What is dynamic spectrum sharing and how is it progressing?
Dynamic spectrum sharing is increasingly being seen as a key feature in ramping up 5G New Radio roll-outs, by allowing LTE and 5G NR to co-exist in low-band spectrum currently being used for LTE — enabling carriers to establish a 5G coverage layer that does not require spectrum re-farming, and is more extensive than that provided by millimeter wave.
In September of this year, Ericsson and Qualcomm Technologies conducted the first 5G NR data call using DSS in FDD low-band spectrum. Both CEOs Hans Vestberg of Verizon and John Legere of T-Mobile US have made public remarks indicating interest in the technology, with roll-outs of DSS expected to come in the first half of 2020.
Andreas Roessler, technology manager for test equipment company Rohde & Schwarz, recently spoke about DSS at Mobile World Congress Los Angeles. In an interview with RCR Wireless News, Roessler discussed what DSS is and its progress toward development.
“The idea is, it gives a service provider that has no low-band spectrum available, the possibility to, step-by-step, roll out a coverage layer for 5G NR at low-band frequencies,” Roessler explained. Most operators, particularly those in the U.S., already have their low-band airwaves in use to support their extensive LTE networks — which are, and will continue to be, the workhorses which connect the vast majority of customers, most of the time. Mid-band spectrum for 5G is relatively scarce in the U.S. and other than the Citizens Broadband Radio Service auction next year of priority access licenses, there currently isn’t anything other than millimeter wave auctions on the horizon.
“DSS is actually the feature that’s being promoted by the industry to overcome that” lack of 5G-specific low- and mid-band spectrum, Roessler said. “We are working with the key players in the industry to verify and validate the feature. It’s coming in the second generation of devices and chipsets — they are to-be-launched, to-be-designed. But the feature is in test mode right now.”
Roessler discussed some of the features in 5G NR and LTE which come together and need to be aligned in order to allow the two technologies to operate in the same spectrum simultaneously. He also noted that in terms of what DSS enables, “there’s not really a boost in data rate to be expected. It’s really there to enable a coverage layer for 5G NR.”
He expects to see DSS begin to roll out in 2020, as part of the overall transition not just from 4G to 5G, but from Nonstandalone 5G — which depends on LTE to carry control-plane traffic — to Standalone 5G.
Watch the full video interview below:
See more of RCR Wireless News’ coverage from Mobile World Congress Los Angeles on our YouTube channel.
