Small Cells, DAS & Het-Nets

U.S. Front/Backhaul Market Forecast, 2017-2022: The Functional Split

5G looms over the network strategies of mobile operators, as does the ongoing move toward Cloud RAN (CRAN), software defined networking (SDN) and network function virtualization (NFV). All of this – along with many other factors – drives the need for reliable, scalable and cost effective fronthaul and backhaul.

Fiber is the primary physical medium for transporting control and user plane traffic among cell sites, the edge, the mobile core, data centers and the Internet. Wireless solutions have their place and scale reasonably well, but as traffic shifts from LTE to 5G and as mobile data demand grows, fiber is likely to remain the key medium for transporting user data (and control plane data) from cell sites to the core network. This is backhaul.

Remote radio heads (RRHs) are the mainstay of most RANs. Fiber links the RRHs to the baseband processing units (BBUs) at the bottom of the tower. This is fronthaul. Increasingly, those BBUs are being centralized at a place other than the bottom of each macrocell tower. The current technology of choice for linking BBUs and radios is CPRI. BBU centralization is the first step on the road toward Cloud RAN (C-RAN).

But, CPRI does not scale into tomorrow’s world of MIMO and Massive MIMO. The amount of bandwidth required to transport CPRI signals (digitized version of analog radio traffic) scales in relation to the number of radios, and on a cell site with dozens of antennas (and radios) the amount of throughput required would quickly scale into the terabytes per second. And while this might technically be possible with fiber and multiplexing (WDM), the cost would likely be prohibitive.

So, in the last few years, there has been a push to, essentially, rethink CPRI and create a new “functional split” between the radio and the baseband processing. There are multiple efforts underway to define a new standard (eCPRI, NGFI, Fronthaul Lite) and it appears likely that some version of the functional split will become part of the 3GPP standards releases. Essentially the goal of the functional split concept is to minimize the amount of traffic that has to pass over the fronthaul links. This market study provides an overview of the different efforts to that end.

This market study also provides a five-year forecast of the number of front/backhaul links to cell sites by type of medium (fiber, copper, or wireless) and by type of cell (macrocell or outdoor small cell). Finally, it forecasts the amount of mobile data demand that flows over those links by generation (5G and non-5G).


Key Questions Answered

  • What is the anticipated growth of front/backhaul in the U.S. through 2022?
  • How is traffic split between 4G LTE and 5G?
  • What is the difference between fronthaul and backhaul?
  • How is the type of front/backhaul split between fiber, wireless and copper?
  • What is the forecast for front/backhaul to support outdoor small cell deployments?
  • What are the major concerns of the mobile operators with regard to each type of backhaul and how can these concerns be addressed?
  • What is the role for wired and wireless front/backhaul in small cell architectures?
  • How is wired and wireless front/backhaul deployed?
  • How do PTP, PMP, NLOS, millimeter wave and traditional microwave solutions differ?
  • How do fiber (point to point and passive), VDSL2 and coaxial (hybrid fiber coax) differ?
  • How does wireless backhaul compare to fiber backhaul?
  • How does wireless fronthaul compare to fiber fronthaul?
  • What is CPRI and how may it change?

Who Should Read

  • Mobile operators, particularly those servicing the U.S. market
  • Mobile backhaul providers, including telcos and cable MSOs
  • Wired and wireless backhaul vendors and solution providers
  • Mobile OEMs, particularly those servicing the U.S. market
  • Wired and wireless infrastructure vendors, particularly those servicing the U.S. market
  • Financial analysts and investors.

Table of Contents

  • Abstract
  • Executive Summary
    • U.S. Front/Backhaul Forecast
  • Methodology
  • Basic Mobile Operator Network Architecture
    • Wireless Spectrum
    • Cell Sites
    • The Different Types of Haul
  • Basics of Front-/Backhaul
  • Wired and Wireless Backhaul Options
    • Copper
    • xDSL
    • G.fast
    • Coaxial cable / HFC
    • Fiber
    • Fiber Deployment Options
    • PON and PTP
    • Carrier Ethernet
  • Wireless Backhaul
    • Typical Mobile Backhaul Topologies
    • Point to Point (PTP)
    • Point to Multipoint (PtMP)
    • Non Line-of-Sight (NLOS) vs. Line-of-Sight (LOS)
    • Licensed vs. Unlicensed Wireless
    • Briefly: Millimeter Wave versus Microwave
  • The Case for and Against Wireless Front/Backhaul
    • Strengths
    • Weaknesses
    • Summary
  • Fronthaul Today: CPRI
    • What is CPRI?
    • Why Use CPRI / Fronthaul?
  • What is 5G?
  • Front-/Backhaul in the 5G World
    • The Functional Split
    • eCPRI
    • Fronthaul Lite
    • NGIF / Xhaul
    • 5G New Radio gNB and Functional Split Options
    • In-band front/backhaul
  • U.S. Backhaul Forecast
    • Major Assumptions
    • U.S. Cell Sites Deployed
    • Front/Backhaul by Type
    • Macrocell Front/Backhaul Forecast
    • Outdoor Small Cell Front/Backhaul Forecast
  • Mobile Data Demand by Network Generation and Backhaul Type
  • Mobile Front/Backhaul Vendor Profiles (Wireless and Wired)
    • Cisco
    • CommScope
    • Ericsson
    • Fujitsu
    • Huawei
    • NEC
    • Nokia Networks
    • ZTE Corporation
  • Wired Mobile Front/Backhaul Vendor Profiles
    • Accedian Networks
    • Actelis Networks
    • ADTRAN
    • ADVA Optical Networking
    • Calix
    • Canoga Perkins
    • Celtro Communication Ltd.
    • CenturyLink / Level 3 Communications
    • Charter Communications / Spectrum Business
    • Ciena
    • Coriant
    • Crown Castle
    • DASAN Zhone Solutions
    • ExteNet Systems
    • Fibrolan
    • Infinera
    • IPITEK
    • Juniper Networks
    • PalmettoNet, A Spirit Communications Company
    • Positron Access Solutions
    • RAD Data
    • SOLiD
    • TE Connectivity
    • Telco Systems
    • Windstream Communications
    • Zayo
  • Wireless Mobile Front/Backhaul Vendor Profiles
    • Airspan Networks
    • Aviat Networks
    • BridgeWave Communications
    • Cambium Networks
    • Cambridge Broadband Networks Limited (CBNL)
    • Communication Components, Inc. (CCI)
    • CCS
    • Ceragon Networks
    • DragonWave-X
    • E-Band Communications
    • EBlink
    • Exalt Wireless
    • Fastback Networks
    • Intracom Telecom
    • LightPointe Wireless
    • MAX4G
    • Proxim Wireless
    • RADWIN
    • Siklu
    • Tarana Wireless
    • Vubiq Networks
  • Definitions
  • About iGR
    • Disclaimer

List of Tables

  • Table 1: CPRI/ORI Interface Specifications and projected bit-rates for RRH Links
  • Table 2: Growth in Cell Sites, 2017-2022
  • Table 3: Front/Backhaul Links Deployed to U.S. Cell Sites by Type, 2017-2022
  • Table 4: Front/Backhaul Links Deployed to U.S. Macrocells, by Type 2017-2022
  • Table 5: Front/Backhaul Links Deployed to U.S. Small Cells, by Type, 2017-2022
  • Table 6: U.S. Bandwidth to be delivered per month (TB), 2017-2022
  • Table 7: Mobile Data Demand by Cellular Generation, 2017-2022
  • Table 8: Average Mobile Data Demand by Sector, 2017-2022
  • Definitions Table

List of Charts and Figures

  • Figure A: Front/Backhaul Links Deployed to U.S. Cell Sites by Type, 2017-2022
  • Figure 1: Basic Components of Cellular Voice/Data Network
  • Figure 2: Cell Site Backhaul Capabilities and Use Cases, Wired and Wireless
  • Figure 3: Simplified Example of an All Fiber PON
  • Figure 4: Simplified Example of a PTP Fiber Network
  • Figure 5: Wireless as a Mobile Backhaul Solution
  • Figure 6: Typical Mobile Backhaul Deployment Configurations
  • Figure 7: Possible Small Cell Backhaul Topology, Dense Urban
  • Figure 8: PTP Microwave Configuration
  • Figure 9: Typical PtMP Configuration
  • Figure 10: Millimeter Wave vs. Traditional Microwave
  • Figure 11: CPRI at the Macrocell and as Small Cell / CRAN
  • Figure 12: CPRI System & Interface Basics
  • Figure 13: Dimensioning CPRI 7.0 Links
  • Figure 14: Approximate Timeline of 5G Progress
  • Figure 15: eCPRI System and Interface Definition
  • Figure 16: eCPRI Functional Splits
  • Figure 17: NGIF Diagram
  • Figure 18: Splitting the Processing
  • Figure 19: Examples of CU-DU Functional Split Configurations
  • Figure 20: Growth in Cell Sites, 2017-2022
  • Figure 21: Front/Backhaul Links Deployed to U.S. Cell Sites by Type, 2017-2022
  • Figure 22: Front/Backhaul Links Deployed to U.S. Cell Sites by Type (Log), 2017-2022
  • Figure 23: Front/Backhaul Links Deployed to U.S. Macrocells, by Type 2017-2022
  • Figure 24: Front/Backhaul Links Deployed to U.S. Small Cells, by Type, 2017-2022
  • Figure 25: U.S. Bandwidth to be delivered per month (TB), 2017-2022
  • Figure 26: Mobile Data Demand by Cellular Generation, 2017-2022
  • Figure 27: Average Mobile Data Demand by Sector, 2017-2022

For additional information on the U.S. Front/Backhaul Forecast, 2017-2022: The Functional Split market study, please contact Iain Gillott, at (512) 263-5682 or by email.