Dynamic spectrum sharing lets operators side-step the spectrum re-farming process
Right now in the U.S., 5G availability is relatively limited. AT&T, T-Mobile US and Verizon are all currently using millimeter wave frequencies so only parts of some markets have coverage. Sprint is using its 2.5 GHz to provide wider area coverage than what’s possible with millimeter wave. All four, three if you project a finalized merger between Sprint and T-Mo, have discussed plans for nationwide 5G coverage at some point in 2020. So how do we can from limited coverage today to pervasive coverage next year? A number of ecosystem players see dynamic spectrum sharing as a way to quickly scale 5G.
Dynamic spectrum sharing essentially lets an operator use the same spectrum at the same time for LTE and 5G. That means rather than re-farm spectrum in support of 5G, LTE bands can also carry 5G traffic via a software upgrade. So, spectrum re-farming–slow and expensive; software update–fast and more cost effective.
With operators like Verizon planning to introduce dynamic spectrum sharing in 2020, Ericsson this week announced it used dynamic spectrum sharing–under the product name Ericsson Spectrum Sharing, to complete a 5G data call over low-band FDD spectrum. Conducted at an Ericsson lab in Canada, the call connected an LTE/5G macro radio to a Qualcomm mobile test device equipped with the Snapdragon X55 multi-mode 5G modem, RF front end and other components.
All of the Ericsson Radio System gear sold since 2015 can support the software upgrade needed for DSS. To extend 5G coverage in millimeter wave bands, as well as low- and mid-band frequencies, “Classically I’d need to re-farm,” Ericsson’s Paul Challoner, head of network product solutions in North America, told RCR Wireless News in an interview. “What DSS does is allows me to use an existing LTE band to share that band dynamically…to support them both on that same band.”
He also pointed out that even if an operator had an empty band, they’d still have to add another radio or add an additional channel on an existing radio. DSS lets operators avoid those truck rolls and capex with its software-based functionality. Challoner said there would be “full software capability” for DSS by the end of the year. “We’re very excited about DSS and the capabilities that it brings.”
In addition to the coverage angle, Qualcomm’s Dean Brenner, vice president of spectrum strategy and technology policy, said DSS will also serve as “a very important bridge” from non-standalone 5G to standalone 5G. “DSS is pushing 5G coverage out as expansively as possible. So that means when the 5G core is launched, you’re already going to have this very, very broad 5G coverage. If you didn’t have DSS, you have kind of two problems–you have to get to the 5G standalone core but you also have to get 5G built out.”
