A trio of telecom juggernauts — Verizon, Ericsson, and Qualcomm — have successfully demonstrated the use of dynamic spectrum sharing (DSS) to allow 5G service to operate across different spectrum bands, including spectrum previously held exclusively for 4G LTE.

Verizon said it plans to commercially deploy DSS in the “near future” so the operator can make use of its full portfolio of spectrum for customers on 4G LTE and 5G. “As market demands for our services shift between 4G and 5G, we need to be able to shift our resources to efficiently meet those demands,” said Adam Koeppe, SVP of networking planning at Verizon, in a prepared statement.

Spectrum sharing isn’t entirely new, but the “dynamic” component is because it enables operators to deploy software that will automatically allocate spectrum from multiple spectrum bands on the same radio depending on real-time requirements within range of that equipment.

The technology is still, at least partially, theoretical because it remains under development and hasn’t been commercially deployed at large. Nonetheless, “DSS is a big deal and I think it’s underrated,” said Chris Antlitz, telecom principal analyst at Technology Business Research.

DSS is a software feature that can be baked into the radio access network (RAN) platform or added via remote provisioning, he explained. It’s a big deal for network operators because it’s going to save them a lot of money by removing previous requirements to completely refarm spectrum for new network technologies, Antlitz added.

“You can run out of the same spectrum band, out of the same radio, two technologies simultaneously and the traffic can be dynamically orchestrated depending on how much capacity is being asked from the system,” he said.

Verizon will continue to focus on providing 5G over millimeter-wave (mmWave) spectrum, especially in dense areas because high speeds and other forthcoming features are only possible through the amount of capacity available in high-band spectrum, according to Koeppe. “However, with dynamic spectrum sharing we will be able to supplement mmWave deployments and accelerate the deployment of 5G in low and mid-band spectrum for customers,” he said.

While mmWave “holds the vast majority of the potential of 5G and will be vital in dense areas … coverage is more important than capacity in the near term, and low-band and mid-band spectrum have the advantage there,” said Phil Solis, research director at IDC, in an email to SDxCentral.

“DSS will enable Verizon, who lacks low-band and mid-band spectrum for 5G, to roll out 5G with greater coverage,” he said. “Depending on how Verizon’s network is set up it may be able to push a software update across its network after further testing to enable it across the entire network sometime during the second half of 2020.”

The technology will also “make it easier for mobile operators to maximize spectrum for 5G without cutting off 4G devices, which will remain on networks for at least another 10 years, not counting cellular IoT endpoints, which will remain on mobile networks for much longer,” Solis explained.

The proof-of-concept demonstration, which occurred at Ericsson’s lab in Richardson, Texas, involved a DSS 5G data call running on Ericsson Spectrum Sharing, the vendor’s DSS offering, with Qualcomm’s Snapdragon 5G Modem-RF System and Verizon’s network.

Sprint is already using a variation of DSS on its massive multiple-input, multiple-output (MIMO) antenna systems that are being deployed for its slow-rolling 5G network to support 4G LTE and 5G New Radio (NR) concurrently. The operator has been taking down antennas that currently power 4G LTE in mid-band spectrum and replacing them with new units that feature 64 antennas and 64 radios in a single box.

DSS still requires more support from silicon vendors, network operators, and RAN vendors. “The network has to be provisioned for this, and devices have to support this. Only Qualcomm supports DSS at this time on its newest modem, the Snapdragon X55,” Solis said. “DSS can only be leveraged properly if a significant number of mobile devices have 5G and support DSS.”

Antlitz believes DSS will be commercially deployed with operators parsing workloads in a dynamic automated fashion from the same antenna unit within the next 12 months. “The telcos have a vested interest in widely deploying DSS as fast as possible to mitigate the burden of migrating people to 5G ultimately.”