Optus, Ericsson test world-first 5G standalone aggregation

Optus and Ericsson have completed a 5G standalone carrier aggregation test across 180MHz of 2.3GHz and 3.5GHz spectrum on Optus's live network using commercial devices, describing it as a world first.

The test took place on Optus's commercial network at its Sydney campus using mainstream handsets, including Samsung's Galaxy S26 Ultra. The feature is already supported on devices on the network, including the Samsung Galaxy S24 and later series.

Spectrum setup

The work combined Optus's holdings in the 2.3GHz and 3.5GHz mid-band time division duplex spectrum bands to deliver what it said was a record 180MHz TDD spectrum aggregation. It formed part of a broader 5G standalone carrier aggregation setup that also used low-band and other spectrum bands.

Four-component carrier aggregation enabled 220MHz of downlink bandwidth across 900MHz, 2.1GHz, 2.3GHz and 3.5GHz. Two-component carrier uplink aggregation combined one frequency division duplex band from 900MHz and 2.1GHz with one TDD band from 2.3GHz and 3.5GHz.

At the live site, the setup reached peak downlink speeds of 3.4Gbps and uplink speeds of 200Mbps. Because the test used commercial devices rather than specialist laboratory equipment, the companies said it showed the approach was ready for operational network settings.

Network impact

For Optus, the announcement is the latest step in expanding standalone 5G features as operators look to improve network efficiency and support heavier data use. Carrier aggregation lets mobile providers combine multiple spectrum bands to increase available bandwidth and make better use of existing holdings.

The approach is intended to improve service quality for data-heavy uses such as high-resolution video streaming, augmented reality, virtual reality and large file downloads. The added capacity should also help maintain service quality in busy areas such as central business districts, transport hubs and large events when many users are connected at the same time.

Optus said the same 180MHz spectrum combination would also support 5G fixed wireless access services, where mobile operators use 5G networks as an alternative to fixed-line broadband for homes and businesses. More efficient use of mid-band spectrum is considered important for that market because it can support higher data demand while covering dense urban areas.

Rollout plan

The development builds on earlier work between the two companies. In 2020, Optus and Ericsson demonstrated a 2300MHz and 3500MHz 5G non-standalone carrier aggregation call. The new test marks a further move into standalone 5G architecture, which operators see as central to adding more advanced network features.

Optus plans to roll out the carrier aggregation feature progressively across metropolitan Sydney and Melbourne over the next 12 to 18 months, extending the technology beyond a single live test environment into wider use across parts of its urban mobile network.

No financial details for the rollout were disclosed. The feature will be available to customers with compatible devices and eligible 5G standalone plans on the network.

Sri Amirthalingam, Chief Technology Officer at Optus, said, "This achievement demonstrates how we are translating cutting-edge 5G technology into meaningful benefits for customers in real-world environments. Through our ongoing collaboration with Ericsson, we are unlocking greater capacity and performance across our 5G network, enabling faster speeds and more reliable connectivity. This milestone marks an important step in our network evolution towards 5G Advanced, reinforcing our commitment to remain at the forefront of innovation and to deliver tangible value for our customers."

Ericsson framed the result as a sign of how operators are combining more spectrum assets on live networks using standard devices.

"Optus continues to demonstrate strong leadership in adopting advanced 5G capabilities, and this milestone highlights the strength of our partnership. By expanding and combining multiple spectrum assets with Ericsson technology, we are helping Optus deliver meaningful performance improvements that translate directly into better everyday experiences for their customers," said Landgren.