StarHub is the second placed operator in Singapore, one of the most densely populated countries in the world. Mobile penetration in the market is just shy of 160 per cent and four operators (one of which, DNA Comms, is a small iDEN player) are battling in what is, figuratively and literally, a very tight space.

StarHub launched LTE service in refarmed 1800MHz spectrum during the third quarter of 2012 and, while the firm has not released recent subscriber numbers for the service, an estimate from Informa’s WCIS Plus put the number of LTE subscriptions at 1,750 for 1Q13.

Mock already has one eye on LTE Advanced and says that StarHub is keen to get as much spectrum in Singapore’s upcoming auction as possible with a view to implementing carrier aggregation solutions. The Singaporean Government has voiced plans for an auction sometime in the middle of 2013, which will see further 1800MHz spectrum and 2.5GHz spectrum made available to the market’s operators.

“We will try and get as much as we can and we will have to make sure we get spectrum in both bands so that, with aggregation later on, we are able to offer a better customer experience,” Mock says.

The firm’s GSM subscriptions are in reasonably steep decline, with Informa estimating the total at 556,300 for end March 2013, down from 701,600 for the same point in 2012. As in other markets, spectrum is a tight commodity, but the time is not yet right to run down the GSM network in order to harvest the spectrum, says Mok Pack Lum, StarHub’s CTO.

“We have not announced any dates for this,” he says, “and we are still monitoring the traffic. There are two categories of users that will continue to need GSM; the people who roam into Singapore from neighbouring countries and the foreign workers who tend to be either labourers or domestic workers and have GSM phones.”

Nonetheless, Mock says, StarHub is keen to migrate customers onto its 3G network. “GSM is still a significant portion of our voice traffic but we’re trying to see how we can move as many people as possible from 2G to 3G so we can free up more of the 1800MHz spectrum for our LTE offerings.”

Given the small size of the Singaporean market, roaming—both inbound and outbound—is a crucial revenue stream for local operators. But there is little urgency around provisioning roaming services for LTE, Mock says. “At this point we are not concerned about LTE roaming. We are talking to our partners about it and we are putting in our diameter infrastructure. But we think that 2G and 3G will remain the most significant source of roaming traffic,” he says.

He adds that StarHub is “engaging IPX providers” for roaming services but that the firm is also considering “other multilateral initiatives”. This may be a reference to South Korean operator SK Telecom, which has made clear its intention to act as an LTE roaming hub for the Asia Pacific region.

Mock is similarly relaxed about VoLTE. For early movers to VoLTE the principal driver has been the need to consolidate to a single network technology. But for StarHub the technology is most interesting for the opportunities it offers in terms of enhanced services, Mock says.

“We are doing some [VoLTE] trials but I don’t know when we will be offering it,” he says. “The question today is which handsets are available. But the ability to combine voice with other IP applications is the most important impetus for us and that is down the line,” he says.

StarHub’s more urgent priority is extending the reach of its LTE network—and in Singapore this isn’t always easy. There are many high rise buildings and “the biggest challenge,” Mock says, “is providing coverage up to the 50^th floor.” Meanwhile all public housing in Singapore must contain a reinforced concrete bomb shelter with very thick walls, which presents a unique penetration problem.

“We’re hoping that, as vendors come up with integrated solutions, hetergenous networks and small cells, it will help solve our problems,” Mock says. StarHub plans to have nationwide outdoor coverage by the end of this year, up from around 60 per cent today.

But LTE is not StarHub’s sole network challenge . There are still coverage obligations to meet for the 3G network—the Singaporean government announced in April that the market’s operators were required to achieve 99 per cent outdoor coverage and 85 per cent indoor coverage and StarHub is awaiting confirmation that it has hit this target. It is in the firm’s interests to do so as it should help encourage users to move across from the GSM network, Mock says.

LTE has been simpler to deploy than 3G, though. Mock says that the most challenging aspect of deployment that the operator faced was refarming the spectrum—a challenge that was mitigated by the fact that the same vendor, Nokia Siemens Networks, supplied both the GSM and LTE networks.

Dependence on vendors is a reality for all operators and Ericsson’s head of LTE recently suggested that single vendor environments will provide better results in heterogenous networks, so does Mock Pak Lum agree? “Without having done any direct tests in this area, I would think that this would be so. Having a single vendor could be a more efficient and elegant way of providing coverage,” he says.

The LTE Asia 2013 event takes place in Singapore, September 18 – 19. For more information click here.