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5G Backhaul Will Become the Next Growth Point in the Optical Communication Field

Number of visits: Date:2018-3-14 09:44

Abstract:

According to industry sources, 5G standard set by 2020, 5G mobile services will be officially opened. Previous generations of mobile communications first brought data and then transmitted the video to voice-only platforms. The 5G will increase support for traffic coming from the Internet of Things (IoT), dramatically increasing the number of network terminals. While 4G LTE can be considered as a replacement for cable broadband, the 5G's powerful performance will be enough for some users to use 5G services directly over Wi-Fi. Combined with the new mobile Internet of Things traffic, it can result in an unprecedented surge in mobile traffic.


With the introduction of 5G, this profound change in mobile services is expected to create new opportunities for optical networks. The latest analysis report published by the CIR shows that 5G deployments will mean more optical fibers in the backhaul, especially PONs.


All of this leads that optical fiber become the best solution to the data-rate and latency issues for 5G deployments, while also downplaying the fact that optical network is often the most expensive backhaul solution.

More Optical Fiber Inputs

The overall investment in mobile backhaul is unlikely to increase in the next decade. However, the CIR estimates that nearly 60% of mobile backhaul equipment investment worldwide will go toward optical links in 2022, down from less than 50% in 2017.


Given the uploading speed of the latest version of 4G LTE handsets is 300 Mbps, 5G terminals need to provide 10Gbps upload speeds. Similarly, 4G LTE can achieve a 45-millisecond delay and a 5-G delay a millisecond. Not all 5G applications require this level of performance, but those 5G-specific advanced services such as autonomous vehicles, augmented reality, and virtual reality require latency of 1 millisecond or less.


In view of this, 5G backhaul is bound to bring new benefits to the optical network business in the next decade. CIR analysis shows that by 2026, annual investment in 5G backhaul optical infrastructure will reach $1.5 billion. Millimeter wave (mmWave) will also play an important role in providing impressive delays and significant cost reductions. The 80GHz millimeter wave provides very low latency and 10Gbps data rates, but the transmission distance is only 3 kilometers.

5G Backhaul Becomes the New Development Direction of PONs

Even though there are technical advantages, expensive optical fibers are still an option, even though they can reduce their installation costs by making mini excavation tunneling. Passive optical networks (PONs) provide a more strategic solution to reduce costs and the costs associated with fiber. The use cases in the 5G backhaul are because PONs share fiber and use only passive components that meet the 5G latency, data rate, and distance requirements, with little difference to other non-fiber optic transport technologies.


Currently, the most suitable PON technology for 5G backhaul is NG-PON2. NG-PON2 can support four independent full-duplex 10-Gbps feeds. This is what the 5G backhaul needs, and every wavelength uses Ethernet to send 5G packets of information. Verizon has chosen the technology for its future 5G backhaul. Cisco, Nokia, Huawei, Calix, ADTRAN, Ericsson and Nokia are actively involved in developing this 5G backhaul technology.


The CIR predicts that in 2022 NG-PON2 and similar advanced PONs will have investment of $ 8.9 billion. Other investment channel sectors for fiber backhaul come from other PON technologies and other non-PON optical fibers.


PON will go far beyond FTTH in terms of data transmission rate and coverage, making PON a powerful and potential technology choice for local loops and metropolitan area networks.


While the major factors shaping the optical link market in the 5G backhaul are data rates, latency, and cost, we note that the 5G backhaul architecture and 4G LTE and earlier technologies will be different. In particular, the boundaries between fronthaul and backhaul will change, and this redesign of the mobile infrastructure will also affect the use of optical fibers in the backhaul.


Perhaps the most obvious way would be the CPRI (Common Public Radio Interface), which are the standard interface currently used for the connection between cellular tower radios (remote radio heads - RRHs) and the mobile network control backbone. CPRI, first defined in 2003, was intended to be used as a fiber optic interface to replace the copper cable that was then connected to the cell towers.


CPRI's data rate is from 614Mbps to 10Gbps, which seemed sufficient at the time, but in the 5G era it may not be enough. In particular, device suppliers have adopted MIMO technology for their 4G / 5G devices. MIMO uses multiple transmitters and receivers simultaneously, increasing data rate requirements. CPRI is not well adapted to the larger number of antennas in the 5G era, mainly because of MIMO.


However, CPRI does not fade quickly, but will continue to be embedded in most C-RAN architectures. However, there is increasing debate as to whether CPRI supports suitable 5G data rates. Some talk of reducing CPRI pressure through the use of existing packet networks is only a stopgap measure. In the long run, there must be a way to replace CPRI.


The IEEE is currently addressing this issue with its next generation interface group (NGFI 1914.1 Working Group). This working group was formed to define transport architecture for mobile outbound traffic. The NGFI will be rebuilt so that the outbound is supported as a bandwidth-adaptive multipoint-to-multipoint (mostly fiber) network in response to dynamic payload changes, supporting high-gain coordination algorithms and decoupling of numerous antenna interface traffic.

5G Backhaul Fiber: the Challenges and Opportunities Co-exist

In addition, other similar challenges will emerge. For example, CPRI data transmission is required over the short distance and including standard optical parameters such as time-base jitter error, power loss, and delay. However, as the emerging cloud RAN architecture is extended to 25 km, some of the optical performance parameters present some problems. This indicates that although the fiber is an important element that will dominate the 5G backhaul in the future, its deployment remains uncertain.

TypeInfo: Blog Articles

Keywords for the information:5G backhaul  fiber optic