SK Telecom's In-building 5G NR Repeaters and 'Layer Splitter'

In-building coverage is the new battleground in South Korea. According to this report by Korea Times back in August

SK Telecom, KT and LG Uplus, which have been in cutthroat competition to improve the quality of their fifth-generation (5G) network services, are now in a race to boost 5G data speeds inside buildings.

Their move comes amid growing complaints over disappointing 5G network coverage since the next-generation mobile network services were launched in early April.

SK Telecom said Wednesday it has completed the development of the "5GX In-building Solution" that is capable of doubling the speed of 5G data transfer inside buildings and effectively dispersing data traffic to prevent overload on base stations in crowded areas such as shopping malls and subway stations.

The nation's top mobile carrier said the new technology will be applied to its commercial 5G networks after the third quarter of the year.

"We expect 80 percent of data traffic to be from inside buildings in the 5G era," said Park Jong-kwan, who heads 5GX Labs at SK Telecom. "We will continue to give efforts to provide users with seamless, high-quality 5G services inside buildings and in crowded areas."

The company said its new system features "Active Antenna" technology that allows 5G small cells, which refer to small indoor base stations, to be equipped with eight transmission and reception antennas.

This will double the speed of 5G data transfer as existing indoor base stations are capable of operating four transmission and reception antennas.

KT has also been working hard to expand 5G coverage inside buildings.

In May, the nation's largest broadband service provider and second-largest mobile carrier interlocked 5G repeaters with commercial 5G networks in cooperation with small and medium business partners.

Installed inside buildings where radio waves from base stations can hardly reach, the device helps improve the quality of 5G services.

KT is in charge of expanding 5G coverage in 95 large buildings out of 119 nationwide, such as airports and KTX stations, in a joint project by the three mobile carriers.

LG Uplus, the smallest player, also has been active in installing repeaters in small and medium buildings and underground parking lots to expand 5G coverage.

The company is planning to expand the application of beam-forming and multi-user MIMO (multiple-input and multiple-output) technologies to its 5G networks nationwide.

Back in May, SK Telecom won SCF Small Cell Awards 2019 in the category of “Commercial Small Cell Design and Technology” for commercializing the world’s first 5G NR RF repeater. According to the press release:

SK Telecom won this year’s SCF Small Cell Awards for developing and commercializing, for the first time in the world, two different types of 5G NR RF repeaters operating in the 3.5GHz band in 2018. 5G RF repeaters, which amplify 5G radio signals to allow them to travel greater distances, are used to enhance 5G service quality by improving coverage for in-building areas.

SK Telecom’s RF repeater is built with 5G NR standard-based Time Division Duplex (TDD) Synchronization detection technology, which enables a more efficient use of limited frequency resources. In addition, the 5G repeater provides wide bandwidth support and operational optimization features.

Going back to the Small Cells World back in May, SK Telecom presented their solution but the presentation was not shared. Here are some relevant pictures from their presentation:

SK Telecom: will use various inbuilding solutions to complete 5G network. e.g. A 3.5GHz RF repeater to extend home/small building coverage - running remote antennas from the repeater.

— TheMobileNetwork (@TMNmag) May 21, 2019

Source: Phil Kendall

As can be seen in the picture (click to enlarge), depending on the use case and location, the InBuilding solution would change from Small cells to AAU and Repeaters.

Source: Dean Bubley

As you can see in the picture above, the 3.5/28 GHz layer split solution improves capacity of the building by creating multiple layers to improve the capacity. There is a new press release on this topic, which is covered in the post later on.

Source: Dean Bubley

The Speed Repeater above and the RF Repeater below is backhauling on the existing macro, similar to the In-band backhauling (IBBH) I have described earlier or Sprint/Airspan MagicBox.

Source: Dean Bubley

In a recent press release, SK Telecom announced that they have expanded the 'Layer Splitter', a dedicated equipment for 5G inbuildings, to 1,000 buildings, starting with WeWork Seolleung Branch (Gangnam-gu, Seoul). SK Telecom customers will be able to use 5G services twice as fast as existing in-building equipment in major domestic buildings such as shopping malls and department stores.

'Layer Splitter' is the equipment based on '5GX In-building Solution' developed by SK Telecom in the world in August. If existing indoor equipment is equipped with two antennas for data transmission and reception, 'Layer Splitter' is a four-integrated antenna equipment that can process more data simultaneously in the same frequency band.

It also integrates several signal conversion devices * that go through for communications services. The integrated device is half the size of the device as before, and data transfer rates are faster with fewer signal conversion steps. In addition, the integrated device is placed forward in the base station and only the antenna is installed inside the building, enabling quick action in the event of a problem without visiting the building.

※ Previously, it had to go through four-step signal conversion (digital signal → optical signal → base signal (IF) → optical signal → wireless signal (RF)), but 'layer splitter' Combined 'matcher' and 'donor', a device that converts the base signal (IF) into an optical signal

SK Telecom plans to expand in-building coverage centered on 'layer splitters' in buildings with a large number of floating populations such as large shopping malls and department stores. 

Wework, the first construction site, is a shared office where several ICT-related companies collaborate and expect various business models based on Korea's best 5G infrastructure. In particular, SK Telecom and Wework have been working together since last year's strategic partnership, including building 5G infrastructure.

Chang-Kwon Chung, head of infrastructure engineering group at SK Telecom, said, SKT customers can experience differentiated communication quality with the only equipment dedicated to 5G in-building. “In-building will be able to efficiently accommodate in-building traffic that will continue to increase in the 5G era. "We will continue to advance our proprietary solutions."

Hopefully we will learn more about this solution in near future.


Related Posts:

• SK Telecom's 5G Strategy and Services
• 5G+ Strategy of the Republic of Korea 

Small Cell Forum Releases 5G FAPI API Specifications

SCF has announced the release of 5G FAPI: PHY API Specifications. In the press release titled 'Small Cell Forum Publishes Specification to Drive Unified 5G Open RAN', SCF announced:

5G FAPI Release provides common APIs to support interoperability between 5G small cell hardware components and software layers enabling interoperability and preventing fragmentation.

Small Cell Forum (SCF), the telecoms organization making mobile infrastructure solutions available to all, has published the PHY API for 5G to stimulate a competitive ecosystem for vendors of 5G small cell hardware, software and equipment. The PHY API provides an open and interoperable interface between the physical layer and the MAC layer. 3G and LTE versions are already used in most small cells today.

The specification has been developed through a successful collaboration of companies from across the small cell eco-system, including; Intel, Qualcomm Technologies, Inc., Airspan Networks and Picocom Technology.

5G FAPI is an initiative within the small cell industry to encourage competition and innovation among suppliers of platform hardware, platform software and application software by providing a common API around which suppliers of each component can compete. By doing this, SCF provides an interchangeability of parts ensuring that the system vendors can take advantage of the latest innovations in silicon and software with minimum barriers to entry, and the least amount of custom re-engineering.

Operators are looking for a radically different cost model for 5G networks, one that relies on interoperability and an open, competitive ecosystem. As networks are disaggregated, a critical interface is the fronthaul between a distributed unit (DU) for radio functions and a centralised unit (CU) for protocol stacks and baseband functions. Open specifications such as SCF’s FAPI will enable operators to mix and match protocol stacks, basebands and radios from different vendors, and realize the benefits of deploying disaggregated, virtualized RAN (vRAN) networks.

The Forum also maintains the widely adopted FAPI specifications for 3G and LTE, as well as networked FAPI (nFAPI) for LTE supporting a MAC/PHY functional split, a key enabler for virtualisation of higher layer base station functions. In 5G this split point was also identified by 3GPP and called split option 6.

The Forum’s motivation for defining nFAPI in LTE was to establish a scalable ecosystem with a converged approach to virtualization across multiple suppliers, and the continued adoption of NFV/SDN make this is even more crucial for 5G. As such, the Forum plans to expand 5G FAPI to operate across split option 6 as 5G nFAPI.

A video of presentation by Clare Somerville, Intel & 5G FAPI lead from Small Cells World is embedded below:


In an interview in The Mobile Network last December, Prabhakar Chitrapu, who chairs SCF’s TECH Group said:

“Split RAN/Small Cell architectures have seven options, as identified by 3GPP. Of these, 3GPP has focused on Option-2 (RLC-PDCP) and ORAN on Option-7.2 (PHY-PHY). Option-6 (PHY-MAC) is not being addressed by any of these organisations. SCF seeks to fill this gap.”

“The PHY-MAC interface is important for the industry because it is an interface that has been highly successful in the 4G world, where it is called FAPI and nFAPI. It is therefore considered very important that we extend these interface specifications for 5G, as 5G-FAPI and 5G-nFAPI."

“FAPI helps Equipment Vendors to mix PHY & MAC Software from different suppliers via this open FAPI interface. So, FAPI is an 'internal' interface.”

“5G-nFAPI (network FAPI) is a 'network' interface and is between a Distributed Unit and Centralised Unit  of a Split RAN/Small Cell network solution. An open specification of this interface (nFAPI) will help network architects by allowing them to mix distributed and central units from different vendors.”

ShareTechNote also provides some details about FAPI and nFAPI as described by Small Cell Forim here.

Related Documents from SCF:

• SCF082.09.05: nFAPI and FAPI specifications
• 5G PHY API and Networked PHY API
• What is FAPI all about?

CrowdCell heads for TIP

Recently I wrote about Facebook's Telecom Infra Project (TIP) here. The following is from a recent announcement coinciding with MWC:

In our existing project groups, there are numerous TIP technologies that are moving from the lab stage to field and production trials. Each trial has operator sponsorship and includes key members of our technology ecosystem. Together, these TIP teams are working to validate technologies, share learnings, and accelerate toward commercialization at scale. Simultaneously, TIP members are contributing designs and specifications for new technologies and building new network tools.

Our TIP community is also growing and expanding in scope to address new challenges. Over the last month, TIP has added three new project groups and subgroups: Crowd Cell, Power and Connectivity, and Disaggregated Cell Site Gateways. At MWC, we are also announcing a new TIP community lab near BT’s Adastral Park campus in the UK and more than €100 million in venture capital funding available for infrastructure-focused startups participating in the TIP Ecosystem Acceleration Center (TEAC) in Germany.

In addition, we are excited to welcome some of TIP’s newest members: China Unicom, Sprint, and Telenor. They join more than 500 companies around the world that are active within TIP.
...

Crowd Cell is a new project group led by Vodafone. Crowd Cell is a concept based on relay architecture to help extend the range of existing cellular networks. Due to its plug-and-play design, Crowd Cell can be a rapid and low-cost small cell solution for traditional 4G networks. This project will focus on creating a Crowd Cell by leveraging generic hardware and open source designs for software to minimize costs through this “one design” flexible platform.
...

I blogged about the CrowdCell concept back in 2016 here. Then there were updates on the CrowdCell at MWC 2017 which I blogged here. This year, as the TIP announcement says, Vodafone is taking the CrowdCell to Telecom Infra Project. The following is from Vodafone's announcement:

Vodafone is developing new technologies designed to enable the cost-effective deployment of base stations in currently unconnected areas of Africa and India. The deployment will be supported by Vodafone’s new Open RAN technology and Facebook’s OpenCellular wireless access platform, which were developed within the Telecom Infra Project (TIP).

Open RAN technology significantly reduces the costs of rolling out networks in rural areas, fundamentally improving the economics of providing data and voice services to millions of unconnected people.  This new approach is expected to reduce the cost of radio network equipment by up to a third.

Vodafone also believes Open RAN technology will jump-start the establishment of an end-to-end industry of software and hardware vendors and integrators that will drive innovation, which is critical for achieving such a complex endeavour.

Picture Source: Michael Thelen

Vodafone has already conducted successful trials in India with two new vendors that have developed bespoke high-power base stations using software-defined radio and general purpose hardware based on Vodafone’s specifications and support. Wider scale trials are planned for later in 2018 where up to 200 sites will be equipped with the new technology. Tests are also currently ongoing in South Africa with TIP´s OpenCellular platform for 2G and 4G services.

This OpenCellular technology is being showcased at Vodafone’s booth at Mobile World Congress 2018.

Vodafone joined the TIP board in November 2017 and is a founding member and co-chair of TIP’s Open RAN project group, which aims to develop fully programmable RAN solutions based on general purpose processing hardware and disaggregated software. TIP is an engineering-focused initiative driven by operators, suppliers, integrators and startups to disaggregate the traditional network deployment approach.

The acceleration and expansion of this collaborative trend – embodied by TIP – will lead to significant change in the telecom industry and provide the ability to connect millions of people in rural communities for the first time.

Other TIP initiatives in which Vodafone is playing a major role include:

• Vodafone is leading a TIP working group to develop a new, open version of CrowdCell. The award-winning CrowdCell technology – developed by Vodafone’s Networks Centre of Excellence in Madrid – makes networks more “localised” to deliver faster download speeds and enhance the network’s reliability. For more information: http://www.vodafone.com/content/index/what/technology-blog/crowdcell.html
• Beyond radio, Vodafone and TIP are working together with Cumulus, Zeetta Networks and the University of Bristol’s High Performance Networks Group on evolving Voyager, the industry’s first white-box transponder and routing solution. Vodafone will demonstrate Voyager’s capabilities in a trial in April.
• Vodafone is also founding a new TIP sub-group within the Open Optical & Packet Transport project group focused on transport on disaggregated cell site gateways. Similar to the gateways in radio, these would reduce the current vendor lock-in that operators face in transport networks. Cell site gateways will be also based on off-the-shelf hardware, open software and interfaces on a technology agnostic platform.

Here is a slide deck that I prepared and shared on 3G4G blog here. The part embedded below starts from Vodafone section.

Small Cells, Macrocells, Backhaul, Infrastructure and other connectivity solutions from #MWC18 from 3G4G

Happy to hear your views on TIP or Vodafone's CrowdCell announcement. Please add them as comments.

Ericsson's Invisible Sites: Urban Case Studies

Small Cell Forum recently hosted Densification Summit in Mumbai. There were lots of interesting talks which can be seen along with the post-event report on SCF page here.

Anyway, the presentation by Ericsson is embedded below.

Small Cells World Summit 2017 Summary

I realised that I never got round to writing a summary post for Small Cells World Summit 2017. In fact I was waiting for summaries for various publications before writing a post but there was much less coverage this year.

Having said that, there were reasonable number of operators and most major vendors present. Small cells have sort of gone mainstream from their niche as many operators are now talking of small cells for 5G (mainly higher frequencies).

Anyway, here are some links with what I found interesting that you can explore further.

Here are some things ThinkSmallCell reported. Full report here:

SCWS, now in its 9th year, remains a regular feature of the small cell calendar. Now a two day conference, attendance was lower than some years ago but stable with noticeably more system integrators/installers actively participating. There was a little more focus on business enablers rather than technology this year, addressing deployment issues and neutral host opportunities for enterprise, urban and rural sectors.
...
The scope of SCWS is intended to embrace all of Small Cells, DAS and (Public Access) Wi-Fi. We saw one or two more DAS vendors participate but there was relatively little public Wi-Fi content. Perhaps that reflects the limited interest for that in Europe, as we saw at the recent Wireless Broadband Congress. The program included a few keynote speakers from operators (EE, O2, ATT, KDDI, Softbank) and some industry verticals (AEG, which operates the O2 dome and other stadiums; Grange Hotels etc.)       

Many mature small cell products are available today for both 3G and LTE. Form factors continue to shrink, software is becoming further automated and refined. The backhaul conference stream has been dropped with CCS now the most prominent independent small cell backhaul vendor.
...
The event provides an excellent opportunity to meet and reconnect with industry players, both old and new. The emphasis and participation has evolved over the years, but it remains a key focal point to assess the current state of play for the industry.

Here are some things The Mobile Network reported. Full report here:

The day before the Summit started Nokia assembled a few journalists in a meeting room and gave them a portfolio update. Of note in this was the revelation that the company will be shipping tens of thousands, in fact more than 50 thousand, of its Mini Macro cell sites to Sprint. This is on top of another wide scale roll out of the boxes – which are 2x20W sites in a 5 litre box – in China and Japan where the vendor expects to ship another 40,000. There are 3,000 headed to Brazil, as well, to be deployed as an underlay under Ericsson macro cells.
...
One notable aspect of the event was the amount of talk about using small cells in rural, in dense indoor and in other hard to reach areas. Mansoor Hanif spoke of some of the work BT is looking at to enable it to spread coverage to hard to reach areas. There is a real range of work, best summed up in this picture.

Of note is its work with TIP, where it hopes to be able to plug in open base stations as part of its Kuha community-run small cells programme – as per its project on the island of Harris supported by Nokia at the moment. With Lime Microsystems it is delivering a software defined radio base to Open Source, and hopes to attract developers to build applications on top of the Lime SDR platform. Hanif wants to move the cycle for introducing a new feature into a network from months to weeks – but he added that he doesn’t think any operator has the skills to manage that internally – hence the move to Open Source.
...
KDDI’s Fumio Watanabe presented some findings from the operators trials of mobile mmWave systems. The operator’s field trial use 40GHz and 60GHz bands, with a user moving between different bands and being “handed over” between access points. This sort of mobility requires dual interband connectivity and multi-site CoMP to handle the mobility between different sites and bands as a user goes out of line of site of an access point.

It may also require some architecture shifts Watanabe said, including the likes of ICN and MEC.
...
Backhaul provider CCS has a couple of things going on. First, it is involved as the backhaul provider to Telefonica O2’s deployment of outdoor WiFi and cellular small cells in the City of London. Steve Greaves, CEO, said that the company will support 450 small cells and 150 WiFi access points by siting its backhaul nodes at 30 Virgin media fibre points – with each backhaul node supporting 3-5 WiFi access points. The backhaul nodes are providing 1.2Gbps capacities at 24/26/28 GHz bands.

Greaves is also enthused by an upcoming product launch from CCS, as the company enters the 60GHz band with a 10Gbps product. Greaves says that CCS will go beyond products from the likes of Siklu, by modifying the basic WiGig chip that providers currently use, to add tighter carrier grade SynchE 1588, and greater interference control. The product will not be available until early 2018, he added.

Another interesting aspect of the City of London deployment – the concession model between the City of London and Telefonica – means that Telefonica must host other operators’ small cells within the deployment if asked. But these may not be on the same pole as Telefonica’s small cells, given there is a limit of two boxes per pole. From a backhaul perspective – that obviously introduces more complexity – as Telefonica must introduce a V-LAN for each operator, with different QoS.

Virgin Media Business, by the way, has 100,000 cabinets in London alone, and wants to use them to act as potential hosts for small cells, by adding a small pole to the cabinet, said its adviser Paul Coffey. The company is also looking at enabling neutral host model using its street infrastructure. Its wholesale business supplying backhaul to the UK’s operators already runs to £150 million per year, Coffey said.

Related Posts:

• Nokia Kuha: Community-run Small Cells
• Small Cell Forum Awards 2017 Winners
• Telecoms Infrastructure Blog: Flying Small Cells are here...
• Drone cells are becoming a reality 

SDN and Distributed NFV for Small Cell Mobile Backhaul

An interesting presentation on how Distributed NFV can be used for Small Cell backhaul. The calculations show that 80% TCO savings. The presentation is embedded below and the video is available for viewing here.

Case Study: Fastback IBR Small Cell Backhaul Usage Scenarios

An interesting presentation from the recent Small Cells World Summit 2014 (kindly shared by Lance Hiley of Fastback Networks). The first part is a trial by Virgin Media and the later part is the case study by Fastback networks where they used their Intelligent Backhaul Radio and reduced the number links required to obtain similar performance as compared to a 'line of sight' solution. The presentation is embedded as follows

LOS, nLOS & NLOS: All-­In-­One Small Cell Backhaul For Cost-­Effective Delivery of SLAs from Zahid Ghadialy

Huawei's Lampsite

Huawei unveiled its 'Lampsite' for 'Deep Indoor Coverage' back in 2013. This is what they announced then:

LampSite includes a comprehensive set of BBU, RemoteHUB(rHUB) and PicoRRU(pRRU) products along with accompanying transmission solutions. The compact pRRU supports multiple bands and modes and can simultaneously support LTE TDD, LTE FDD, UMTS and GSM. A LampSite indoor coverage network can also be deployed simultaneously with Huawei’s SingleRAN solution. 

Thanks to BBU’s baseband sharing feature, one fiber is used for several cells, saving up to 87% of fiber typically used for indoor deployments. rHUB connects to pRRU by cable, and support power over Ethernet (PoE) to simplify site construction and reduce total deployment costs. 

In an early deployment phase, individual pRRU cells aggregate into one cell to reduce interference. Once the network offloads heavy traffic, the cells are split again and Adaptive SFN is enabled to balance capacity and interference. Huawei iManager system and evaluation tools are then used to accurately monitor and intelligently optimize indoor hotspot traffic.

This innovative solution has not only helped them to win contracts with China Unicom, TDC Denmark and Telenor Norway but according to TMN magazine article, "Huawei is shipping more than 10,000 PRRUs (Pico Remote Radio Units) per month in some countries and regions for its LampSite in-building system, according to Peter Zhou, Huawei's President of Small Cell & WiFi, Wireless Network."

Recently Huawei and Telenor also won an award in the LTE World Summit for "Innovation in HetNet Development". With Huawei’s LampSite, Telenor is able to provide average downlink throughput of 46Mbps at any location in a building and significantly cut costs. Deployment of each pico Remote Radio Unit takes only three hours – from site survey, through installation, commissioning, to going live, ensuring rapid rollout in areas with weak signal penetration.

Based on presentations in different events, looks like Huawei is not complacent with its achievements. It plans to develop the next generation or NG Lampsite to achieve 1Gbps Indoor throughput with whole lot of technologies to help achieve this. Multi-stream Aggregation (MSA) being the key. See my earlier post on MSA on the 3G4G blog here.


Related Posts:

• Telecoms Infrastructure Blog: Huawei Lampsite 3.0
• Telecoms Infrastructure Blog: Small Cells and Neutral Host Networks
• Telecoms Infrastructure Blog: Huawei SkySite: Drone with 5G base station & '5G Book' RRU

Small Cells World Summit (#SCWS14) Video and Summary Articles

The Small Cells World Summit concluded last week. The main highlight was the Release 4 of Small Cell Forum on Urban, building on top of Release 3 - Urban foundations



Around 20 new documents have been published, available here on this release. Land Mobile has more details about this launch by Small Cell Forum here.

There were couple of interesting videos from the event by ThinkSmallCell and ConvergeDigest, they are embedded below:





Other related links (new links will be added as and when available):

• Airvana Is Back With a 'Cloud RAN' 4G Biz Cell - Light Reading
• Urban Jungle Is Still Too Wild for Small Cells - Light Reading
• Small Cell Forum Tackles Urban, Virtualization - Light Reading
• This is not the small cell you are looking for: why ip.access' presenceCell will make operators money by rejecting users - TMN Magazine
• Operators hoping for small cell "Sweet Spots" - Mobile Europe
• Mini cell towers: The end of crappy phone service - CNN
• SCWS: small cell sectors seeks diversity without fragmentation - Maravedis-Rethink
• Small Cells World Summit 2014 Event Report - ThinkSmallCell

China Mobile's Nanocell

China Mobile prefers to call its Small Cell, Nanocell. I found an interesting summary on this topic from Rupert Baines in the OSP Magazine, some of this information is copied below.

Nanocell is defined by the China Mobile Research Institute (CMRI) as follows: “An integrated Small cell supporting GSM / TD-SCDMA / TD-LTE standards and WLAN (WiFi) solutions. With the key feature of supporting both wireless network and WLAN (WiFi) services, it can be deployed in enterprise, home and high capacity hotspot locations. It also uses standard broadband connection as a low-cost network backhaul, hence reducing deployment and maintenance cost while providing advanced and reliable security features.”

Nanocells, provide mobile coverage to a limited area as well as integrating carrier grade WLAN access points. They are often used to add network capacity in areas with very dense data usage. In some respects they are the next iteration in small-cell evolution.

Although in theory a nanocell could have a range as large as 2km, in most situations it will be less than that: perhaps 100m-500m. As such, a nanocell allows for deployment in locations that are expected to handle more phone usage than usual, for example during a sporting event or concert.

In September 2012, in a pioneering program to develop China’s mobile infrastructure, Mindspeed, the manufacturer of semiconductors for small cell base stations, signed a memorandum of understanding with China Mobile Research Institute (CMRI) in Beijing to contribute to the rapid build-out of China Mobile’s heterogeneous network (HetNet).

A HetNet is constructed with layers of small and large cells including nanocells. These cells will be able to self-organize seamlessly providing a higher quality and consistent connection to the network for users. The aim of this collaboration is to accelerate the field trial of TD-LTE small cell systems across the China Mobile Communications Corporation’s (CMCC’s) network in China.

As noted, CMRI’s definition of nanocell could be described as “small cell 2.0”. There are various architectural enhancements, but 2 in particular are worth describing.

CMRI Enhancement #1 is the integration with Wi-Fi. Some people naively view small cells and Wi-Fi as competitors. But a more sensible approach is to combine them, to take advantage of economies (single power supply, shared backhaul, cheaper provision and OpEx) and to use synergies in the  bearers (for example, handing off traffic between the 2, taking advantage of the extra capacity
of Wi-Fi with the longer range and better QoS from cellular). The Small Cell Forum has been working on this, and it is a key part of CMRI’s nanocell.

CMRI Enhancement #2 is multi-mode. One aspect of a nanocell, which is important to most carriers, is supporting several cellular standards in one node. Much of the cost is per element (siting, installation, OAMP, power, backhaul) so it makes obvious sense to combine them to share those costs and make the best use of the spectrum.

China Mobile is unusual in its cellular technologies. In common with most of the world it has GSM as 2G, but for 3G it uses TD-SCDMA (standardized by 3GPP and a variant on the commoner WCDMA). For 4G, it uses LTE but the TDD flavor (TD-LTE). This is not yet widespread, although estimates are that between 20%-40% of all LTE will ultimately use it. The CMRI nanocell must support these technologies.

Things have progressed well and in the recent Small Cells World Summit 2013, CMRI showed their enterprise deployments that are being tested.

A presentation from the WiFi global congress is embedded below and gives more detailed idea about the Nanocell.

Introduction of Nanocell - China Mobile from Zahid Ghadialy

SK Telecom: Commercial deployment of LTE Femto cell

SK Telecom does not fail to impress with their aggressive roll-outs and impressive solutions to challenging problems. One such presentation from the Small Cells World Summit 2013 in London is embedded as follows:

Commercial deployment of lte femto cell with the innovative technologies and the roadmap from Zahid Ghadialy

Another presentation from late last year is available here.

Small Cell World Summit 2013: Video and Report

David Chambers, Think Small Cell, has compiled a quick summary of the recently concluded Small Cells World Summit which is worth reading and available here. A video made by him is embedded below: