How will microwave backhaul meet the 5G challenge?

Microwave backhaul was once considered a handicraft oddity but today it is omnipresent in virtual fiber networks. This wireless transport media has been innovated and re-invented to meet the backhaul needs for every new mobile system generation – from 2G to today – with each providing new services and supporting much higher data rates.

Still, you could (almost) be forgiven for asking if microwave backhaul will be up to the challenge of supporting 5G networks, with their massive and highly variable needs.

And an honest answer to that question is: “Yes, beyond any doubt.”

Insights into mobile backhaul, spectrum use and more

The 2017 edition of the Ericsson Microwave Outlook was released on December 14 featuring statistics and forecasts on mobile backhaul, insights on future spectrum use, as well as highlights of emerging microwave backhaul innovations.

The major network and technology driver in this area continues to be evolving capacity needs. With the buildout of LTE, the appetite for mobile broadband backhaul capacity has increased as expected, a trend that will continue with the arrival of 5G. It is forecast that, by 2022, the typical backhaul capacity for a high-capacity radio site will be in the 1Gbps range, rising to 3–5Gbps by 2025. We also predict that 80 percent of sites in an advanced mobile broadband network will still be operating under 350Mbps in 2022, though by 2025 this will have increased to 600Mbps.

Initial 5G network deployments are already on the horizon along with the rising traffic density and new high-capacity radio interfaces that will come with them. Microwave backhaul deployments of up to 10Gbps have become a reality with the growing focus on 5G readiness. The industry is also working on solutions for the next decade supporting towards 100Gbps using new frequency bands and innovative technologies.

Microwave backhaul is dead – long live microwave backhaul

I have worked with microwave backhaul since the mid-1990s, and it has been a privilege and an amazing journey. And it will continue to be so. As discussed in the report, many new innovations are now emerging for the next decade, including the multi-band booster and dual band antennas. These deliver a massive improvement in the performance levels of microwave backhaul, while at the same time accelerating the important shift toward the use of higher frequency bands.

There are also tireless research efforts into going beyond 100GHz frequency bands and MIMO technologies to breach the 100Gbps dream limit and ultimately make this a commercial reality.

Overall, mobile network backhaul will continue to evolve globally with a mix of fiber and microwave, driven by two major trends: the introduction of 5G by advanced mobile broadband operators and the expansion of LTE networks by most other operators. According to the Ericsson Mobility Report Q4 2017, 3.3 billion mobile broadband subscribers will be added in the next five years, and a clear majority of these will come from LTE and 3G/HSPA in microwave-centric markets, particularly due to the increasing number and size of LTE deployments in India.

Looking at the full picture, the share of radio sites connected by microwave will continue to be high and exceed 65 percent in 2022, excluding China, Korea, Japan and Taiwan. Governmental initiatives are driving a very fiber-centric approach in these countries, which is not reflected in how other markets are evolving.

The large-scale 5G volume deployments are initially expected in areas with high fiber penetration, such as China, Korea, Japan and US. However, operators that have a combination of microwave and fiber are also looking at introducing 5G, specifically in Western Europe where operators have as high as 80 percent microwave-based backhaul.

Spectrum – the dust is settling

Evolution is all about change, but uncertainties can cause some worries. As discussed in the report, the 5G spectrum situation is now becoming much clearer, driven by the intense efforts on pioneering deployments in leading countries and regions by 2020. 5G will eventually be introduced in some bands that today are used for microwave backhaul. E-band will therefore grow in use and importance for backhaul, and we will also see an introduction of new backhaul bands around and beyond 100GHz.

For a deeper dive, please visit our page featuring the Ericsson Microwave Industry Outlook report for 2017.