AT&T picks Nokia to improve 5G uplink with DmMIMO

Nokia has announced Bell Labs is pioneering distributed massive MIMO (DmMIMO) with AT&T, an innovation that significantly increases uplink capacity and speeds in 5G networks without requiring an overly complex solution.

The enormous demand from new user experiences in the 5G-Advanced era will require greater uplink performance from networks. DmMIMO allows devices to leverage signal propagation to multiple cells or antenna panels in a network when establishing a link, thereby turning noise into a useful signal and increasing the uplink throughput.

The data transmission is pieced together from multiple antenna panels and cell sites through distributed baseband processing. The processing load between the cell site radio units and the central processing unit is split in a novel way, reducing the fronthaul capacity to cell sites and hence lowering the cost.

Nokia is collaborating with AT&T on the validation of DmMIMO and testing the proof-of-concept technology in the AT&T labs. Bell Labs’s DmMIMO simulations have demonstrated increases in 5G uplink capacity between 60% and 90% compared to similarly configured systems with a single panel. While other techniques come at the expense of downlink capacity, DmMIMO would produce sizable increases in uplink capacity without sacrificing performance.

AT&T Labs is providing expertise in validating new cutting-edge technologies in the lab and in the field. For example, AT&T Labs provided network deployment details for specific cities, which has been used for detailed ray-traced simulations to understand the benefits of DmMIMO in real-world scenarios.

Bell Labs is also benefiting from AT&T Labs’ 5G Testbed facilities with rooftops and poles connected by dedicated fiber networks to server racks in a lab environment. This capability enables experimentation to validate and improve the technology, leading to more effective deployment of the DmMIMO technology in the future.

Nishant Batra, Chief Strategy and Technology Officer, Nokia, said: “Addressing uplink speeds is becoming critical as consumers are increasingly becoming content creators as well as content consumers, video conferencing has become a cornerstone of the teleworking era, and many of the applications in the industrial internet of things require higher uplink speeds. When 5G-Advanced networks come online, we will see the network enhanced in multiple dimensions, expanding and extending its capabilities. Even today, with the focus on 5G mid-band spectrum rollouts in the U.S., there are opportunities for technologies like this that can maximize available resources. We feel distributed massive MIMO will be a critical element of networking in the 5G-Advanced era to help meet these demands with significant gains in uplink without a hit to downlink performance. Three decades ago, Bell Labs and AT&T invented MIMO, so it is only fitting that we continue this groundbreaking work together for the next generation of MIMO.”

Andre Fuetsch, Executive Vice President & CTO Network Services, AT&T, said: “AT&T and Nokia have a long history of working together on new network technologies, and I welcome this strategic collaboration for the development of distributed massive MIMO technology. Newer applications in the 5G-Advanced timeframe, such as eXtended Reality (XR), are expected to be more demanding on the uplink compared to regular broadband traffic. Technologies such as distributed massive MIMO show potential to improve uplink capacity in the right scenarios. DmMIMO is also a technology that shows potential for the next generation of wireless networks. Therefore, this strategic technology collaboration with Nokia may help provide learnings with long-term benefits to both companies.”

In addition to uplink improvements, the move to DmMIMO has the potential to alter the configuration of networks by facilitating deployments with smaller antenna arrays per site. This will lower weight, which in turn will result in smaller and lighter components as well as reduced power consumption. In alternate configurations, DmMIMO can also be used to boost downlink capacity, granting operators incredible flexibility in how they deploy the technology.