Successfully reported this slideshow.
We use your LinkedIn profile and activity data to personalize ads and to show you more relevant ads. You can change your ad preferences anytime.

Prof. Andy Sutton: 5G RAN Architecture Evolution - Jan 2019

5,274 views

Published on

This presentation explores the evolution of GSM, UMTS and LTE radio access network architectures before a detailed review of the RAN architecture options for 5G. The functional decomposition of the 5G radio access network presents the network designer with many challenges with regards placement of RU, DU and CU nodes, all of which are discussed. The presentation concludes with a review of BT UK plans for 5G launch with a fully distributed RAN in support of an EN-DC architecture.

Presented by Professor Andy Sutton CEng FIET, Principal Network Architect, Architecture & Strategy, BT Technology at IET 5G - the Advent conference on 30 January 2019 | IET London: Savoy Place

*** SHARED WITH PERMISSION ***

Published in: Technology
  • Be the first to comment

Prof. Andy Sutton: 5G RAN Architecture Evolution - Jan 2019

  1. 1. British Telecommunications plc 2018 5G Radio Access Network Architecture Evolution Professor Andy Sutton CEng FIET Principal Network Architect Architecture & Strategy BT Technology 30th January 2019
  2. 2. British Telecommunications plc 2018 Contents • Lessons from the past - GSM, UMTS and LTE • 5G RAN architecture evolution • RAN functional decomposition • Access network connectivity • 5G network deployment • 5G demo update • Summary 2
  3. 3. British Telecommunications plc 2018 GSM - fully distributed RAN • GSM BTS is a fully distributed radio base station • All radio related protocols terminate in the BTS • Radio interface encryption terminates in the BTS • Distributed intelligence with centralised BSC 3 BTS Abis interface BSC Nokia GSM Ultrasite BTS Core network NOTE: IP Sec GW used between BTS and BSC with IP Abis implementation
  4. 4. British Telecommunications plc 2018 UMTS - many centralised functions • UMTS is a simple L2 radio base station (known as Node B) • All radio related protocols terminate in the RNC • Radio interface encryption terminates in the RNC • Distributed radio with centralised intelligence 4 NodeB Iub interface RNC Nokia UMTS Ultrasite BTS Core network
  5. 5. British Telecommunications plc 2018 LTE - distribution wins again… • LTE eNB is a fully distributed radio base station • All radio related protocols terminate in the eNB • Radio interface encryption terminates in the eNB • X2 interface between adjacent eNBs, no centralised network controller 5 eNB S1 interface EPC Huawei 3900 eNB (+GSM BTS) eNB S1 interface SecGW Core network 2600 MHz RRU
  6. 6. British Telecommunications plc 2018 LTE - RAN options • LTE eNB is a fully distributed radio base station • However, this radio (eNB) is made up of two components which can be geographically separated • RRU/RRH and BBU - separated by CPRI interface 6 RRU CPRI BBU Huawei 3900 eNB (+GSM BTS) RRU CPRI BBU S1 interface 2600 MHz RRU S1 interface
  7. 7. British Telecommunications plc 2018 Base station architecture - LTE 7 RRU BBU RRU S1 interface BBU S1 interface RRU BBU S1 interface CPRI CPRI D-RAN with cabinet RFU D-RAN with external RRU C-RAN with centralised BBU Note: a site may support one or more base station architectures for different radio channels/bands
  8. 8. British Telecommunications plc 2018 RAN functional splits - protocol architecture 8 RRC PDCP Data Low- RLC High- MAC High- PHY Low- MAC Low- PHY RF High- RLC RRC PDCP Data Low- RLC High- MAC High- PHY Low- MAC Low- PHY RF High- RLC Option 1 Option 2 Option 3 Option 4 Option 5 Option 6 Option 7 Option 8 Relaxed Very low End to end latency Traffic/capacity related Very high Capacity requirement Higher layer splits Lower layer splits S 1 CPRI Reference 3GPP TR 38.801
  9. 9. British Telecommunications plc 2018 RAN functional decomposition 9 gNB RU* DU CU * RU could be integrated within AAU (mMIMO) or standalone RU (RRU/RRH) with coaxial connections to passive antenna (typically 8T8R) CPRI eCPRI F1 interface S1 interface (EPC+) N2/N3 interfaces (NGC) NR (air) interface
  10. 10. British Telecommunications plc 2018 RAN functional decomposition - E1 interface 10 gNB RU* DU CU-c * RU could be integrated within AAU (mMIMO) or standalone RU (RRU/RRH) with coaxial connections to passive antenna (typically 8T8R) CPRI eCPRI F1-c NR (air) interface CU-u F1-u N2 N3 E1 Additional work is on-going on: • DU-CU split for LTE (W1 interface) • E2 interface between CU and RAN Intelligent Controller (RIC) • A1/O1 interface between RIC and NMS & Orchestration layer
  11. 11. British Telecommunications plc 2018 5G trial site with 64T64R M-MIMO AAU and 8T8R passive antenna with RU 11
  12. 12. British Telecommunications plc 2018 Base station architecture - 5G - EN-DC (Option 3x) 12 RU CU RU S1 interface DU RU DU D-RAN with AAU/RRU C-RAN with option 2 split C-RAN with option 7/8 split and further CU centralisation DU CPRI eCPRI CU S1 interface F1CPRI eCPRI CU S1 interface F1CPRI eCPRI Note: a site may support one or more base station architectures for different radio channels/bands Note: In full C-RAN configuration the DU and CU may be co-located or on separate sites
  13. 13. British Telecommunications plc 2018 RAN functional splits - protocol architecture (EN-DC) 13 RRC PDCP Data Low- RLC High- MAC High- PHY Low- MAC Low- PHY RF High- RLC RRC PDCP Data Low- RLC High- MAC High- PHY Low- MAC Low- PHY RF High- RLC Option 1 Option 2 Option 3 Option 4 Option 5 Option 6 Option 7 Option 8 Relaxed Very low End to end latency Traffic/capacity related Very high Capacity requirement Higher layer splits Lower layer splits S 1 CPRIeCPRIF1 Reference 3GPP TR 38.801
  14. 14. British Telecommunications plc 2018 Base station architecture - 5G - Next Generation Core (NGC) 14 RU CU RU N2/N3 interface DU RU DU D-RAN with AAU/RRU C-RAN with option 2 split C-RAN with option 7/8 split and further CU centralisation DU CPRI eCPRI CU N2/N3 interface F1CPRI eCPRI CU N2/N3 interface F1CPRI eCPRI Note: a site may support one or more base station architectures for different radio channels/bands Note: In full C-RAN configuration the DU and CU may be co-located or on separate sites (as illustrated)
  15. 15. British Telecommunications plc 2018 RAN functional splits - protocol architecture (NGC) 15 RRC SDAP/ PDCP Data Low- RLC High- MAC High- PHY Low- MAC Low- PHY RF High- RLC RRC SDAP/ PDCP Data Low- RLC High- MAC High- PHY Low- MAC Low- PHY RF High- RLC Option 1 Option 2 Option 3 Option 4 Option 5 Option 6 Option 7 Option 8 Relaxed Very low End to end latency Traffic/capacity related Very high Capacity requirement Higher layer splits Lower layer splits N 2 - N 3 CPRIeCPRIF1 Note: Service Data Adaptation Protocol (SDAP), has been introduced to the NR user plane to handle flow-based Quality of Service (QoS) framework in RAN, such as mapping between QoS flow and a data radio bearer, and QoS flow ID marking.
  16. 16. British Telecommunications plc 2018 RAN access network connectivity 16 RU DU CU S1 or N2/ N3 interface F1CPRI eCPRI Terms; Fronthaul, mid-haul and backhaul as defined by MEF (Metro Ethernet Forum) Fronthaul Mid-haul Backhaul Backhaul (in common use) CPRI, eCPRI or Non-ideal fronthaul
  17. 17. British Telecommunications plc 2018 5G within a multi-RAT network deployment - DRAN scenario 17 3G 4G1 5G CSG OSA -FC OSA -FC 21C MSE D W D M D W D M 21C MSE Mobile core networks2 21C IP/MPLS network (P routers not illustrated) Openreach Point to point DWDM solution Future-proofed for network sharing and RAN evolution n x λ (can bypass CSG) 1 - 2G is supported on the same base station as 4G (SRAN/Multi-RAT) 2 - Includes RNC for 3G and IP Sec GW for 4G and 5G PRTC sync source
  18. 18. British Telecommunications plc 2018 5G within a multi-RAT network deployment - DRAN scenario 18 3G 4G1 5G CSG OSA -FC OSA -FC 21C MSE D W D M D W D M 21C MSE Mobile core networks2 21C IP/MPLS network (P routers not illustrated) Openreach Point to point DWDM solution n x λ (can bypass CSG) 1 - 2G is supported on the same base station as 4G (SRAN/Multi-RAT) 2 - Includes BSC for 2G, RNC for 3G and IP Sec GW for 2G, 4G and 5G PRTC sync source E-Band
  19. 19. British Telecommunications plc 2018 5G within a multi-RAT network deployment - DRAN scenario 19 3G 4G1 5G CSG OSA -FC OSA -FC 21C MSE D W D M D W D M 21C MSE Mobile core networks2 21C IP/MPLS network (P routers not illustrated) Openreach Point to point DWDM solution n x λ (can bypass CSG) 1 - 2G is supported on the same base station as 4G (SRAN/Multi-RAT) 2 - Includes BSC for 2G, RNC for 3G and IP Sec GW for 2G, 4G and 5G PRTC sync source E-Band E-band link(s) could connect directly to a wavelength on OSA-FC product
  20. 20. British Telecommunications plc 2018 5G within a multi-RAT network deployment - Edge enabled 20 3G 4G1 5G CSG OSA -FC OSA -FC 21C MSE D W D M D W D M 21C MSE Mobile core networks2 21C IP/MPLS network (P routers not illustrated) Openreach Point to point DWDM solution n x λ (can bypass CSG) 1 - 2G is supported on the same base station as 4G (SRAN/Multi-RAT) 2 - Includes BSC for 2G, RNC for 3G and IP Sec GW for 2G, 4G and 5G 3 - Enables RAN functional decomposition, distributed UPF and service platforms PRTC sync source E-Band E-band link(s) could connect directly to a wavelength on OSA-FC product 5G Edge Cloud3
  21. 21. British Telecommunications plc 2018 5G demo at Canary Wharf 21 Highlights • 1.3Gbps to test equipment (30 MHz LTE + 40 MHz NR) • 600Mbps to Huawei 5G CPE (5 MHz LTE + 40 MHz NR) • 4T4R LTE (15 MHz 2100 + 15 MHz 2600) with 64T64R NR
  22. 22. British Telecommunications plc 2018 Summary • The functional decomposition of the RAN is at an advanced stage in standards, industry fora and implementation (XRAN/ORAN, 3GPP, ONAP) • Traditional 4G centric CRAN (CPRI based) is popular in Asia due to availability of dark fibre, this brings radio optimisation benefits through centralised scheduling etc. • CPRI doesn’t scale for 5G due to amount of spectrum and antennas therefore eCPRI was developed by the same industry partners who developed CPRI • Several industry groups are working towards a virtualised RAN to disaggregate the hardware from software for many functions, also enables innovative new entrants to market • Major RAN vendors offer a range of different RAN architectures to meet various deployment scenarios • BT is currently rolling out the radio, backhaul and core network infrastructure necessary to be a leader in 5G and converged networks 22 https://www.ngmn.org/fileadmin/ngmn/content/downloads/Technical/2018/180226_NGMN_RANFSX_D1_V20_Final.pdf
  23. 23. British Telecommunications plc 2018 Thank You Any questions? 23

×