Freescale, the Freescale logo, AltiVec, C-5, CodeTEST, CodeWarrior, ColdFire, ColdFire+, C-Ware, the Energy Efficient Solutions logo, Kinetis,

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1 Freescale, the Freescale logo, AltiVec, C-5, CodeTEST, CodeWarrior, ColdFire, ColdFire+, C-Ware, the Energy Efficient Solutions logo, Kinetis, mobilegt, PowerQUICC, Processor Expert, QorIQ, Qorivva, StarCore, Symphony and VortiQa are trademarks of Freescale Semiconductor, Inc., Reg. U.S. Pat. & Tm. Off. Airfast, BeeKit, BeeStack, CoreNet, Flexis, Layerscape, MagniV, MXC, Platform in a Package, QorIQ Qonverge, QUICC Engine, Ready Play, SafeAssure, the SafeAssure logo, SMARTMOS, TurboLink, Vybrid and Xtrinsic are trademarks of Freescale Semiconductor, Inc. All other product or service names are the property of their respective owners Freescale Semiconductor, Inc. TM

2 Course is addressed to students in 3 rd grade or above Students will not have to choke on deeply technical notions Students get to know about the field of designing and engineering in DSP for Telecom Introduce ETTI students into the magic world of 4G, from the engineer perspective, not just as a consumer Freescale is setting up future sessions for you with Telecom experts Courses, free discussions, research projects etc. Your feedback is highly welcome! TM 2

3 You will understand what 4G means and what makes it so special. You will become familiar with LTE terminology. You will have an overview of LTE physical layer (Layer 1) and understand what kind of operations and activities are going on inside a system on-chip at L1 level. You will learn essentials of optimizing the system throughput. You will understand that implementing a base station requires a lot of engineering talent. TM 3

4 Andrei Alexandru Enescu Academic Professor at University ( ) Ph D degree in the field of MIMO in Modern Wireless Communication Systems Currently invited professor for CSIC master program, with two courses: Software Defined Radio DSP for HDL Industry Past PHY Team lead at Redline Communication Cross-layer optimization and DSP Team manager at Freescale Semiconductors for L1 Currently Wireless Access System Engineer at Freescale Semiconductors for LTE and WCDMA projects TM 4

5 Nice to meet you! TM 5

6 Lecture 1 What is LTE? Cellular deployment Network architecture 4G market and perspectives Lecture 2 LTE radio interface TDD vs. TDD Flexible bandwidth Frame structure Performance figures QoS impact on L1 Lecture 3 Processing chain Block diagram of a NodeB Small vs. Macro cells Key hardware accelerators Multi-standard terminal TM 6

7 LTE represents the migration from voice-centric transportation infrastructures to a fully packet switched, flat IP network model Next generation communication standard Following the traces of GSM, EDGE, UMTS LTE addresses mobile market needs in terms of services (capacity, latency, flexible network) Encourages evolving of new services (e.g. collaborative realtime video games, video sharing, video conferences etc.) TM 7

8 Mobile traffic will reach 6.3 exa bytes (1 EB = B) in 2015 * 8 One word: VIDEO Mobile traffic *Source: Cisco VNI Mobile TM 8

9 Interactive TV Mobile video blogging Advanced video games Video apps Professional services TM 9

10 Mobile traffic by EB 108% annual increase Average smartphone will generate monthly traffic of 1.3GB 65% of all traffic is video It s all about mobility *Source: Cisco VNI Mobile 2012 TM 10

11 What does the mobile market want? More throughput Larger bandwidth Up to 100MHz Enhanced technologies OFDM, MIMO, SC-FDMA Smaller latency Increased security Traffic-revenue gap becomes larger and larger Limit the traffic Optimize costs TM 11

12 3G - UMTS How is it Performance Network Throughput DL/UL balance Latency Hierarchical 300Mbps on DL and 75Mbps on UL 4:1 2 sec on first connection 50ms afterwards Slow, expensive We need much more than that Very unbalanced not suitable for Interactive video, advanced gaming and other video services Way too slow! Possible improvement Shift to flat network (all IP) More bandwidth Better technologies Enhance technology over UL Shift to flat network (all IP) TM 12

13 All-IP flat network No more hierarchical aggregation of user data User core router is linked to the central core router We benefit from: Smaller latency Reduced number of elements in the network Reduced OPEX (OPerational EXpenses) More decoupling between radio access network from core network New technologies at L1 level TM 13

14 RNC Circuit switched zone NodeB Iur UMTS Iu-PS Iub RNC SGSN Packet switched zone enodeb X2 S1 EPC Packet switched zone LTE enodeb TM 14

15 3G - UMTS How is it Performance Network Throughput DL/UL balance Latency Hierarchical 300Mbps on DL and 75Mbps on UL 4:1 2 sec on first connection 50ms afterwards Slow, expensive We need much more than that Very unbalanced not suitable for Interactive video, advanced gaming and other video services Way too slow! Possible improvement Shift to flat network (all IP) More bandwidth Better technologies Enhance technology over UL Shift to flat network (all IP) Smaller latency Reduced cost along with increasing traffic Flexible network TM 15

16 Modulation Mapping bits onto symbols from a predefined set MIMO Using multiple antennas to transmit independent streams Streams may be used to better encode the signal and gain more robustness Carrier aggregation Achieving higher bandwidth TM 16

17 Group several bits into a symbol QPSK: 2 bits/symbol 16QAM: 4 bits/symbol 64QAM: 6 bits/symbol Radio channel alters the transmitted symbol Receiver decides which is the most likely symbol transmitted based on proximity Increasing rate means choosing over a denser constellation This comes at the price of being less robust on the radio channel QPSK example b 0 b s 0-1+j 16QAM TM 17

18 Transmitter has multiple antennas It can transmit independent streams over each antenna Make sure each antenna has a different propagation path than the others Paths must be decorrelated Receiver must have the same number of antennas or larger Complex decoding algorithms Tx Channel Rx TM 18

19 In LTE-A, bandwidth will go up to 100MHz Aggregates bands UE (Mobile terminal) is unaware Backwards compatibility with Rel 8/9 terminals 5MHz 10MHz 20MHz TM MHz

20 Technology MIMO Using multiple antennas to transmit independent streams Streams may be used to better encode the signal and gain more robustness CoMP (Coordinated MultiPoint Diversity) Mobile terminal at the cell edge may receive signal from two different base stations HARQ (Hybrid Automatic Repetition Request) Retransmission at the L1 level using different transmit patterns TM 20

21 HSPA+ still struggles to keep in the game (Nokia Siemens) Import the same technologies as in LTE Standard HSPA Rel 5 HSPA Rel 11+ LTE Rel 8 LTE A Rel 11 Max bandwidth MIMO Max modulation Peak rate 5MHz DL: 40MHz UL: 10MHz - DL: 2x2 UL: 2x2 DL: 16QAM UL: QPSK DL: 14.4Mbps UL: 5.76Mbps DL: 64QAM UL: 64QAM DL: 672Mbps UL: 70Mbps 20MHz DL: 4x4 UL: 1x2 64QAM DL: 300Mbps UL: 75Mbps 100MHz DL: 8x8 UL: 4x4 64QAM DL: 3Gbps UL: 1.5Gbps TM 21

22 3G - UMTS How is it Performance Network Throughput DL/UL balance Latency Hierarchical 300Mbps on DL and 75Mbps on UL 4:1 2 sec on first connection 50ms afterwards Slow, expensive We need much more than that Very unbalanced not suitable for Interactive video, advanced gaming and other video services Way too slow! Possible improvement Shift to flat network (all IP) More bandwidth Better technologies Enhance technology over UL Shift to flat network (all IP) TM 22

23 Small cells is an emerging market Mini base stations covering smaller range Two scenarios Extended coverage Capacity offload Cell type Capacity Coverage Mobility Macro > 256 users Wide coverage High Metro users Outdoor Medium Pico 32 users Enterprise Low Femto 8 users Domestic/Office Low TM 23

24 Users at cell edge experience smaller throughput or sub-par QoS Femtocells at coverage holes TM 24

25 - Offload capacity from the main base station - Separate backhaul TM 25

26 WiFi hot-spots + 4G femto WiFi We already have small cells in our homes They have issues related to coverage Require many small cells Large costs Limited capacity 4G femto Boosts up coverage Deals with more users A lot of business cases relying on the answer TM 26

27 Lecture 2 More insight on radio interface and L1 FDD/TDD OFDMA SC-FDMA Frame formats MIMO We will do some math and derive max peak rate We will fantasize about what could come next Towards 5G TM 27

28 TM