Deploying massive MIMO for mid-band 5G presents the opportunity to massively reduce per site power consumption and system-level energy efficiency
While there isn’t anything magical that happens when a new year starts, it does represent the opportunity to renew focus, refresh ambition and revisit priorities. For mobile network operators (MNOs) that have invested several years and billions of dollars in building out 5G, the best is yet to come. Looking ahead at 2024, operators have the opportunity to continue the evolution of 5G, modernize legacy infrastructure, deliver impactful new services to customers, generate new revenue streams, and do those things while working towards achieving Net Zero targets and furthering collective work on climate action.
A key piece of linking up network and sustainability strategies is understanding that the two are not fundamentally at odds. With the right approach, operators can leverage modern infrastructure, software-based energy smart operations, and supply- and demand-side energy management tools, to reduce energy consumption without compromising network performance. With this knowledge, MNOs can now redefine the best 5G network using established KPIs like reliability, throughput and latency, by adding energy efficiency and sustainability.
In an interview with RCR Wireless News, Ericsson Head of Product Line 5G RAN Sibel Tombaz laid out a three-step approach in service of a larger transformation that she characterized as going from the “network machine” to the “network organism” The former is characterized as configuration-based, semi-static and algorithmic and the latter as intent-based, energy and user experience conscious, and a key enabler for societal digitalization.
The three-step strategy Tombaz detailed and Ericsson has successfully implemented with customers (more on that later), includes:
- Bringing sustainability to the center of network planning and adjusting KPIs
- Expanding and modernizing the existing network while scaling up 5G
- And using AI/ML and automation tooling for intelligent operations that boost energy savings
To the first step, network KPIs need to be redrawn to put sustainability at the fore throughout network planning, deployment and operations, Tombaz called out energy consumed by equipment measured in kWh, energy consumed per data volume measured in kWh/GB, and user experience metrics like uplink/downlink speeds. These measurements, taken as a whole, will inform “what is the best way to provide more with less,” she said. “We are really looking into providing the insights from multiple KPIs at the same time, so we are actually making the right input for our network design and optimization.”
Massive MIMO can be a massive benefit to operators’ sustainability roadmaps
Looking at the network as a whole, Ericsson Head of Radio Portfolio Management Tomas Sandin explained in a discussion that, “The RAN is taking the lion’s share of the energy consumption for our customers.” In fact, in a typical network configuration involving two multi-band radios for low-band and mid-band spectrum, and a massive MIMO radio, 80% of system power consumption comes from the radios. Onto step two—“The radio is the primary focus.”
While we’re five years into the 5G cycle, operators are still acquiring and deploying new spectrum, particularly in the mid-band which provides an advantageous balance of coverage and capacity when supported by massive MIMO antenna arrays. Because operators are rolling trucks and performing site work to deploy massive MIMO, there’s an opportunity to undertake a larger modernization effort that swaps out legacy infrastructure for more energy efficient, performant solutions. “The way we approach this,” Sandin said, “ is, of course,…radios that can do more capacity and performance, and at the same time less energy and embodied carbon. That’s really what we are all about.”
To support traffic growth in a way that doesn’t analogously drive up consumption, Sandin highlighted the importance of massive MIMO deployment as a key factor. “Bringing massive MIMO to the sites, because massive MIMO TDD is the most energy efficient technology there is when it comes to GBs/watt…[is] fundamental.” And if an operator is already touching a site, updating legacy RAN equipment can deliver more capacity, a lower tower load, “and on top of that we have energy saving features.”
What does that look like in the real world? Ericsson worked with Telstra to do precisely what Sandin described. At a set of sites in their home market, Telstra swapped out 12 legacy radios supporting low-band frequencies with three tri-sector radios for a 50% energy savings; six radios supporting mid-band FDD were replaced with three radios for a 27% energy savings; and legacy massive MIMO arrays were replaced with modern equipment for a 38% energy savings—so from 21 radios to nine radios per site. To Tombaz’s third step around leveraging AI/ML and automation, Telstra also is leveraging energy saving software, including Micro Sleep Tx for transmit and Cell Sleep Mode, and has future plans for MIMO sleep mode, AI MIMO sleep mode and baseband power saving. Network-wide, what Ericsson and Telstra put in place resulted in a 37MWh daily energy savings.
“We have a very large site reuse opportunity here,” Sandin said. “The massive MIMO of course provides lots of capacity, but also lots of efficiencies when it comes to GBs/watt. But I think it’s also worthwhile mentioning that our TDD bands have sort of great downlink capacity with massive MIMO but we are not viewing that as a singularity because we are capitalizing on the FDD bands we have on our site.” This combination, he said, allows for more capacity to be delivered more broadly without a massive densification push that brings more sites online–doing more with less. “And that’s really the fundamental baseline here, that we are not increasing the number of sites, but we are instead reusing the sites…So that jointly becomes a very strong proposition.”
In conclusion, Tombaz laid out the shared responsibility for climate action. “Our target as an industry, as a society, is very clear,” she said. “We need to leave a good future for our grandchildren.”
Use this content library to get more information on how 5G can be deployed and scaled more sustainably without compromising user experience:
- Report: Sustainable networks—the RAN modernization guide
- Article: Redefining the best network—energy efficient, high performing and sustainable
- Article: The climate science is clear—5G operators have a key role to play in meeting global sustainability goals
- Report: Ericsson Mobility Report, November 2022
- Report: On the road to breaking the energy curve–a key building block for a net-zero future
- Article: As operators scale 5G, sustainability is a business imperative
- Podcast: The Voice of 5G—network energy efficiency and new 5G statistics
- Article: For 5G and beyond, energy is as important as RAN, core and transport
- Podcast: Will 5G Change the World? featuring Ericsson North America Chief Technology Officer Mike Murphy
- Article: Ericsson and Vodafone halve network energy consumption in breakthrough 5G trial
- Article: IntraGrain makes agriculture smarter with with IoT
- Article: With the transition to 5G, operators can achieve societal, financial and environmental goals
- Report: Breaking the energy curve—An innovative approach to reducing mobile network energy use
