A key theme at MWC 2024 was sustainability, and reducing energy costs is now a key concern and priority for all mobile operators. Although the discussion nowadays focuses mostly on active antennas and how network operators can deploy 5G, most global networks are still powered by passive antennas, which are also following sustainability enhancements. These are now referred to as “high-efficiency” antennas, highlighting that their design, manufacturing, operation, and technology are taking sustainability into account. These antennas have recently taken a significant step toward being adopted in the mainstream, from previously being discussed as a theoretical concept. These traditional passive antennas have inherent energy losses, achieved through both their design and the manufacturing process, which all add to increased energy output, and thus more Carbon Dioxide (CO2) emissions. With base stations and their attached antenna units totaling 57% of all electrical power consumption in the passive antenna network, this is a key area for vendors to target in reducing their energy output while increasing their Radio Frequency (RF) efficiency.
Currently, multiple vendors are working on high-efficiency antennas, but only a few of them are already shipping these innovative platforms to the market. For example, PROSE Technologies released its high-efficiency antenna system (branded the Xtrem Platform) that integrate air stripline structures, architecture that reduces significant soldering joints, and the use of eco-friendly designs resulting in improved energy savings of 15% over legacy platforms with low inter-modulation. Other vendors, including Huawei, released their “green antennas,” Comba is working on its Helifeed platform, and CommScope on its Seed platform. These alternative design approaches underscore the importance of new platforms for the industry. While other suppliers are working on high-efficiency antennas, the European, Chinese, and American vendors, respectively, are among the technology leaders in this field.
How Will Green Antennas Make the Cellular Network More Sustainable?
New antenna designs prioritizing environmental sustainability are demonstrating significant potential for operators. Industry-leading vendors are reporting energy savings of a 25% reduction in base station energy consumption during peak hours through innovations like optimized antenna structures, green materials, and sustainable manufacturing. These advancements offer a convincing value proposition for wider adoption, as green antennas can reduce the network footprint while maintaining performance and coverage, a challenge that traditional passive antennas have not effectively tackled.
Vendors have optimized increasing sustainability throughout the lifecycle of the antenna through a variety of methods:
- Highly Integrated Architecture: These technologies utilize air-type striplines instead of feeder cables to integrate the dipole array and feeding network. This results in a reduced length of internal cables and requires fewer solder joints and screws. This can benefit the cellular network in two ways: by reducing the insertion energy lost through the cables and during the manufacturing process by reducing CO2 from soldering points and non-recyclable plastic used in cables (60% of the total used inside an antenna).
- Recycled Materials: As highlighted by PROSE’s green initiatives, using recycled materials will enable old antennas to be refurbished and reused in the antenna ecosystem, saving on new manufacturing costs to produce new antenna components from scratch.
- Improved Network Efficiency and Spectrum Utilization: Green antennas enhance signal directionality where the signal is focused more precisely in the desired direction, with this approach reducing the power needed to achieve the same coverage area compared to traditional antennas that might wastefully scatter signals. This also translates into improved network efficiency and potentially frees up valuable spectrum resources that could be used for increased capacity elsewhere, also reducing the number of base stations required to lower the network’s overall energy output.
Green Antennas: Recommendations for Sustainable Network Evolution
Green antennas hold immense promise for cellular networks, offering compelling benefits, including improved network efficiency, cost savings for operators, and a significant boost to sustainability efforts. Their widespread deployment requires addressing several technological and ecosystem challenges that can be addressed with several industry initiatives, starting with an industry-wide acceptance and drive that green antennas should be the industry norm, and perhaps parts of their technology could even be standardized. Vendors should follow these efforts by improving the durability and sustainability of their materials, optimizing antenna designs for various frequencies (such as 5G), and integrating with technologies like air stripline architecture for increased efficiency. Vendors should consider the entire lifecycle of the antenna, rather than just its operation, including manufacturing and even decommissioning. Furthermore, creating specific green antenna alliances could support and accelerate Research and Development (R&D) and provide a healthy competitive environment.
Operators should also start embracing green passive antennas and even upgrade their existing antennas to take advantage of the newer, more energy-efficient designs. In any case, newer passive antennas can consolidate multiple frequencies into a single unit, making them both cost- and energy-efficient in the long term. Operators could pursue case studies of small-scale deployments with vendors to demonstrate antenna efficiency, energy savings, and the Return on Investment (ROI) to incentivize wide-scale adoption of this sustainable antenna practice. Even in the case where "off-the-shelf" green antennas are not optimized for energy savings or cannot seamlessly integrate into the existing infrastructure, operators can partner with vendors to share their specific needs and deployment challenges, allowing vendors to tailor green antenna solutions for maximum efficiency and compatibility. Green antennas now sit at the crossroads of technical innovation and environmental sustainability. These antennas transmit Radio Frequency (RF) signals in a much more efficient manner and are a critical step forward.