Telstra eyes surety as LTE moves on microwave territory

Rival telcos reject spectrum prioritisation plan.

Telstra has downplayed concerns over the extent microwave link operators could use co-existence arrangements being considered for the 1800 MHz band to stunt LTE rollouts in regional and remote Australia.

The incumbent, which is by far the largest operator of microwave links in the 1800 MHz band, is backing a plan by the communications watchdog that would allow LTE services into the space, as long as they don't interfere with existing microwave links.

Telcos including Telstra are already deploying LTE networks in 1800 MHz spectrum, but only in metropolitan areas, not in regional and remote Australia.

The Australian Communications and Media Authority (ACMA) is consulting on a plan that would enable a type of apparatus license to be granted to run LTE services in regional and remote areas.

The challenge is determining what to do about the microwave links that sit in that spectrum.

With options on the table to clear the space of microwave services entirely, or to downgrade the regulatory importance of fixed links, operators with the most to lose are backing a more rigid option that would force prospective LTE licensees to coordinate with fixed link owners before they can be granted a license.

Those without large-scale microwave assets are backing plans that would instead force the fixed link operators out of the band if a co-existence agreement could not be struck.

Telstra is backing the more rigid option based on its experiences deploying the Next G network in the 850 MHz band, which it notes was also "encumbered by existing fixed link services".

"Telstra's experience from this [850 MHz] rollout suggests that coordination with existing fixed links is unlikely to be a major problem," the carrier noted in a submission (pdf).

"The links are normally well protected by their narrow beamwidth antennas (3-6 degrees for the most commonly used antennas at 1.8 GHz) and reasonable fade margins.

"The worst fades at 1.8 GHz are in the early hours of the morning. This is the time when fixed links would be most susceptible to interference but it also the time of day when few mobile devices are in use."

The telco added that its own undisclosed "research indicates that if new LTE base stations were planned to cover all of the main population centres in regional and remote Australia then coordination with existing fixed link licences would be required for less than approximately 30 percent of these stations".

Miner Rio Tinto is among those to criticise such an approach on the basis that it is likely to limit any chance of establishing 1800 MHz LTE services in regional and remote Australia.

All players competing for a slice of 1800 MHz spectrum in regional and remote Australia are backing ACMA proposals that either afford them, or their industry sector, the greatest priority to secure some of the valuable band.

Telstra branded at least two of the prioritisation options on the table as "discriminatory".

Rival Vodafone Hutchison Australia took that concept further by rejecting all of the ACMA's proposed assignment priorities, and coming up with its own, which noticeably affords Telstra little spectral allocation. (pdf)

Optus also rejected all of the ACMA's proposed assignment priorities for 1800 MHz spectrum, also coming up with its own "assignment allocation" plan. (pdf)