Table of Contents B4G and Beyond Full Dimension MIMO Licensed Assisted Access Next Generation Carrier Aggregation Enhanced Machine Type Communications Other Technologies 5 th Generation Cellular Systems 2
B4G and Beyond 3
3 rd Generation Partnership Project Initiated in December, 1998 for development of wireless communication standards backward compatible backward compatible Rel-99 Rel-5 Rel-6 Rel-8/Rel-9 Rel-10/Rel-11 W-CDMA (1999) HSDPA (2002) HSUPA (2005) LTE (2008) LTE-A (2010) Rel-12 Rel-13 B4G (2014) B4G (2016)? CDMA, QPSK DL: 16QAM AMC, HARQ UL: AMC, HARQ DL: OFDMA, MIMO UL: SC-FDMA CoMP, CA, eicic UL: MIMO Small cells, TDD-FDD CA FD-MIMO, LAA, emtc Collaboration between groups of telecommunications associations China: CCSA (China Communications Standards Association) Europe: ETSI (European Telecommunications Standards Institute) Japan: ARIB (Association of Radio Industries and Businesses), TTC (Telecommunication Technology Committee) Korea: TTA (Telecommunications Technology Association) USA: ATIS (Alliance for Telecommunications Industry Solutions) India: TSDSI (Telecommunications Standards Development Society of India) Specification work done in Technical Specification Groups GERAN (GSM/EDGE Radio Access Network): GERAN specifies GSM radio technology, including GPRS and EDGE RAN (Radio Access Network): RAN specifies the UTRAN and the E-UTRAN SA (Service and System Aspects): SA specifies service requirements and overall architecture of 3GPP system CT (Core Network and Terminals): CT specifies the core network and terminal parts of 3GPP 4
Industry Participation in 3GPP Over 100 companies involved in LTE specification development Mobile Vendors: Samsung, Nokia, Blackberry, LGE, ZTE, Pantech, Motorola, HTC, Apple, System Vendors: Ericsson, Huawei, Alcatel Lucent, Nokia Siemens Network, Chipset Vendors: Qualcomm, Intel, MediaTek, Broadcom, NVIDIA, Service Operators: CMCC, Vodafone, Orange, Verizon, AT&T, KDDI, Sprint, Deutsche Telekom, Korea Telecom, SK Telecom, NTT DOCOMO, Telecom Italia, Softbank, Measurement Instrument Vendors: Agilent Technology, NI, Rohde & Schwarz, Terminal Location Providers: TruePosition, Polaris Wireless,.. Research Firms: InterDigital, ETRI, ITRI, III, 5
LTE Roadmap LTE Rel-8: First release of LTE specification (developed in 2008) LTE-A Rel-10/Rel-11: LTE with 4G capabilities (developed in 2010/2012) LTE-A Rel-12/Rel-13: LTE with Beyond 4G capabilities 2014 2015 2016 2017 2018 2019 1H 2H 1H 2H 1H 2H 1H 2H 1H 2H 1H 2H 2014.12 2015.3 Rel-12 Stage 3 ASN.1 Start of deployment Rel-13 2015.12 Stage 3 Start of deployment 2017.06 Rel-14 Rel-15 Stage 3 Start of deployment 2018.12 Stage 3 6
LTE Release 8: First LTE Specification OFDMA / SC-FDMA: 1.4MHz 20MHz Flat RAN architecture 10ms radio frame, Tf Key technologies Subframe #0 1msec #1 #2 #3 #4 #5 #6 #7 #8 #9 Slot, Tslot 0.5 msec Resource Block (RB) l=0 l=nsymb DL -1 Symbol k = n PRB *N SC RB Subcarrier 15kHz Resource element (k,l) 4x4 DL MIMO Requirements Peak transmission rate (Mbps) Peak spectral efficiency (bps/hz) Average cell spectral efficiency (bps/hz/cell) Cell edge spectral efficiency (bps/hz/user) Target >100 (DL), >50 (UL) >5 (DL), >2.5 (UL) >1.6 2.1 (DL), >0.66 1.0 (UL) >0.04 0.06 (DL), >0.02 0.03 (UL) User plane latency / Control plane latency (ms) < 10 / <100 7
LTE-Release 10: LTE Advanced (LTE-A) Carrier Aggregation Time-domain Inter-cell Interference Coordination Key technologies Cell range expansion Almost Blank Subframe 4x4 UL MIMO 8x8 DL MIMO Requirement Peak transmission rate (Mbps) Peak spectral efficiency (bps/hz) Average cell spectral efficiency (bps/hz/cell) Cell edge spectral efficiency (bps/hz/user) Target 1000 (DL), 500 (UL) 30 (DL), 15 (UL) 2.4 3.7 (DL), 1.2 2.0 (UL) 0.07 0.12 (DL), 0.04 0.07 (UL) 8
LTE-Release 11: Network Coordination Key Technology: CoMP (Coordinated Multi-Point Transmission and Reception) Allows network to coordinate wireless resources (time, frequency, transmission power, etc) Significant improvement in system performance (Average: 20~30%, Edge: 30~40%) Well suited for C-RAN (Centralized Radio Access Network) 9
Small Cell Enhancements Dual Connectivity: Inter-eNB CA Discovery 10
TDD-FDD Carrier Aggregation Carrier Aggregation Utilization of multiple LTE carriers to increase UE throughput and peak rate Key feature of LTE-A currently supported in the latest LTE terminals and networks TDD-FDD Joint Operation A terminal will have support for both TDD and FDD carriers A network can assign both TDD and FDD carriers to a terminal simultaneously or separately Why is it important? Market demand: Operators with both TDD and FDD carriers (via merger, refarming, etc) Benefits of both TDD and FDD systems Flexible load balancing between TDD and FDD carriers 11
eimta (Enhanced Interference Mitigation and Traffic Adaptation) Hotspot area 1: change UL resource to DL resource D S U U U D S U U U dynamically over time, also between nodes D S U D D D S U D D Time-Division Duplex Key benefit: Ratio of uplink and downlink resources can be configured Key limitation: Ratio of uplink and downlink resources cannot be configured dynamically eimta (Enhanced Interference Management and Traffic Adaptation) Provide mechanisms to allow dynamic switching between uplink and downlink resources Allows network to adapt resources considering uplink and downlink traffic 12
Machine Type Communications Current mobile networks were designed for humans (i.e. human-human or human-machine) Internet access, telephony, multi-media downloading or streaming, SMS/MMS Mobile devices that we are used to: Mobile devices that we might not be aware of: Machine Type Communications: Communication between machines Quality of service, quality of experience as not important (devices do not complain) Data rate is less important compared to coverage (devices do not have ability to move at will) Modem cost is very important ($30 modem on $1000 smart phone is okay but not on $50 meter) 13
Device-to-Device (D2D) Communications Peer discovery UE discovers other UEs proximate to itself Mainly for commercial use case Direct communication UE transmits data to other UE(s) with network assistance inside network coverage Broadcast communication is studied in Rel-12 Out of network coverage D2D communication should also be supported in out of network coverage Key feature for public safety use case 14
LTE/LTE-A Evolutions Efficient Frequency Usage Carrier Aggregation (Rel-10) Carrier Aggregation Enhancement (Rel-11) TDD-FDD Joint Operation (Rel-12) Dual Connectivity (Rel-12) Licensed Assisted Access (Rel-13) Carrier Aggregation Beyond 5 Carriers (Rel-13) Higher Spectral Efficiency Downlink MIMO (Rel-8) Downlink MIMO Enhancement (Rel-9, Rel-10) Uplink MIMO (Rel-10) Enhanced Inter-Cell Interference Coordination (Rel-10) Coordinated Multi-Point TX/RX (Rel-11) Network Assisted Interference Cancellation and Suppression (Rel-12) Full Dimension MIMO (Rel-13) Support of New Services Multimedia Broadcast Multicast Service (Rel-9) Voice over LTE (Rel-9) Machine Type Communications (Rel-12) Device-to-Device (Rel-12) Enhanced Machine Type Communications (Rel-13) 15
Full Dimension MIMO 16
Concept of Full Dimension MIMO 3 dimensional beamforming operation with 2D antenna array w Dynamic/flexible vertical or horizontal or 3D sectorization w 3D UE-specific beamforming with high-order multiuser MIMO w Legacy systems only have freedom in horizontal domain Flexible V/H sectorization 3D beamforming Hotspot Vertical sectors SAMSUNG Electronics Co., Ltd. Confidential and 17
Concept of Full Dimension MIMO (2/2) Full Dimension MIMO system: 2D array structure with AAS (Active antenna system) w 2D patch antenna array with PA integration w Flexible port to antenna array mapping (UE specific and/or cell-specific) w Enable 3D (vertical and horizontal) beamforming Legacy system Feed network FD-MIMO system Patch antenna Flexible system 8TX (8Hx1V) Passive antennas Flexible 2D port mapping Baseband+PA CPRIs IP 32TX (8Hx4V) LTE infrastructure FD-MIMO baseband 18
3D Channel Model (1/3) 3D extension of spatial channel model (SCM) w w Long-term channel characteristics of UE height (e.g LOS probability of UE and pathloss) Short-term channel characteristics of vertical domain and UE height (e.g. Zenith angle spread in departure as well as arrival) Long-term channel extension Short-term channel extension subpath 3D Cluster Increase chance of LOS z y 2D Cluster Increase chance of LOS Reduce pathloss (height gain) x 3D antenna pattern z path horizontal plain NLOS y x 19
3D Channel Model (2/3) 3D extension of deployment model w UMa (Urban Macro model): enb antenna is above rooftops (25m from ground) 3D extension of UE dropping model w 80% UE location on 1st ~ 8th floor in indoor buildings w Higher chance of MU-MIMO (ex: center and edge UEs on different floors) 2D UMa 3D UMa 25m 25m 1.5m 1.5m Horizon View at enb antenna 20
3D Channel Model (3/3) 3D extension of deployment model w UMi (Urban Micro model): enb antenna is below rooftops (10m from ground) 3D extension of UE dropping model w 80% UE location on 1st ~ 8th floor in indoor building w For cell center UEs, increased beamforming angle in vertical domain 2D UMi 3D UMi 10m 10m 1.5m 1.5m Horizon View at enb antenna View at enb antenna 21
Potential Specification Impact Enhanced CSI-RS For measurement of large number of antennas in 2-D antenna array panel Enhanced DMRS For providing large number of orthogonal DMRS ports for high order multi-user multiplexing Enhanced CSI (Channel Status Information) For reporting preferred precoding information with accuracy but with low overhead For provisioning accurate link adaptation in the presence of multi-user interference New transmission schemes Open loop, semi-closed loop transmission schemes for lowering CSI overhead 22
Preliminary Performance Evaluation (1/3) Evaluation of FD-MIMO with system level simulation w Based on new channel model: 3D UMa, 3D UMi w Number of antenna ports: 8, 16, 32, 64 ports w Overhead assumption: no overhead Evaluation scenario Scheduling algorithm Parameter Layout Scenario TX power Carrier frequency Bandwidth Number of UEs HARQ scheme Link adaptation CSI feedback Channel estimation Element configuration UE mobility Value 19 cells with 3 sector 3D UMa (ISD:500m), 3D UMi (ISD:200m) 46dBm(3D UMa), 41dBm (3D UMi) 2GHz 10MHz 10 UEs per cell IR asynchronous retransmission LTE MCS selection with 10% BLER Ideal subband Rel.10 SU-CSI Ideal estimation without error 60º for both vertical and horizontal with 6.5dBi 3Km/h with 3D dropping Simple PF scheduling is applied Step1: Select best UE with SU-CSI Step2: Add UE if sum of PF metric is increased with considering MU interference Step3: Recalculate CQI for MU scheduling 23
Preliminary Performance Evaluation (2/3) Results of geometry and UE s zenith angle distribution w w w No significant change on geometry with new 3D UE distribution Slightly better geometry in 3D UMi (due to high LOS probability) than 3D UMa Large zenith angle of interest in 3D UMi (90~120º in 3D UMa, 57~130º in 3D UMi) Geometry distribution Zenith angle distribution CDF [%] 100 90 80 70 60 50 40 30 20 10 3D UMi geometry 3D UMa geometry 0-10.00 0.00 10.00 20.00 30.00 Geometry [db] CDF [%] 100 90 80 70 60 50 40 30 20 10 3D UMa 3D UMi 0 0.00 30.00 60.00 90.00 120.00 150.00 180.00 ZoD [degree] 24
Preliminary Performance Evaluation (3/3) System performance of MU-MIMO w w By increasing number of antennas in V or H domain: Narrower beam provides significant MU gain (1x8)à(1x64): x2.2 in avg, x4 in edge With 2D array structure: Can achieve significant gain with 3D beamforming (1x8)à(8x8): x1.76 in avg, x3.3 in edge Cell throughput Cell vs 5% edge throughput 64 ports 32 ports 1x64 2x32 16 ports 8 ports 4x4 1x32 2x16 4x8 8x4 8x8 4x16 25
PoC Status - Overview (1/4) World s First FD-MIMO system w Indoor/outdoor tests for LTE TDD with 10MHz bandwidth @ 2.582GHz w 128 elements configured as 32Tx/32Rx (subarray of 1x4 elements) 128 elements 32 TX/RX TDD, 2.582GHz Automatic self calibration Size: 50x100cm UE emulators UE emulator#1 Front view FD-MIMO Baseband unit Compliant with LTE air interface 32 channel precoding with sounding 4-UE MU-MIMO FD-MIMO RF unit with antenna panel Back view Indoor test v Outdoor test v v Over-the-air test 2-UE MU-MIMO w/ adaptive beamforming based on SRS Test 1: 2-UE MU-MIMO w/ fixed beamforming Test 2: 2-UE MU-MIMO w/ adaptive beamforming based on SRS 26
PoC Status - Overview (2/4) Indoor PoC test set up w 2-UE MU-MIMO with adaptive BF based on SRS with beam tracking update every 10 ms w Measured receiver SNR: ~44dB SNR @ 64QAM SU-MIMO ~21dB SNR @ 64QAM 2-UE MU-MIMO FD-MIMO RFU FD-MIMO baseband with GPS clock source 16⁰ azimuth 6⁰ elevation beam width UE emulator 2 UE emulator 1 8dBi UE1 antenna 8dBi UE2 antenna ~0.6% EVM @ 64QAM UE monitors 27
PoC Status Outdoor Field Test#1 (3/4) Outdoor PoC test #1 (fixed beamforming) w Purpose was to compare single UE SU-MIMO and 2-UE MU-MIMO w UEs were located 100m away from FD-MIMO antenna w Compared to SU-MIMO, 2-UE MU-MIMO achieved ~1.8x capacity SNR Code rate Throughput Cell capacity Reference: 1 UE SU 38dB 0.95 37.8Mbps 37.8Mbps RFU setup FD-MIMO UE#1 19dB 0.9 35.4Mbps FD-MIMO UE#2 19dB 0.85 33.5Mbps 68.9Mbsp UE setup MU-MIMO test locations 28
PoC Status Outdoor Field Test#2 (4/4) Outdoor PoC test #2 (adaptive beamforming based on SRS) w Azimuth/elevation beam-tracking test for 1-UE SU-MIMO and 2-UE MU-MIMO Beam tracking consistently performs well with narrow beams (6º/12º in V/H 3dB) w Single user case: SNR 26~34dB with 2~5% EVM w MU-MIMO case: SNR 16~21dB with 8~15% EVM Route 1 MU UE1 UE2 UE#1 Route#2 Route#1 32-ch TRX 128-element antenna enb enb height (~10m) UE#2 Route#0 29
Licensed Assisted Access 30
Licensed vs Unlicensed Band Licensed Band License typically requires a fee (a big one) Operator retains exclusive rights for use For macro coverage with cell planning Unlicensed Band No license and therefore no fee (free) Anyone can use For local coverage with limited planning High transmission power (ex. 46dBm) Suitable for providing large coverage Low transmission power (ex. 23dBm) Coverage is limited A frequency resource is used by single radio access technology (ex. LTE, WCDMA) A frequency resource is used by multiple radio access technologies (ex. Bluetooth, WiFi) Communication based on resource allocation, link adaptation, HARQ, scheduling, interference control QoS can be guaranteed Communication based on collision avoidance QoS cannot be guaranteed 31
Licensed vs Unlicensed Band Licensed band is preferable for providing consistent user experience The amount of available licensed spectrum is limited and costly Radio technologies: LTE, W-CDMA, cdma2000, HRPD, GSM, IS-95, etc Unlicensed band is preferable for providing inexpensive wireless services Significant amount of unlicensed spectrum in 2.4GHz and 5GHz for free Radio technologies: Bluetooth, wireless phones, IEEE 802.11a/b/g/n/ac, etc What if technologies for licensed spectrum can be used on unlicensed spectrum? LTE on unlicensed band (LTE-U or LAA) 32
Unlicensed Spectrum Two main unlicensed spectrum bands in use globally: 2.4GHz: Extensively used for Bluetooth, WiFi (IEEE 802.11b), wireless phones 5GHz: Relatively new and used mainly for WiFi (IEEE 802.11a/n/ac) Up to 500MHz available 5GHz unlicensed spectrum Depends on regional regulations Additional WiFi spectrum under consideration to be discussed and decided after WRC-15 (5350MHz~5470MHz and 5825MHz~5925MHz) 33
Licensed Assisted Access (LAA) Concept Conventional LTE/LTE-A: Data and control signaling on licensed carrier Data Licensed f Data Licensed f Control Licensed f WiFi: Data and control signaling on unlicensed carrier Data Data Control Unlicensed f Unlicensed f Unlicensed f LAA: Data on licensed and unlicensed carrier but control on licensed carrier only Data Licensed f Data UnLicensed f Control Licensed f Licensed Assisted 34
LAA Operation Source: Qualcomm Basic operation relies on LTE-A carrier aggregation mechanism Two LTE carriers are utilized for a single LAA terminal One LTE carrier on licensed band à Mobility support, reliable data/control pipe One LTE carrier on unlicensed band à Data fat pipe 35
LAA Network Architecture Source: Huawei Existing core network is reused Unified authentication and security management, OSS and radio resource management No need for two separate networks (i.e. one for LTE/LTE-A and another for LTE-U) All network functionality enhancements are on the enb side Only enb upgrade is necessary 36
Benefits of LAA Extending the benefits of LTE/LTE-A to unlicensed spectrum Enhanced User Experience Unified LTE Network Cellular mechanism over unlicensed band (coverage, mobility, QoS control) Same core elements Improved spectral efficiency vs WiFi (link adaptation, HARQ, interference management) Same mobility and security framework Despite benefits, LAA deployment depends on coexistence with pre-existing networks 37
WiFi Deployment Status in Korea Korea s three operators have heavily invested in deployment of WiFi APs Example: Korea Telecom has close to 100,000 WiFi zones in operation (ref: http://zone.wifi.olleh.com/index.action) Large portion of commercial APs operate on 5GHz using IEEE 802.11n Since 2013, commercial IEEE 802.11ac APs have been deployed throughout Korea All latest flagship smart phones have 802.11ac capability <Wi-Fi Deployment Korea, August 2012> AP Types KT SKT LGU+ Total Wi-Fi Zones (APs Deployed) 99,000 (174,000) 73,000 (102,000) 19,000 (82,000) 191,000 (358,000) Coffee shops, residential 1.58 million 0.34 million 1.93 million 3.85 million Total 1.75 million 0.44 million 2.01 million 4.21 million 38
LAA and Coexistence Requirements on Unlicensed Band Listen Before Talk (LBT) Before transmitting, terminal scans for channel usage by other terminals Transmit power control (TPC) Used to ensure a mitigation factor of at least 3 db on the aggregate power from a large number of devices Dynamic frequency selection (DFS) Upon detection of radar activity, terminal reallocates to another channel Regulation on unlicensed band differs by region US: No LBT requirement, Europe/Japan: LBT requirement enforced Even for regions without LBT, coexistence of WiFi and LTE is very important LTE is designed for harsh interference environments WiFi is designed to avoid collisions à to protect itself and to protect other terminals Support of coexistence mechanism for is the most important part LAA standardization in Rel-13 Without a coexistence mechanism, WiFi performance could be degraded 39
LAA Deployment Scenarios 40
LAA Evaluation Results LAA-WiFi coexistence performance Baseline: performance of Wi-Fi network (Operator 1) coexisting with Wi-Fi network (Operator 2) Target: performance of Wi-Fi network (Operator 2) coexisting with LAA network (Operator 1) Case 1: LBE-based LAA with 4ms and 10ms maximum channel occupancy time Case 2: FBE-based LAA with 5ms and 10ms fixed frame duration * Evaluation assumptions - Indoor scenario - 4 AP/eNBs per operator - 40 UE per operator - 4 channel for both operators - High load condition (72% buffer occupancy) 41
Next Generation Carrier Aggregation (Carrier Aggregation Beyond 5 Carriers) 42
Carrier Aggregation Beyond 32 CCs Carrier aggregation history Rel-10: Introduction of CA (up to 5 carriers, 100MHz) Rel-11: TDD CA enhancement (flexible UL/DL ratios) Rel-12: TDD-FDD CA, dual connectivity (inter-enb CA) Rel-13: CA beyond 32 CCs Carrier aggregation (CA) is the most successful LTE-A feature Every year, CA capability in terminals are enhanced à 4CC CA coming soon In order to fully utilize unlicensed band, next generation CA is necessary Up to 32 component carriers: up to 640MHz and 25.6Gbps 43
Key Specification Support PUCCH on Scell PUCCH on Scell - In Rel-12, PUCCH on Scell was introduced to support dual connectivity between inter-enb CA with non-ideal backhaul - For Rel-13, PUCCH on Scell will be specified to support intra-enb CA with ideal backhaul PCell PUCCH Ideal backhaul PUCCH SCell CA of up to 32 CCs CA of up to 32 CCs - Until Rel-12, CA with only 5 CCs was supported Licensed band Unlicensed band 1 2 3 4 5 6 32 - For Rel-13, CA of up to 32 CCs will be specified with necessary enhancements in DL/UL control channels 44
Enhanced Machine Type Communications 45
Rel-12 Low Cost & Enhanced Coverage MTC (1/2) 3GPP work schedule: 2013.6 ~ 2014.12 Rapporteur: Vodafone Key objectives 1 Rx antenna Reduced maximum Transport Block Size (TBS) (downlink/uplink) Reduced channel bandwidth (BW) Reduced downlink channel bandwidth of 1.4 MHz for data channel in baseband (à eventually, no bandwidth reduction is specified in Rel-12) The control channels are still allowed to use the carrier bandwidth Uplink channel BW and BW for uplink and downlink RF remains the same as that of normal LTE UE * The scope was reduced by removing coverage improvement aspects ( à deferred to Rel-13) 1 Rx antenna à cost reduction in terms of Rx filter, FFT process, channel estimator, ADC, post-fft data buffer, etc. Reduced Max TBS à cost reduction in terms of soft buffer, decoding process, etc. 46
Rel-12 Low Cost & Enhanced Coverage MTC (2/2) Rel-12 specification details 1 Rx antenna (à New RAN4 requirements) New UE category (Category 0) <Downlink> UE Category Max spatial layer for downlink and uplink: 1 No 64 QAM in uplink Max TBS size is reduced 1000 bits for unicast traffic For broadcast traffic, 2216 bits (à to support current SIB) No restriction on the number of PRBs for broadcast traffic (à i.e. no cost saving in terms of PRB) For unicast traffic, the number of PRBs is restricted by Max 1000-bit TBS Total number of soft channel bits: 25344 bits Maximum number of DL-SCH transport block bits received within a TTI (Note 1) Maximum number of bits of a DL-SCH transport block received within a TTI Total number of soft channel bits Category 0 1000 1000 25344 1 <Uplink> Maximum number of supported layers for spatial multiplexing in DL UE Category Maximum number of UL-SCH transport Maximum number of bits of an UL-SCH Support for 64QAM in UL block bits transmitted within a TTI transport block transmitted within a TTI Category 0 1000 1000 No Half-duplex FDD operation Rx-to-Tx guard period: UE not receiving the downlink subframe immediately preceding an uplink subframe Tx-to-Rx guard period: UE not receiving the downlink subframe immediately following an uplink subframe 47
Rel-13 Further LTE PHY Layer Enhancements for MTC 3GPP work schedule: 2014.9 ~2015.12 Rapporteur: Ericsson Key objectives UE Cost reduction (e.g. 1.4MHz narrowband operation) Coverage enhancement (15 db improvement) UE Power Consumption reduction Expected benefits New revenue generation for operators by means of boosting LTE based MTC UE Enable cellular IoT 48
Rel-13 Further LTE PHY Layer Enhancements for MTC Rel-13 candidate solutions Low complexity Reduced UE bandwidth of 1.4 MHz in downlink and uplink Reduced maximum transmit power Reduced support for downlink transmission modes UE processing relaxations (e.g. reduced number of HARQ process, reduced CSI reporting mode, etc.) Coverage improvement Subframe bundling Elimination or repetition of control channel Cross-subframe scheduling Power consumption reduction Reduced active transmit/receive time Reduction of measurement time/reporting, feedback signalling, etc Cost reduction estimation (RP-141180) Feature Cat-4 Cat-1 Rel-12 Low Rel-13 Low Complexity UE Complexity UE UE RF Bandwidth 20 MHz 20 MHz 20 MHz 1.4 MHz DL Peak Rate 150 Mbps 10 Mbps 1 Mbps ~200 kbps Max No of DL Layers 2 1 1 1 UL Peak Rate 50 Mbps 5 Mbps 1 Mbps ~200 kbps No of RF Rx chains 2 2 1 1 Max UE Tx power 23 dbm 23 dbm 23 dbm ~20 dbm Duplex Mode Full Full Half (optional) Half (optional) Relative BOM Cost 125% 100% 50% 20-25% 49
Enhanced Device to Device Communications Rel-12 D2D satisfies basic requirements of public safety. Some requirements are still unsatisfied, e.g., unicast, relay functionalities, etc. Public safety community may try to enhance D2D in Rel-13. Rel-12 D2D D2D communication is based on broadcast. Unicast and groupcast are supported by broadcast D2D communication Discovery is supported only inside the network coverage Relay is not supported Potential D2D enhancements in Rel-13 Enhanced D2D unicast communication by introducing feedback scheme. AMC and HARQ can be supported for D2D communication Support of NW to UE relay and/or UE to UE relay Discovery for out of network coverage 50
Enhanced NAICS Rel-12 NAICS focuses on SL-IC/R-ML receivers for PDSCH IS/IC of without tight network coordination IS/IC for up to 2 CRS ports and up to 2 DMRS ports enaics could consider MU-scenarios, more CRS/DMRS ports, or other receiver types Rel-12 NAICS specification supports Inter-TP interference scenario without tight inter-tp coordination and scheduling restriction Network assistance by higher-layer signalling (subset of interference parameters) Large part of NAICS relies on blind detection Feasibility was proved only for up to 2 CRS ports and up to 2 DMRS ports Still FFS for CRS TMs in case of 4 CRS ports Potential NAICS enhancements in Rel-13 Network assistance for dynamic interference parameters In MU-MIMO scenarios or tight network coordination scenarios Support for CRS TMs in case of 4 CRS ports Support for larger than 2 DMRS ports IS/IC for PDCCH or epdcch Study on further advanced receivers, e.g. CWIC or Iterative ML 51
Indoor CoMP Rel-11 CoMP considers coordination between up to 3 TPs assuming ideal backhaul Rel-12 ecomp focuses on inter-enb coordination assuming non-ideal backhaul Proposal for Rel-13 is to expand and focus on indoor scenarios (many interfering nodes) Rel-11 CoMP specification supports: Feedback enhancement and L1 signaling enhancement for CoMP (CS/CB, DPS and JT) Coordination between up to three TPs Up to three CSI-RS/CSI-IM resources for channel/interference measurement Rel-12 ecomp specification supports: Inter-eNB coordinated scheduling assuming non-ideal backhaul L3 signalling enhancement to support tight coordination between enbs Potential further enhancement of CoMP in Rel-13 (from Ericsson): Main scenario would be indoor office environment with many interfering nodes To support coordination between in indoor environment Enhancements to reduce IMR overhead Enhancements to CSI feedback for larger number of nodes Indoor nodes interfering with each other source: Ericsson 52
Flexible Duplex (1/2): Motivations Downlink and uplink traffic volume is expected to become more asymmetric w Due to larger dominance of video traffic (DL:UL>20:1) in mobile data FDD s equally divided downlink/uplink doesn t fit well with realistic traffic situations w On the other hand, TDD is able to control the ratio of DL/UL (UL/DL configurations, eimta) Mobile data traffic share by application type (Source: Ericsson Mobility Report, 2013) 2012 2018 Video Video The asymmetric nature of downlink and uplink traffic in reality Downlink is heavier in most cases (ex: for video streaming, UL is less than 5% of DL) However, depending on location, time, and application type, uplink could account for a large portion (ex: social networking) 53
Flexible Duplex (2/2): Further Discussions Considering the current limitations of FDD in terms of traffic adaptation, flexible duplex could be one of the enhancements for consideration in Rel-13 w eimta-link specification support for FDD Consider different duplex directions on the same band of a FDD cell Uplink frequency can be used for both uplink and downlink transmission to cope with asymmetric uplink and downlink traffic ratio Consider transmitting uplink SRS transmissions on downlink frequency to allow FDD systems to utilize channel reciprocity for downlink MIMO Consider eimta-like specification support for FDD Configuration of UL/DL subframes on the two bands switched in a small time scale 54
5 th Generation Cellular Systems 55
5G Vision Network architecture design is expected to be evolved in the 5G era to enable flexible deployment and smart operation. EMS*/NMS* Service Mgmt. Optimization of network-control related parameters Platform Management Plane VNF* migration VNF scale in/out or scale up/down SON Analytics Big Data PM* data from Network Utilization to industries for the business insight Data from CRM*, SNS* etc. *CRM: Customer Relationship Management *SNS: Social Network Service *PM: Performance Management Access Network Core Network VNF (e.g. SGW/PGW/MME, Cache, Local contents ) Probe NFV platform (Server/Storage) 56
7 Key Requirements for 5G Peak Data Rate [Gbps] Latency [msec] IMT-2020 Cell Edge Data Rate [Mbps] IMT-Adv Simultaneous Connection [10 4 /km 2 ] Cell Spectral Efficiency [bps/hz] Cost Efficiency [Bit/$] Mobility [km/h] 57
Ultra Fast Data Transmission Peak Data Rate Order of Magnitude Improvement in Peak Data Rate 50 Gbps Data Rate Peak Data Rate > 50 Gbps More than x50 over 4G 50 Gbps [1] 6 Gbps [2] 1 Gbps 1 Gbps [1] 75 14 Mbps [1] Mbps[2] 384 kbps [2] 00 07 10 20 Year [1] Theoretical Peak Data Rate [2] Data Rate of First Commercial Products 58
Ultra Fast Data Transmission Uniform Experience of Gbps Speed and Instantaneous Response Latency Cell Edge Data Rate 1 Gbps Anywhere E2E Latency < 5 msec QoE BS Location 5 ms 50 ms A Tenth of E2E Latency E2E Latency Cell Edge QoE BS Location Uniform Experience Regardless of User-location 10 ms 1 ms Air Latency < 1 msec A Tenth of Air Latency Air Latency 59
Spectrum Candidates Candidates for Large Chunks of Contiguous Spectrum w 13.4~14 GHz, 18.1~18.6 GHz, 27~29.5 GHz, 38~39.5 GHz, etc Higher Frequency Candidates ITU EESS FSS RL MS FS FSS MS FS FSS MS FS FSS 27.5 29.5 31.3 33.8 38.6 40 41 42.5 26.5 29.5 31.3 33.4 40.2 42.5 13.4 14 18.1 18.6 27 29.5 38 39.5 Current Usage US: LMDS, FSS EU: Fixed P-P link, FSS earth sta. China: Mobile, FSS Korea : Maritime use Current Usage US: Fixed P-P system EU: Fixed P-P link Korea : None MOBILE Primary No MOBILE EESS (Earth Exploration-Satellite Service) FSS (Fixed Satellite Service) RL (RadioLocation service), MS (Mobile Service) FS (Fixed Service) P-P (Point to Point) LMDS (Local Multipoint Distribution Services) 60
mmwave Propagation : Modern Office Electric Field Measurements in Typical Office Environments w High data rate support is possible with proper deployment of low power BSs Electric field measurements Measurements at 148 Rx locations ü Tx: 2 beams with HPBW 30 each, Rx: Dipole antenna Possible to provide coverage over whole office with 2 BSs ü SNR is expected to be above 5 db (BS Power 23 dbm, 500MHz BW) ü Min. 500 Mbps can be supported (Noise Figure 5dB) Office pathloss model Pathloss model from ref. location ü Reference : 3m distance LoS ü Measured location: 4m ~ 63m LoS/NLoS Exponent 2.1 is observed by regression Pathloss [db] Distance [m] 61
Channel Measurement Indoor Extensive channel measurements have been conducted and ongoing in Korea w Horn-Ant. based channel sounder with Tx-Rx Sync. has been developed w Omni-directional channel modeling of small scale parameters underway (e.g. Clustering, AoA/AoD) Channel sounder and structure map Measurements at Total 16 Rx Locations ü Tx-Rx Distance : 10m ~ 40m ü Max. RMS delay spread : 83.7 [ns] at location 13 Tx-Rx Channel Sounder Perspective from the 3 rd FL Tx Location 9 6 2 1 10 3 16 4 15 Exemplary Channel Parameter Modeling (location 1) ü Clustering ü AoA/AoD power distribution [ KAIST KI Bldg., Korea ] Excess Delay [ns] AoD [deg.] AoA [deg.] Power [db] Power [db] AoA [deg.] AoD [deg.] 62
Channel Measurement Outdoor Similar path-loss exponent & smaller delay spread measured (w.r.t. current cellular bands) w Measurements were made by using horn-type antennas at 28 GHz and 38 GHz in 2011 Samsung Campus, Korea UT Austin Campus, US LOS NLOS Path Loss Exponent 2.22 3.69 RMS Median 4.0 34.2 Delay Spread [ns] 99% 11.4 168.7 LOS NLOS Path Loss Exponent 2.21 3.18 RMS Median 1.9 15.5 Delay Spread [ns] 99% 13.7 166 Tx (10 o ) Rx (60 o ) 28 GHz University of Texas at Austin, TX Tx (7.8 o ) 37.6 GHz Rx (49 o ) Received power [dbm] 0-10 -20-30 -40-50 [Received Power] Received power for 10->60 LOS n=2.22, s=4.18db NLOS-best n=3.69, s=3.58db NLOS-all n=4.20, s=7.38db [Received Power] -60-70 5 10 1 10 2 Distance [m] * Reference : Prof. Ted Rappaport, UT Austin, 2011 63
Channel Measurement Dense Urban Slightly higher but comparable path loss measured in New York City in 2012 Manhattan, New York, US Reference : Prof. Ted Rappaport, NYU, 2012 - T. S. Rappaport et.al. Millimeter Wave Mobile Communications for 5G Cellular: It Will Work!, IEEE Access Journal, May 2013 LOS NLOS Path Loss Exponent 1.68 4.58 Delay Spread [ns] Expected to be larger than the previous, But to be still smaller than current bands Tx (10 o ) Rx (10 o ) 28GHz [New York, Manhattan NY University] [Path Loss] 64
mmwave Beamforming Prototype World s first mmwave mobile technology w Adaptive array transceiver operating in the mmwave frequency bands for outdoor environment 25 mm 42 mm 45 mm 5 mm 65
Test Results Range Outdoor Line-of-Sight (LoS) range test w Error-free communications possible at 1.7 km LoS with > 10dB Tx power headroom w Pencil beamforming at both TX/RX supporting long range communications LoS range Support wide-range LoS coverage Suwon Campus, Korea Base - 1710m LOS 측정 자료로 Station 수정 예정 ü 16-QAM (528Mbps) : BLER 10-6 ü QPSK (264Mbps) : Error Free 1.7 km Mobile Station 66
Test Results Coverage Outdoor Non Line-of-Sight (NLoS) coverage tests w Block error rate less than 0.01% up to NLoS 200m distance Wonil Roh, et al., Millimeter-Wave Beamforming as an Enabling Technology for 5G Cellular Communications: Theoretical Feasibility and Prototype Results, IEEE Communications Magazine, Feb. 2014. 67
Test Results Mobility Outdoor-to-indoor penetration tests w Most signals successfully received by indoor MS from outdoor BS Wonil Roh, et al., Millimeter-Wave Beamforming as an Enabling Technology for 5G Cellular Communications: Theoretical Feasibility and Prototype Results, IEEE Communications Magazine, Feb. 2014. 68
Test Results Multi-User Support Multi-User MIMO tests w 2.48 Gbps aggregate throughput in MU-MIMO mode Carrier Frequency 27.925 GHz Bandwidth 800 MHz Max. Tx Power 37 dbm Beam-width (Half Power) 10 o Channel Coding LDPC MIMO Configuration 2 x 2 BS RFU MS RFU 1 MS RFU 2 BS Modem 1.24Gbps 1.24Gbps MS Modem 1 MS Modem 2 69
Simulation Analysis Beamforming compensate the effects of chassis/hand/head w Lower power penetration through skin at higher frequencies Chassis / Hand-Held Effect Bare PCB Package Head Effect Power Absorption of 1.9 GHz Omni-Antenna w/o head w/ head Broadside Beamforming Endfire Beamforming Penetration depth = 40~45 mm, Average = 0.29, MAX = 1 mw/g Power Absorption of 28 GHz Beamforming Array 1 1 1 2 2 2 1 Penetration depth = 3 mm, Average = 0.15, MAX = 90 mw/g 2 Penetration depth = 3 mm, Average = 0.016, MAX = 2.11 mw/g 70
Antenna Implementation 32 elements implemented on mobile device with zero area and 360 o coverage Zero Area Design Measurement Results 16 Element Array < 0.2 mm Negligible Area for Antennas on Edges 16 Element Array 71
5G Deployment Scenarios Bird s eye view of Chicago 72
5G Deployment Scenarios Bird s eye view of Chicago 4G base stations 73
5G Deployment Scenarios 5G Deployment Scenarios 5G small cells overlayed on existing 4G network w Reduced CAPEX/OPEX for initial deployment 5G small cells 74
5G Deployment Scenarios 5G standalone system w Full capability standalone 5G systems will provide coverage for the entire city 5G macro/pico cells 5G macro/pico cells 75
Conclusions 76
Concluding Remarks Wireless standards have evolved throughout the years 1G (AMPS) à 2G (GSM, IS-95) à 3G (W-CDMA, cdma2000) à 4G (LTE, Wibro) à 5G (?) With each generation came new features and capabilities 1G à 2G (1990 s): Analog à Digital (10kbps) 2G à 3G (~2000): higher than 200kbps, CDMA 3G à 4G (~2010): higher than 1Gbps, OFDMA, MIMO 4G à B4G (~2015): FD-MIMO, small cell enhancement, D2D B4G à 5G:? B4G and 5G evolution will bring in yet another set of features To allow more efficient frequency usage To achieve higher spectral efficiency To handle new and different services 77