It’s no secret that mobile operators are exploring virtualizing the radio access network (vRAN) to cut costs and make their networks more efficient. Dali Wireless believes it can take that a step further by streamlining the fronthaul network. Fronthaul is the connection from the base station baseband processing units (BBUs) to the remote radio heads on the tower.
Dali Wireless was founded in 2006 and originally intended to focus on the power amplifier market. But founders Albert Lee and Shawn Stapleton turned the company’s focus to the radio access network in 2009 when they suspected that the vRAN market would soon take off.
According to Lance Uyehara, director of telemanagement at Dali Wireless, the company has developed a patented virtual fronthaul interface that uses software-defined networking (SDN) to act as an intelligent aggregator-router. That interface sits between the virtualized BBUs and the radio heads on the tower, and makes it possible for multiple operators to connect to multiple BBUs, creating a multipoint-to-multipoint network.
In most network designs there is one operator connecting to one BBU from one vendor. For example, AT&T may have multiple vendors building its 4G network, but it will only have Ericsson equipment in a certain market and Nokia equipment in another market. What Dali’s technology can do is make it possible to aggregate signals from different vendor gear. “This is unique for Dali,” Uyehara said. “We can aggregate signals from different vendors to different operators. That routing function is unique.”
What This Means
This is important, according to Uyehara, because a more distributed network architecture means that operators could virtualize the RAN and the BBU but keep their existing radio heads, which will result in cost savings since radio heads are difficult to replace.
And it also makes new business models possible, which will be key as operators deploy 5G networks. For example, in campus environments where cellular coverage is necessary, it was often too costly for most companies to deploy a distributed antenna system (DAS). And if an operator did see value in deploying a DAS, it was only helpful for the customers of that particular operator.
However, using a vRAN with a virtual BBU and an virtual fronthaul connection, it is possible for an enterprise to have access to different operators. “It’s just an instantiation of a different operator,” Uyehara said. “You could have a Sprint or Verizon BBU on a virtual machine and have multiple operators running on the data center. But the operator controls things.”
Uyehara said that Dali Wireless is currently working with a number of companies on deploying its technology, and will have trials in 2018. The company is currently working on a “proof of concept” trial with a major North American operator that wants to get the technology in the field next year.