to be implemented for the first stage of interoperability testing of the standards compliant LTE/SAE technology. Provide an overview of the progress of industry IODT for those features Basis for initial LSTI Friendly Customer Trials Status IODT features (I.e. Minimum Feature Set) agreed IODT Work Group working on recommended Test Scenarios Reporting on early interoperability during Q2-Q enb Uu 25

26 An update from IOT Mission of IOT: Elaborate and recommend a minimum set of 3GPP R8 LTE/SAE interface features for interoperability testing of the standards compliant LTE/SAE technology. Provide an overview of the progress of industry IOT on platforms intended for commercial use for those features. Report that interoperability of implementations of the essential features on platforms intended for commercial use has been proven. This implies that the standard has reached a sufficient state of stability. Strategy: Expand IODT minimum feature set Extra features for Air Interface testing S1 and X2 testing, requiring multiple RAN and EPC vendors Definition of associated Test Scenario recommendations Reporting expected after Q3-09 enb S1 X2 EPC S1 Uu enb 26

27 An update from Friendly Customer Trials Mission of FCT To visualize LTE capabilities and advantages in nearly commercial conditions with test applications provided by Vendors and 3rd parties. The friendly user trial phase shall enable Vendors and Operators to prepare for deployment and commercial launch Status Criteria for starting & reporting on Trial activities agreed Two phases : 1) Early testing of Radio access systems 2) Integration of EPC to enable End-to-end testing. Trial test cases will be based on LSTI feature set and NGMN field trial requirements 27

28 In Summary, The LTE/SAE Trial Initiative...is an open initiative of vendors and operators working together to accelerate the development of a global ecosystem for LTE..provides cross-industry co-ordination of prototyping, interoperability testing and field trials..is demonstrating that early LTE equipment is meeting industry requirements 28

29 Thank You 29