Examining the Fronthaul Network Segment on the 5G Road Why Hybrid Optical WDM Access and Wireless Technologies are required?

Transcription

1 Examining the Fronthaul Network Segment on the 5G Road Why Hybrid Optical WDM Access and Wireless Technologies are required? Philippe Chanclou, Sebastien Randazzo, 18th Annual Next Generation Optical Networking Congress 29th June 1st July 2016 Day Three, Friday 1st July Nice Acropolis France

2 Co-Ax The Radio Access Network architecture : state of art The current mobile architecture with distributed RAN equipment. Standard BS Traditional Site Site BS Radio BBU Backhaul Copper M-Wave Fibre Backhaul aggregation Central office Backhaul access Base band units Backhaul cell site Ethernet / Fiber Antenna Radio unit CPRI

3 Optical Ethernet backhaul The backhaul cell site is an aggregator of BBUs for data traffic based on 1Gbit/s Ethernet interface with synchronization (SyncE, IEEE 1588). European benchmark of Ethernet leased line: Considering the market for the provision of high quality services for business use (Mobile), this benchmark analysis describes the availability, standard prices for Ethernet leased lines supplied by former incumbent operators in the EU. Incumbent reference Offer Ethernet leased line charges for a local access 5km 24 months A wide variation in charges can be seen especially at speeds of 100M and above, which are typically provided via a fibre connection. source: November 2014, Wik-consult repport

4 Fibre Fibre Fibre The Radio Access Network architecture : state of art «Cloud RAN» The current mobile architecture with centralized RAN equipment: Phase1 : BBU centralisation (BBU-RU link based on CPRI/OBSAI) Phase 2 : BBU pooling Optimal architecture for CoMP RAN features (intra and inter-cell sites). Down sizing the form factor of equipement at the cell site Backhaul aggregation Antenna BBU Remoted Remote Head Site (RRU) Site BBU Centralised Phase 1 CRAN 3 cells (1 3 cells (1 site) per site) per BBU BBU Site 1 Site 2 Base band units Radio unit BS Radio BS Radio Central Office BS Radio CPRI/OBSAI over Fiber BBU BBU1 X2 BBU2 Backhaul Copper M-Wave Fibre Backhaul Copper M-Wave Fibre Backhaul Copper M-Wave Fibre Central office Fronthaul access

5 Hits The Radio Access Network architecture : state of art «Cloud RAN» Reach between cell sites and Central office: For urban area (high &middle density) : 75% links have length < 4km 95% links have length < 8km 99% links have length < 20km The existing network infrastructure is compatible with the fronthaul timing limitation (RTT < 150µs) Backhaul aggregation Central office Cell site to Central office reach Fronthaul access km

6 Optical fronthaul (CPRI, OBSAI, ORI) Passive Active & Semi Active Fiber-rich network to shared fiber

7 Wireless fronthaul (CPRI, OBSAI, ORI) From Small cell or 4 th sector Native wireless with spectral efficiency to Macro cell With wireless fronthaul, turn existing macro site into local C-RAN Easier and faster deployment, same network architecture than short reach fiber network

8 Expected peak cell site throughput Radio evolutions from 4G Adv to 5G+ 100Gbps 25Gbps The ultimate 5G Mm Waves High bandwidth Full Massive MIMO 2Gbps 1Gbps 300Mbps 5G+ First 5G 4G Adv More Carrier Aggregation 256 QAM MIMO 4*4 700MHz (wide range of coverage) 3.5GHz with Massive MIMO Ultra Low latency Time

9 The Radio Access Network architecture : the coming «5G» The target step of RAN architecture is the virtual RAN where a reconfigurable hardware is used. This architecture facilitates the dynamic adaptation of processing resources to the traffic request of available Radio Access Technology. Open functional splits with L2 or L1interfaces BBU & RRH partitioning BBU L3 & L2 L2 & L1 RRH vbbu CPU & real time constants O A M X 2 L3 S 1 R R C P D C P R L C L2 M A C F Q E A C M L1 ressource mapping F F T CPRI OBSAI R F Fronthaul bandwidth Low High Service PDCP RLC RLC MAC MAC MAC PHY Split PHY CPRI OBSAI CoMP capability DPS, CS, CB, CoMP: Coordinated Multi-Point DPS: Dynamic Point Selection CS: Coordinated Scheduling CB: Coordinated Beamforming JT/JR JT: Joint Transmission JR: Joint Reception

10 The Radio Access Network architecture : the coming «5G» The low part of the BBU (L1 and potentially a part of L2) cannot be virtualized due to CPU and real time constraints The high part can be virtualized (L3 and a part of L2) The virtualization is explicitly assumed to be part of the 5G architecture and design principles vran is a prerequisite of the network slicing vbbu L3&L2 Master central office (Data center) Load balancer & switch Ring Aggregation Network Cell site aggregator L1&L2 Ethernet / Fiber Antenna Radio unit Access Network

11 The Radio Access Network architecture : the coming «5G» L2 & L3 virtualisation The optimal architecture for CoMP inter cell sites should request: L1 & L2 Centralisation Pool of cell site aggregators : still CPRI/OBSAI network segments vbbu L3&L2 Antenna Master central office (Data center) Ethernet / Fiber Ring Aggregation Network Pool of cell site aggregators L1&L2 CPRIs over Fiber Radio unit Access Network

12 The Radio Access Network architecture : the coming «5G» Backhaul & Fronthaul architecture evolution: Aggregation Network Access Network Cell site 3 sectors 20 MHz MIMO4x4 Additional data rate: - minimum +20% of backhaul - maximum x3 of backhaul Ethernet Backhaul 300 Mbit/s (1GEth) BBU BBU pool CPRI : 3 x 5Gbit/s (3 ) 100µs / 20 km vbbu Ethernet New Functional Split 360 Mbit/s <? < 900 Mbit/s 2ms / 400 km Cell site gateway

13 Transmission line rate Mobile Backhaul and Fronthaul line rate Gbit/s 100 CPRI/OBSAI rate per RRH Compressed CPRI rate per RRH Eth. cell site gateway (new functional split) Eth. Backhaul per BBU pool Eth. Backhaul per cell site 2G 3G Radio Access Technologies 4G to 4G++ 5G to 5G+

14 Mobile backhaul and fronthaul optical technologies for last miles Aggregation Network Access Network (last mile network segment) Cell site

15 Mobile backhaul and fronthaul optical technologies for last miles Aggregation Network Access Network (last mile network segment) Ethernet backhaul Cell site 3 sectors 20 MHz MIMO4x4 PtP switch (1G 10G Ethernet Backhaul 40G 100G) PtP router 300 Mbit/s (1GEth) Switch BBU FTTH ONT G/XGS-PON (synergy with FTTH roll out)

16 Mobile backhaul and fronthaul optical technologies for last miles Aggregation Network Access Network (last mile network segment) Cell site 3 sectors 20 MHz MIMO4x4 BBU BBU pool CPRI/OBSAI/ORI fronthaul Mux/DeMUX Transceivers WDM technology : CWDM, DWDM, PtP WDM CPRI : 3 x 5Gbit/s (3 ) Potential synergy with FTTH roll out (supernumenary fiber, sharing 100µs / 20 km infrastructure with wavelength overlay)

17 Mobile backhaul and fronthaul optical technologies for last miles Aggregation Network Access Network (last mile network segment) Cell site 3 sectors 20 MHz MIMO4x4 BBU BBU pool Transceivers vbbu New backhaul for new functional split PtP router (1G 40G 100G) Switch Ethernet New Functional Split FTTH ONT 360 Mbit/s <? < 900 Mbit/s XGS-PON, NG-PON2 TWDM or PtP WDM (synergy 2ms with / 400 FTTH km roll out) Cell site gateway

18 Optical access trends for Mobile application Last-mile mobile backhaul context-synthesis: Mobile backhaul is done by DSL or fiber PtP with Switch/Router. Fiber will the enabler medium of backhauling Mobile backhaul is already supported by G-PON (with synchronisation feature) Tomorrow, more antenna sites & more data rate (5G) require: synergy with FTTx roll out new PON generation : XGS-PON, NG-PON2 (TWDM & WDM-PON) FTTH context-synthesis: What G-PON offers in term of bit rate, is enough for the backhaul 2G/3G/4G. XGS-PON will be soon available to support 5G WDM in access is in progress by NG-PON2 to support PtP WDM or TWDM (100G) Data rate capacity of FTTx - PON system (Down-/Up-stream) 100 Gbit/s 80/80 Gbit/s 40/10 Gbit/s 25/25 Gbit/s 25/10 Gbit/s TWDM-PON & PtP WDM PON ITU-T G.989 the potential 100G-PON the potential 25G-PON 10/10 Gbit/s XGS-PON 10/2,5 Gbit/s 2,5/1,25 Gbit/s G-PON ITU-T G.984 XG-PON 1 ITU-T G.987 ITU-T G ? grey optics WDM optics Timeline

19 Optical access trends for Mobile application

20 Conclusion 4 keys points 1 CPRI fronthaul 2 experimentations in France in opportunist mode 3 New functional split based 4 Heterogeneous on Ethernet is coming for 5G Fibber has the preferred medium of X -hauling last-mile: -PtP Ethernet (switch/router), -PON for FTTx synergy, -WDM for efficient sharing

21 Thank You. Acknowledgment: