Small cells remain a hot topic in the wireless industry, and this area of interest certainly got its share of attention at the recent Mobile World Congress (News - Alert). But while expectations remain high for small cells, and some major wireless service providers have made public their plans to deploy large numbers of these network elements, the extent to which small cells actually have been implemented to date is quite limited. And one source tells INTERNET TELEPHONY that femtocells, an indoor mostly residential version of small cells, have been less than a success for service providers.

Here’s the good news on the small cell front. The industry at large still seems bullish on small cells. AT&T (News - Alert) -- which has trialed small cells in Missouri, New York City and Wisconsin -- has publicly announced its plans to have 40,000 small cells operational by the end of 2015. Sprint is reportedly committed to large-scale small cell rollouts this year, although the company hasn’t said much about this lately. Verizon (News - Alert) has also expressed interest in small cells in the past. In fact, website AnandTech reports that Verizon at the CES trade show early this year was showing Alcatel-Lucent’s small cell and says “the Cube Dock 2600 will be deployed by Verizon starting 2H 2013 to do what amounts to hole filling in the operator's network. That is, deployment in small dead zones such as under a bridge or inside a mall that's still too small or under trafficked for a DAS (Distributed Antenna System) or urban environment.” And there’s a fair amount of small cell activity with carriers abroad as well.

About a year ago at Mobile World Congress, the mobile industry’s largest annual confab, was heavily focused on the subject of small cells and their important role in adding capacity and coverage to what people are referring to as the larger heterogeneous network, which is expected to be comprised of macrocells, small cells and Wi-Fi solutions. Small cells were again a center of discussion at Mobile World Congress earlier this year in Barcelona, but there was no blockbuster news on this front, there aren’t really any commercial small cell deployments to point to at this stage, and everybody is now familiar with the small cell concept so the buzz around this subject has died down to some extent.

However, just prior to Mobile World Congress in late February, ip.access announced that it’s shipped 1 million small cells. The company has been in the small cell industry for a decade, having started out with enterprise 2G solutions, then expanding to 3G residential applications, and now also addressing enterprise 3G and LTE deployments.

Also around the show, Informa Telecoms & Media issued its latest quarterly small-cell market status report for the Small Cell Forum, which the organizations say “highlights that public access small cells are gaining clear market traction and will dominate small cell revenues for the foreseeable future.” According to the report, small cells are poised to increase from today’s 11 million units to 92 million units in 2016.

Public access will be the predominant application for small cells going forward, according to the report, which says that by 2016 this chunk of the market will be worth $16.2 billion.

“Public access small cells in busy urban areas are set to be one of the defining mobile network trends in the coming years. While operators won’t be deploying them in the same numbers as femtocells, they are arguably their best tool for bringing massive extra capacity to their mobile networks. As this research shows, the vendors who succeed in this space are going to win the lion’s share of small cell revenues. All eyes will be on the deployments taking place in the coming months in order to establish best practice for the many more that will follow over the next few years,” said the report’s author, Dimitris Mavrakis, principal analyst at Informa Telecoms & Media.

In addition to AT&T’s activities on this front, Informa noted that Vodafone UK is testing 1,000 public small cells and plans to start rolling out tri-mode models (3G, 4G & Wi-Fi) by March, while Verizon expects to roll out the technology in the second half of the year. BT, meanwhile, is looking at how small cells might work to expand coverage to rural areas.

Informa and the Small Cell Forum also report that femtocells, of which there are 9.6 million in operation today, continue to progress. The organizations note that NTT DOCOMO is launching an LTE offering on this front; DOCOMO PACIFIC will deploy enterprise and residential small cells; and Orange (News - Alert) France and Vodafone UK are working with femtocells for in-building coverage.

However, while activities continue on the femtocell front, Raj Singh (News - Alert), general manager of the wireless broadband group and digital home and office division at Cavium, tells INTERNET TELEPHONY that there’s been “a bloodbath” on the femtocell front because those devices have not been successful in improving the customer experience.

Cavium was at this year’s Mobile World Congress talking about its small cell solution, which is in use by three Korean service providers. KT Telecom and LG U+ (announced this week) are using Cavium-embedded small cell solutions provided by CS, and SK Telecom is using a Cavium-enabled small cell solution supplied by Inno Wireless. Singh says that tens of thousands of these solutions have been shipped to these service providers, which began trials of the technology last August and started to use this gear in volume starting in December 2012.

Large populations in Korea use mobile services, creating significant service challenges for these providers. Some carriers have tried to address service availability by deploying femtocells, but Singh says it didn’t always work because early femtocell solutions sometimes lacked density and capacity. Cavium’s small cell solutions, however, apply macro technology and are based on category 4 transmission (which supports 150mbps downstream and 75mbps upstream) vs. category 3 transport (which is limited to 30mbps upstream), he says.

The definition of what an LTE small cell does is expanding, says Singh, explaining that some service providers are asking for small cell solutions that can support between 16 and 400 users.