Spectrum sharing with 4G is key to getting 5G off the ground

• Ericsson highlights its 4G/5G spectrum sharing approach
• Will enable CSPs to offer, at low incremental cost, broad 5G coverage
• A useful bait to win those key early 5G adopters

Interesting changes are noticeable in the way 5G technology is being marketed to telcos by the equipment vendors. The big vision of a vigorous roll-out of full blooded NR utilising new spectrum is probably still there (in the background now that the race to 5G is over), but now key messages are more likely to be about how CSPs can deploy 5G cost-effectively.

The subtext here is that as there may not now be a huge push for 5G by users for a few years (and therefore no commensurate immediate rise in real data demand) so CSPs can safely glide 5G spectrum support into their operations without going overboard on spending.

Which is borne out by Ericsson’s most recent marketing communication, where it’s having another go at highlighting its ‘pioneering’ spectrum sharing approach to 4G-to-5G generational change. We’ve heard about this before, of course, but now the drumbeat is going up a notch with the news peg that, with Qualcomm, Ericsson has pulled together the world’s first 5G data call via (deep breath) “spectrum sharing on a  3GPP Frequency Division Duplex (FDD) low band using commercial hardware and software based on Ericsson Radio System, and a mobile test device powered by Qualcomm's Snapdragon X55 5G Modem-RF System.”

As 5G commercial rollouts move ahead, claims Ericsson, spectrum sharing represents an attractive option for service providers looking to rapidly roll out 5G on FDD bands without the need to re-farm spectrum. 

This is a big deal, claims Ericsson, because frequency sharing had never been done between any cellular generation since 2G. Now, however, the “ technology is poised to change how new generation radio access technologies are introduced in operator networks using one of the most limited resources in mobile, which is spectrum.”

Ericsson says that “traditionally, new generation radio access technologies are deployed on separate spectrum blocks – as was the case with 2G, 3G and 4G. This would require operators to buy new spectrum or re-farm the existing spectrum to allocate the new generation. This is a very slow and costly process. Spectrum re-farming could take a decade but with spectrum sharing, this can be done overnight. Dynamic spectrum sharing revolutionizes the introduction of new technologies with a breakthrough innovation that allows the deployment of both 4G and 5G in the same band and dynamically allocates spectrum resources between 4G and 5G based on user demand.”

Indeed, it claims Dynamic Spectrum Sharing (DSS) is now emerging as a key part of mobile service providers’ 5G strategy and claims its spectrum sharing tech has the lowest total cost of ownership (TCO) for CSPs wanting to launch 5G in bands currently used for 4G. That means that operators wanting to shift users onto plans based on new 5G capable smartphones can do so a short time after launch with a simple software change (if they have the appropriate Ericsson kit, of course). Ericsson says it’s based its solution on intelligent scheduler algorithms that enable optimal use of both LTE and 5G on a single block of spectrum.

Ericsson also provides an opportunity for service providers to extend the coverage of new 5G NR mid and high bands by applying ‘Inter-band NR Carrier Aggregation’ between low-mid and low-high frequency bands. Again, spectrum sharing is key as it allows an easy introduction of NR on low bands and, in combination with NR Carrier Aggregation, spectrum sharing can double the coverage area of new 5G mid and high band cells, delivering hundreds of megabits per second indoors and at the cell edge.