What will the coexistence between 5G and 6G be like?

The Next G Alliance believes that 6G and 5G will coexist for a long period of time, as future 6G systems will be an evolution of 5G and not a replacement technology

It’s widely accepted by the industry that once 6G systems emerge near 2030, they will coexist for a long period of time with 5G and 5G Advanced technologies, as was the case with previous generations of wireless technologies.

According to Ian Wong, director of RF and wireless architecture at Viavi Solutions, the coexistence of 5G and 6G networks will be probably smoother compared to the coexistence of 4G and 5G networks, because 5G networks were designed with a more flexible framework than previous 4G networks. Wong believes that this flexibility in the architecture of 5G networks will pave the way for a smooth coexistence period between these technologies in the future.

“5G and 6G will need to coexist for an extended time. Deploying new network equipment is time consuming and expensive. Network operators who make the significant capital investment in deploying 5G infrastructure are not going to stop using it any sooner than they must, to extract the maximum profit from their investment,” said Sarah LaSelva, director of 6G marketing at Keysight Technologies.

“It’s easy to predict [that] 5G will remain active and in use for many years after 6G is available. Unlike previous generations, more functionality for 5G is being done in software and the RAN is becoming more disaggregated and cloud-based. This will allow for more upgrades between 5G and 6G without costly new deployments, but there will always be pieces of the network that will still require hardware upgrades or new installations,” LaSelva added.

Meanwhile, Patrik Persson, 6G program manager director at Ericsson, highlighted that 6G will operate in a wide range of frequencies, from below 1 GHz to 100+ GHz, where low and mid-band spectrum continue to be important, complemented by higher frequency bands in the mmWave and sub-THz range. “Hence, it is very important to coexist with 5G using a small number of well-defined alternatives for interworking. Dynamic spectrum sharing is a key technology and needs to be included in 6G from the very beginning to enable a fast and smooth migration to 6G as existing spectrum assets can be used,” Persson said.

According to Hiroaki Sato, of the 6G Infrastructure Group, Future Society and Technology Unit at Fujitsu, the coexistence of 5G and 6G is essential because most telecommunications carriers are expected to introduce 6G in stages, as was the case in previous generations. Another factor that would lead to the coexistence between the two technologies is that 6G alone may be available for local use or specific use in the case of the industrial sector centering on private communication networks, Sato said.

Mike Nawrocki, managing director of the Next G Alliance also believed that 6G and 5G will coexist for a long period of time, because future 6G systems will be an evolution of 5G and not a replacement technology. “6G will be built on top of 5G, and it will also extend many 5G applications, so like any previous generation technology, there is an overlap period. In the last couple of years, we’ve seen operators in the U.S., beginning to retire 3G technology. So there was a very long overlap period. We’d expect the same with 6G. So obviously, it will not be a kind of a replacement technology, it’s much more of an evolution, where 6G brings in new capabilities built upon where 5G was successful. But there is probably going to be a relatively long coexistence period between 6G and 5G technologies,” Nawrocki said.