AEWIN

5G基礎架構背後的技術介紹

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The Evolution of NFV

  • From closed, propriety, vertical to standard, commodity, horizontal hardware/software/platform.
  • Greatly reduce CAPEX and OPEX for telecom operators.
  • A new business model of virtualized, modularized, and customized micro-services (network slices).

Network Service Slice

  • Slice 1 – Enhanced Mobile Broadband network slice:
    CDN (Content Delivery Networking), ICN (Information Concentric Networking)
  • Slice 2 – Ultra Reliable Low Latency Communications network slice:
    IoV (Internet of Vehicles), V2V (Vehicle to Vehicle), V2I (Vehicle to infrastructure), V2X (Vehicle to anything)
  • Slice 3 – Massive Machine Type Communications network slice:
    IoT (Internet of Things)

The Evolution of Radio Access Network

1G/2G RAN: RRH/BBU collocated

Existing issues:

  • Base station must be located beside the antenna because of the rapid signal attenuation of coax cable.
  • Huge expense on air condition system for the base stations deployed outdoor.
  • Low utilization of base station resources.
  • Base stations are difficult to communicate with each other via X2 interface.

3G RAN: RRH/BBU function split

Solved issues:

  • Improve flexibility of deployment since theremote radio head function split from baseband unit.
  • Indoor BBU deployment can reduce air conditioning cost.

Existing issues:

  • Low utilization of base station resources.
  • Base stations are difficult to communicate with each other via X2 interface.

Additional issues:

  • Require low latency and accurate synchronization on Ir interface.

4G/B4G RAN: vBBU/RRH fixed function split

Solved issues:

  • Virtualized BBU pool deployed on a single hardware can reduce cost and increase resource utilization.
  • Save energy by reducing BBU hardware.
  • Centralized BBU pool makes base stations cooperate much easier.

Existing issues:

  • Require low latency and accurate synchronization on Ir interface.

Extra issues:

  • Require higher backhaul bandwidth on S1 interface.

The Next Generation RAN

Separate RAN into three units: CU, DU, and RU that make your deployment more flexible.

  • RU: The radio unit that handles RF and Low-PHY layer. The main considerations of RU design are size, weight and power consumption.
  • DU: The distributed unit handles High-PHY, MACand RLC layers. This node runs a part of gNB functions depending on the functional split option, and controlled by the CU.
  • CU: The centralized unit that handles PDCP and RRC layers.

The purposes of separating DU from RU:

  • Less intelligent RU costs less
  • The ability to control multiple RUs simultaneouslyto enable base station cooperation features like CoMP.
  • Sharing baseband resource

The Evolution of Core Network

4G Core Network: EPC (Evolved Packet Core)

  • Dedicated hardware and software for each network function.
  • Point-to-Point interfaces between network functions.
  • C/U plane are not completely separated.
  • High expense and difficult to maintain, upgrade, recover, or add new services for operators.

5G Core Network

  • Virtualized and modularized network functions on standard x86 servers.
  • Service-Based Interface instead of Point-to-Point.
  • Fully separated C/U plane.
  • Lower expense and easier to maintain, upgrade, recover, or add new services for customized network slicefor operators.

Multi-access Edge Computing

  • Highly reduce latency of RAN.
  • Highly save the bandwidth from core network to Internet.
  • Perform as a pivotal control/data/information node in between RANs and CNs or even the Internet clouds.

Performance Optimization

  • Specialized accelerators based on FPGA (or eASIC) and ASICs for offloading CPU on compute intensive FEC / LDPC tasks.
  • Lowering hardware requirement for DU allowing lower CAPEX and reducing energy requirement for lower OPEX

Summary

  • 5G is based on years of evolution in wireless technologies.
  • Introducing the possibility of using general purpose equipment as feasible alternative to expensive ASIC based proprietary solutions.
  • Lowering the hurdle for 5G deployment as well as making it possible for private entities to deploy their own private 5G networks.