Mobile telecommunications carriers Telstra and Vodafone Australia have found themselves at odds with wireless ISPs and satellite operators over the use of the 3.6GHz spectrum band, which is being promoted by the regulator for 5G.
Speaking during the Australian Communications and Media Authority's (ACMA) Spectrum tune-up: Future use of the 3.6GHz band event on Wednesday, Telstra GM of Network and Technology Regulation Brian Miller pointed out that the international mobile industry is focused on two bands for 5G: The 3.4-3.8GHz band and the 24-30GHz band.
In order to fall in line with international harmonisation of 5G standards and devices, the ACMA must therefore make the 3.6GHz band available to telcos, Miller said, telling ZDNet that Telstra could make use of the band for its 5G trial network next year.
"We are looking at doing some trials ... about the time of the Commonwealth Games and on the Gold Coast -- not as part of the Commonwealth Games, I might add -- and we are looking at both the 3.6 and the 26GHz bands as being potential bands for those trials," he said.
In what Vodafone chief strategy officer Dan Lloyd called a "rare opportunity to agree with Telstra", he said multiple standards bodies from the operator and vendor communities worldwide are confirming that the 3.6GHz band will be used for 5G.
"3.6[GHz] is really what we call the sweet spot, where the coverage is good enough, it's a low enough band, where there's potentially enough spectrum available for these exponentially larger needs, and where the vendors are already driving for the deployment of the key technologies beamforming and MIMO," Lloyd said.
"For us to realise all of the potential of 5G technology, we think we're going to need the 3.6GHz band, we're going to need it configured as TDD, and we're going to need much larger quantities of spectrum than we've traditionally operated on."
Vodafone thinks operators will need up to 100MHz of such spectrum, with Lloyd pointing out the concern that presently, there is only 125MHz of the 3.6GHz band available -- meaning it will have to be reallocated from its current uses.
According to Miller, Telstra needs access to the spectrum by next year, with early access being "absolutely critical" for Australia to remain a mobile network leader as it has been for 3G and 4G.
While Vodafone sees certainty on access to spectrum as being important, Lloyd said the telco is less stringent about the timeline of actual access to the band.
"We have a slightly more nuanced view than Telstra; we do need certainty on access to the spectrum as soon as possible -- if that could happen in 2018, that, we think, is ideal," he said.
"We don't need to actually deploy in 2018. The standards are moving very fast now, but they're still in a relatively early phase, and if we're really going to reap the benefits of the international harmonisation and alignment, and we're going to substantially change the network architecture of our entire network and deploy new radio equipment, that is going to take some time."
Lloyd told ZDNet that Vodafone's likelihood of launching a commercial 5G network in 2020 is therefore reliant on both spectrum availability and whether the standards will be finalised over the next year.
"It remains to be seen, because the critical element spectrum availability is still highly uncertain," he explained to ZDNet.
"We have said very publicly that our aspiration is to deploy in 2020; if we can get certainty on access to the spectrum in 2018, then we can certainly start to deploy. It will be as quick as possible, but a relatively modest deployment to soak up the capacity in those areas that most need it.
"It's driven partly by the spectrum availability, but also the development of the standard, and we think if we started to deploy next year, we're at risk of having to deploy modified bespoke versions of the standard that we might quickly discover that we regret that we didn't wait six months or 12 months longer to deploy. But if all of that lines up, and that's clearly quite a balancing act to get all those elements together, then certainly we can see some significant deployments in 2020."
Incumbent users of the 3.6GHz band, meanwhile, argued that the spectrum should not be taken away from them and given to mobile telcos.
Bob Horton of the Communications Alliance Satellite Services Working Group accused the ACMA of being "currently mesmerised by a mobile broadband strategy" and being on an "unexpected, high-risk path".
According to Horton, the ACMA is proposing to create a "super primary" status for mobile broadband providers.
Instead, he promoted an option that involves proceeding to spectrum licensing immediately in areas most suitable for 5G according to MBB providers; existing and future primary service providers continuing business as usual; no super primary status to be awarded to telcos; licences to be given a 15-year lifetime; and "auction windfalls to government" to be prevented.
Wireless ISPs are also current 3.6GHZ users, with Lynda Summers of the Wireless Internet Service Provider Association of Australia (WISPAU) pushing a program of spectrum sharing instead of taking spectrum away from incumbents to give to telcos.
"Is this the tipping point for us to have a serious look as a nation at some very structured approach to spectrum sharing?" she said, pointing out that fixed-wireless services could even provide their own 5G networks.
"Our preference is for just allowing the 5G at the present time into the metropolitan areas and leaving the regional ISPs alone, because we think we have prospects as well in the 5G space if all the promise that's out there about what it can do is true," she said.
In response to Summers, Lloyd said that as a proponent of infrastructure sharing and spectrum sharing, Vodafone is open to reconciling the interests of satellite and wireless ISPs; however, he said that spectrum sharing could become complicated, slow down progress, and be a "massive drag" on the economy, on productivity, and on efficiency.
"We are developing models for collaborating with the regional ISPs," Lloyd added.
For its own part, the ACMA said that while it had attempted to come up with a spectrum-sharing model, it was unable to find a solution that would please both incumbent users and prospective users of the band.
"Unfortunately, we just couldn't come up with a sharing model that delivered what was necessary in this case. Having said that, if a sharing model was put to us and someone could tell us how to resolve it, we'd love to hear that. We think sharing and dynamic spectrum access is the future."
Miller pointed out that Telstra is not only a mobile broadband provider; it also has several licences across the current 3.6GHz band, and therefore understands the impact reallocation will have on the incumbent users.
"We have some satellite earth station licences ... we have about nine licences in this band ... and we also have some point-to-point links as well, I think about seven of those, which we also need to manage," Miller said.
"So we are very aware of the impact on incumbents including ourselves, and there needs to be an appropriate process in place to manage that impact."
Miller said Telstra supports the ACMA's preferred option to auction the spectrum in metropolitan and regional areas, and to protect existing licences for a transition period to make alternative plans.
Summers said the seven-year transition period on offer is "far more generous than expected", but does not allow enough time for the incumbents to fully realise their investments in spectrum.
The ACMA's 3.6GHz consultation package, published last month, said: "The highest value use of the band has (or will soon) move to wide-area broadband deployments (notably fixed/mobile broadband) in metro and regional areas".
According to the ACMA, submissions on the first discussion paper were "strong and highly polarised", with satellite, mobile, and fixed-line operators all expressing an interest in using the spectrum band.
"The ACMA acknowledges the major impact reallocation could have on current incumbents' use of the spectrum," it said.
The ACMA is accepting comments until August 4, with issues open to comment including whether the 3.6GHz band should move to refarming for additional mobile broadband spectrum; whether other options for incumbent services should be considered; whether sharing arrangements should be considered; whether seven years is a suitable reallocation period for spectrum licences; and whether areas outside of major metro regions should have a longer reallocation period.
The ACMA also wants to know whether the current west coast earth station protection in Mingenew, WA, is suitable for long-term satellite service use; issues affecting the possible development of an east coast earth station protection zone; whether there should be more than one earth station protection zone on each coast; whether there should be a central Australia earth station protection zone; and what frequencies and areas should be reallocated.
The ACMA released its first discussion paper on the possibility of refarming the 3.6GHz spectrum band for enabling 5G mobile broadband last year.