Software Femtocells and Femtocell Reference Designs: what’s the difference?

Ubiquisys announced its Femto-Engine software femtocell last week. Since then I’ve had quite a few people ask me what’s the difference between a soft femtocell and a femtocell reference design.

A femtocell reference design, as is currently offered by a few companies, comprises some of the basic hardware and software components that make up a femtocell. What you get are the basic software stack components such as RRC, RANAP, GTP plus some generic bolt-ons such as a TR-069 client. On the hardware side you get a baseband and RF chip recommendation plus recommendations on some of the ancillary components needed. Well this is a basic starting point. Having developed and commercially deployed both consumer and enterprise femtocells we at Ubiquisys are very aware of how much work there is in the full realisation. Ask our competitors such as ip.access and Alcatel-Lucent and I’m sure they would hold the same view.

A femtocell reference design represents approx 10% of the work for a femtocell company to actually bring a commercially viable femtocell to market. What makes it even more significant is that the remaining 90% includes all the challenging and high value software that creates a commercial femtocell. Features such as Self Organising Network functionality, Radio Resource Management algorithms proven out in the real world, bespoke operator customisation, femtocell specific features for supplementary services and emergency calling, 3G handset and macro network integration/test (massive task), provisioning & management system integration, diagnostic tools, etc. The list is almost endless and as you can see does not mention RRC and RANAP.

The hardware is a container for the software, the key being cost-optimisation. This is why Ubiquisys provides a femtocell Hardware Blueprint to manufacturers best qualified to build these home and enterprise products.

A good analogy is in the creating of a magnificent building like the Sydney Opera House. The reference design equates to some of the bricks, mortar, glass, pipes and cables needed for the construction. These are all important but the challenge and ultimate success is in the architectural design and skilled craftsmanship that makes the building a reality.

I don’t want to give the impression that the components such as the baseband and RF chip sets and firmware are simple and easy to design and develop. Far from it - the silicon design complexity and firmware in a component like the baseband chip is very significant and requires skills and experience that are found in but a few companies such as Percello, picoChip, and Qualcomm.

In the UMTS world there have been 5 public commercial femtocell launches; SoftBank, StarHub, Vodafone UK, AT&T and SFR. It’s no co-incidence that not one of these has been built on a reference design; all are bespoke femtocells designed and built by experienced and skilled companies ip.access, (AT&T) Alcatel-Lucent (VF UK), Huawei (StarHub) and Ubiquisys (SoftBank and SFR).

Unstrung: France Fires Up Femtocells

"French mobile operator SFR launched a 3G femtocell service today using petit base stations from Ubiquisys" writes Michelle Donegan in Unstrung.

It was great to see such a professional launch, especially when it is combined with a variety of price plans for SFR customers.

And the promotional video adds a new twist to the benefits of femtocells....

Location, GPS and femtocells: the global perspective

In his “Do you know where your femtocell is?” commentary on AT&T’s 3G Microcell rollout, Paul Callahan says that “GPS is fast becoming a requirement for femtocells” (Airvana FemtoHub, Oct 6). That’s certainly true in the US market, but the global picture is very different.

For CDMA networks GPS is part of the system - it’s a pre-requisite. But one of the key reasons why CDMA failed to take off across the world was its reliance on GPS, which is owned and controlled by the US Government. For UMTS, the 3G network choice of most operators around the world, GPS is not required.

With femtocells, operators need to meet national location regulations for emergency calling. Customers want to know that their emergency call will result in an accurate response. And several operators have told me that they see a robust emergency location system as a moral obligation, not just a regulatory one.

In reality there are many ways that a femtocell’s location can be determined. These provide different levels of granularity, complexity for the consumer, device cost and probability of success. There are pros and cons for each method which I’ll cover on another day.

Location determination methods employed by femtocells:

• GPS
• 3G and 2G Network Listen Mode: where the femtocells listen to surrounding macro cells and determine their location based on the location of these cells.
• Using the Broadband Access Database – where available (market by market) this allows a location lookup based on IP Address.
• Customer Declaration – currently used in European femtocell deployments to supplement Network Listen, where the customer takes responsibility for registering the installation address.

Operators are selecting the right mix of location methods to meet the needs of their markets. The best answer for femtocell vendors is therefore to offer both GPS and non-GPS options for location. And coming back to AT&T’s UMTS femtocells – GPS is definitely the right answer.

3G Femtocells: Who Makes What?

It’s great to see AT&T start marketing their 3G (WCDMA) femtocell, the 3G Microcell. Unlike the 2G femto offerings from Sprint and Verizon in the US, this not only promises a premium voice experience but also full speed 24/7 mobile broadband.

Following the launches from SoftBank, StarHub and Vodafone, the AT&T Microcell is a clear signal that the femto market is taking off across the world.

And on the face of it, there are around 20 3G femto vendors competing to supply operators with 3G femtocells. But that’s only half the story.

Firstly, you can’t always go by the brand you see on the box. For example, the AT&T Microcell is supplied by Cisco, but the femtocell inside the Cisco device was developed by picocell/femtocell developer ip.Access.

Secondly, the only true measure of a femtocell product in this hyped-up market is a commercial launch. Taking this measure, there are only four 3G femtocell vendors in the market today (in alphabetical order):
- Alcatel-Lucent at Vodafone, UK
- Huawei at StarHub , Singapore
- Ip.Access at AT&T, USA
- Ubiquisys at SoftBank, Japan.

There are some interesting similarities here. All of these companies have been doing intensive femtocell development for at least 3 years, and all have been working with their operator customers for at least two years. They also have in common 3G Radio Access and Core Network expertise as well as significant knowledge and experience working with mobile handsets.

This expertise is vital, because femtocells are extensions of the Carrier’s Macro Network. They are an integral part of a highly complex, high-reliability carrier-grade network with all that brings in terms of capabilities, features, network IOT, management systems, handset IOT and cognitive radio functions. The result is a software system that presents an extremely high barrier to market entry for any prospective femtocell vendor, which is why there are so few in reality. It is also a reason why no femtocell reference design has ever made it to market, despite having being around for years.

But femtocells are also consumer products, and they have to meet the demanding volume and price points of this industry. This is a well trodden path by home gateway manufacturers and the component companies that supply them – it just takes time.

There are other 3G femtocells under development, but today it’s all about four industry pioneers.

IMS femtocells: the basis for a new generation of IP-PBX?

Next Generation Networks (NGNs) featuring IP Multimedia Subsystem (IMS) architectures have been steadily taking shape at many operators over several years. The justification and suitability of IMS, particularly for mobile operators, is still hotly debated.

The simple reason for the debate is that everyone agrees the business case has to work, but every operator is starting from a different point with a different set of objectives. So IMS can be seen as a moving target but it is increasingly being deployed, particularly with LTE edging towards reality. The following discussion is not intended to debate IMS’s pedigree but more to consider what benefit it brings to femtocell deployments and why IMS femtocells are an increasingly hot topic.

Most 3G femtocell deployments, either launched or pre-commercial, involve some sort of integration with the legacy core network using a femtocell gateway, which essentially treats femtocells as multiple base stations. This approach has been standardised to a large extent with the 3GPP’s Iuh interface, which will eventually allow any femtocell to work with any gateway.

The potential of IMS femtocells
But femtocells are not base stations. In homes and businesses, they are IP devices that sit on a LAN, and are therefore peers of a diverse range of other IP devices, such as home media servers and office IP-PBXs. Interaction between phones and other IP devices on the LAN is one of the major attractions of femtocells. But legacy networks were not designed to deal with serving media from the edge of the network, and although this can certainly be achieved, the solutions tend to be proprietary and single-service based rather than providing a set of standard-based compatible ingredients that can be mixed-and-matched in innovative ways.

Putting an IMS client inside a femtocell opens up new opportunities for local media interaction. Because in IMS signalling and media delivery are handled separately, the core network can stay in control without having to handle the media, whose control is delegated to the femtocell. Of course the IMS client is only a small part of what is needed to IMS-enable a femtocell. Whereas a legacy Iuh-based femtocell only needs a part of the UMTS stack to operate because the femtocell gateway runs part of the RNC function connecting into the core network, in the case of IMS a femtocell must terminate the whole call, effectively representing all RAN and core functions in a UMTS network.

So with the flexibility IMS brings it’s easy to see how this would work for say streaming video from a home media centre, but perhaps the single most exciting opportunity is in business, by using femtocells to integrate mobile phones into a company’s IP-PBX.

Benefits of femtocell & IP-PBX integration
Here the mobile phone becomes an extension of the company’s phone system, giving mobile users access to all the advanced IP-PBX features like a single corporate dial plan, single voicemail, abbreviated dialling and user hunting/follow service. Users can seamlessly switch between their mobile phone and their desk phone while making or receiving calls, and can be reached by a single number. What makes this possible is the IMS controlling the call and connecting the media directly between the femtocell and the in-office IP-PBX.

For operators, voice offload to an IP network reduces the burden on the network. It extends the ability to support more subscribers on the existing macro network infrastructure. It relieves the core network by routing calls locally. These cost savings can be passed to customers in the form of more competitive tariffs.

Femtocells as part of an IMS deployment
As I mentioned earlier, most IMS deployments today are being rolled out alongside legacy networks. That is typically reflected in the phone population too, which comprises a mix of IMS-enabled and legacy devices. This can be a frustration for operators who would like to offer IMS-based services to all of their customers. Femtocells can help. Legacy phones connected to a femtocell can make use of its IMS client to access previously unavailable IMS services.

Note: this is an often misunderstood part of IMS-connected UMTS femtocells. The mobile phones used with these femtocells are completely standard off-the-shelf models and do not need an IMS client.

The Worlds first UMTS femtocell deployment was announced by SoftBank Mobile last year using our Ubiquisys femtocell. They are now ahead of the curve, having decided to start from day one with IMS-supported UMTS femtocells rather than the Iuh based approaches. There is additional complexity and a different set of problems to solve when implementing an IMS-based solution compared to an Iuh-based one. However, SoftBank Mobile is now benefiting from the increased flexibility and new revenue generating opportunities that IMS brings to the mix.

I’m just as enthusiastic about IMS femtocells as I am about Iuh femtos connecting to legacy networks. That’s why at Ubiquisys we set out from the start to develop one femtocell that could handle both flavours. Iuh femtos will provide strong market adoption through many operators. IMS femtos will open new convergence application opportunities for homes and businesses.

The incredible shrinking femtocell?

Commercial femtocell launches in the US, in Japan and in the UK show that the market is really starting to take off. Others are in the pipeline. This is significant for the femtocell industry as moving technologies from lab trials to launch is a well known hurdle that many don’t make it over. So the future for femtocells is looking pretty promising right now.

Coverage-challenged households and businesses are where the mobile operators have started with their femtocell offers. Many plan follow-on services to encourage the take-up of data services, homezone tariff packages, and bundles including broadband, IPTV etc. This will make femtocell adoption by consumers genuinely mainstream.

However, there are evolutions needed to achieve this and I believe they are taking place as I write.

The first is cost. Femtocells need to reach a price point so that mobile operators can offer the benefits of femtos with almost every service bundle and include them in every integrated access device or set-top box. Manufacturing in volume will help. Designing femtocells using the economics of the consumer electronics industry (rather than as network infrastructure) is essential, and has always been our approach to our stand-alone femtocells. Chip Integration and system optimisation through smart software also have a big part to play.

The second is form factor. Femtocells must be made smaller, they must run cooler and they must consume less electricity so that the integration into almost any home or enterprise device becomes technically optimised as well as meeting the cost needs mentioned above. This is happening today – as an example I’ve included a picture of one of our latest femtocell products, which is about the size of a credit card and uses just a few watts of power.

The physical characteristics are in the end a small but important part of creating a commercial femtocell. What enables this, and by far and away the most significant aspect, is the innovation, intellectual property and real deployment knowledge locked in the software. The Independent’s Sean O'Grady yesterday reported on Ubiquisys’ inclusion in the UK Government’s Advanced Manufacturing paper. He hit the nail on the head - “Their value lies not in the assembly of a few bits of plastic and metal, but again in that embedded intellectual value.”

Femtocell Industry Awards 2009: NEC and SoftBank recognised, Ubiquisys the Common Factor

My warmest congratulations at the Femtocell Industry Awards last week went out to NEC and SoftBank, mainly because both are part of an ecosystem that relies on Ubiquisys femtocells.

NEC won the award for Progress in Commercial Deployments. This recognised NEC's strong traction in the market. NEC has secured an impressive number of commercial contracts and has many live trials underway with operators around the world. All of these utilise Ubiquisys femtocells.

SoftBank won the award for Social Vision – the use of femtocells for social, economic or environmental development. Their Niimi project illustrates how femtocells can be cost-effectively deployed to deliver services in rural environments where existing coverage is limited. SoftBank's commercial deployment uses Ubiquisys femtocells supplied through NEC Japan.

Enterprise Femtocells: Easy to Underestimate

Enterprise femtocells, forming a grid of self-organising coverage, are genuinely new. So it’s not surprising that they are often misunderstood.

On one hand they offer the low cost and self-install simplicity of enterprise WiFi. Yet they also offer all the benefits of 3G cellular with massive data capacity. This is a heady combination, and promises to make in-building cellular affordable for small companies because the femtocells are based on mass-produced hardware, because no radio planning is required and because they can be self installed by the IT guys. They also promise to multiply the uptake of in-building cellular in large enterprises by providing added flexibility and simplicity at a fraction of the cost of today’s manually engineered pico/DAS systems.

John Spindler, in his article for Wireless Week, makes a couple of familiar assumptions about enterprise femtocells, which I’m happy to put right.

Assumption 1: minimum coverage overlap
The first assumption is that a grid of enterprise femtocells has minimal coverage overlaps. It doesn’t. In fact the femtos deliberately organise themselves into a grid with extensive overlaps.

Interference
What femtocells do that’s different to picocells is manage interference themselves in real-time rather than rely on the complex RF engineering that would otherwise be required. The femtocells obey the policies set by the mobile operators so will never produce unmanaged interference between each other or with the macro network. For example, femtocells in the grid use algorithms to ensure maximum spatial diversity between scrambling codes.

Signal dominance
Making the wrong assumption about coverage overlap leads to worrying about phones flip-flopping in and out of the macro network. But enterprise femtocells provide a strong indoor signal and also hold onto phones using “sticky cell” technology. Together these ensure that flip-flopping doesn’t happen, and that's true of any 3G phone.

Assumption 2: underestimating femtocell capability
The second assumption is that femtocells can support only a handful of calls and have a range which is a fraction of a picocell. Not quite: enterprise femtocells can range in capacity from 8-16+ users, and each one has a range approaching today’s picocells.

Handovers
Femtocells in the grid don’t need to do soft handovers because of strong cell overlap, and they don’t have to handover very often because their range is not far short of picocells. There is always a battery life penalty when handing-over, but this is more than offset by the massive reduction in handset transmit power. In any case additional battery consumption only occurs when on a call, not when the phone is moving but idle. So the net effect is a major boost in battery life over the macro network.

Over-provisioning?
In a grid of enterprise femtocells every femto handles not a handful of users but 8 or 16 or more - providing robust coverage and high capacity throughout the building. Most importantly, it does so more cost-effectively than Pico/DAS solutions that require radio engineers to deploy them.

Bottom line
Ever wondered why wifi access points tend to be installed in a modular fashion, rather than in a pico/DAS-style hierarchy? The answer is because they can be – it’s simpler, easier and cheaper. And the same is true of enterprise femtocells.

New Femtocell Reference Book

Femtocells are not just a new type of device, they change traditional technical boundaries and they open new commercial models for mobile.


There have been some good introductions to femtocells, such as David Chambers' Femtocell Primer, but what has been missing is a comprehensive reference covering both technology and commercial aspects in detail.


Enter the unambiguously-titled "Femtocells - Opportunities and Challenges for Business and Technology", available now for pre-order at Amazon.

The book examines the market, exploring commercial and technical factors which are critical in the initial deployment and long-term success of femtocells. Business, standards and regulatory aspects are also considered to provide a complete but concise overview.

• One of the first authoritative texts to concentrate on femtocells
• Written by expert authors from industry including leading analysts, femtocell and system vendors
• Covers both technology and business aspects in detail
• Provides overview of the relevant standards across WCDMA, LTE, CDMA, WiMAX and GSM air interfaces.

The authors of the book are all acknowledged femtocell experts, including Ubiquisys guru Andrea Giustina.

Femtocells - a network planning and management nightmare?

Kevin Fitchard asks some key questions about femtocells in his article in Telephony Online. He was commenting on how femtocells might be the answer to mobile networks reaching Shannon’s Limit of available capacity. Femtocells can easily provide the capacity relief, but with millions of them deployed, wouldn’t they “create a network planning and management nightmare”?

These are the challenges that faced femtocell pioneers from day one, and the solutions are fundamental to the femtocell concept.

1. How do you make femtocells self-installable under an existing macro network deployment deployed on the same spectrum?

This is addressed by the much talked-about principle of Self-Organising Networks. In reality, this means femtocells having autonomous cognitive radio capabilities that scan the relevant spectrum and optimise a complex set of parameters to work symbiotically with the macro network. It also means femtocells continuously monitoring the spectrum to adapt to any changes, such as a macro re-plan or the installation of a femto neighbour. This ensures that femtocells remain the adaptive subsidiary partners to the dominant manually-engineered macro network.

2. How do you enable millions of plug-and-play femtocells and keep them under control once they are out there?

The principle is to make the installation easy for the consumer and manageable for the Mobile Service Provider, and to do this in very large numbers. That’s why the DSL Forum approach for management (TR069) has been widely adopted for femtocells. TR069 is a proven method used to remotely manage millions of home gateways and set-top boxes around the world.

These two functions, fundamental to the femtocell concept and proven in real deployments, effectively eliminate the risk of nightmares.

Chameleon Points to the Future

Why did the announcement of Intrinsyc’s UX-Zone “chameleon” femto application generate so much interest? I think there are several reasons, and they point to the new ways we will use our mobile phones in the future:

• Touch-Screen Potential – Phones with large touch screens are a blank canvas for multiple experiences: home, mobile, work, retail, and so on. But until now it has been all about personalising one screen, not using multiple screens with different functions according to location. It’s a new way of thinking about interface design.

• Open Handset OS – The Android operating system from the Open Handset Alliance is specifically designed for complete customisation. Intrinsyc made full use of these features when developing UX-Zone, demonstrating the power of the original Google vision.

• Femtocell Automation – Clever features and endless options for customisation usually lead to complex products that most people don’t have time to learn or use. But femtocell presence triggers hide all of this complexity, making all location-based changes automatic. This leaves users with a simple , fun and useful experience rather than the fiddly apps that never make it beyond a narrow niche.

It’s amazing seeing it in real life. You feel like there’s a whole world of opportunities opening up in front of your eyes. Imagine this chameleon experience not just in the home; but also as you move between small “femto” cells in your everyday life, whether the office, stores, cafes, railway stations, airports, museums etc. The list is endless (well almost).

Femtocells for Business

This week I spoke at the Femtocells Asia conference in Tokyo on the subject of business femtocells.

Here are the main points:

• A grid of modular “Lego bricks” of coverage that can fit any business space and which can be easily expanded or remodelled

• Self-organising capabilities that eliminate the need for expensive RF planners to do site surveys or network engineers change the macro network to accommodate
  

• Simple enough to be sold through an operator’s existing direct and indirect channels.

It’s clear why picocells have had limited success to date. ABI Research senior analyst Aditya Kaul captured it: “One major reason for picocells’ low penetration has been their high total cost of ownership." Equipment costs are one aspect, but complexity of install has made deployment expensive and has limited the channels to market to the highly skilled.

How femtocell grids change this is by bringing complexity of install down to the level of WiFi, thus opening up the channels to market to include IT resellers as well as mail order self install.

There will always be the real high value enterprise customers where mobile operators will want to apply the personal touch and oversee the install themselves, but for the vast majority from SOHOs upwards a femtocell or femtocell grid, will enable, at last, new and compelling business packages to become available.

The Femto Forum meeting, also here in Tokyo, seems to be making good progress, and membership of the Forum continues growing almost weekly.

Commercial Femtocell Spotted at Tokyo Conference

I'm in Tokyo this week speaking at the Femtocells Asia conference.

When I arrived, mobile operator SoftBank had set up a display to demonstrate Ubiquisys-made femtocells working with a range of their mobile phones.

I took this (poor) picture because it captures an important moment.

Why? Because this femtocell is the real thing:

• It's a commercial femtocell, not a vendor prototype - a boxed product that ran off the Ubiquisys production line at Sony.

There are doubters here that UMTS femtocell systems are commercially ready. Well here's conformation that ours is at least, which probably comes from being the first to start.

My speech at the conference was about business femtocells, something I'm very passionate about. I'll let you know shortly how it went.

Ubiquisys Tops New ABI Research Femtocell Vendor Matrix Ranking

So for the third year running the highly respected analyst firm ABI Research has rated Ubiquisys as the number one femtocell vendor in the world. This year we are in first place for both dimensions of the study: Innovation and Implementation. Well known firms like Alcatel-Lucent, Huawei and Samsung were on the list, as were smaller companies like ip.access and Airvana.

This is not an accolade we take for granted, because we know that ABI does its research with mobile operators and with vendors very throughly, and uses a comprehensive and highly disciplined methodology. I've listed the categories that they analyse to give an insight into the breadth of the study.

Implementation
End-to-End Solution Capability and Ecosystem Partnerships
RFP, Trial, and Rollout Activity
Ability to Scale and Commoditize Quickly
Carrier Relationships
Overall Financial and Organizational Health
Silicon Strategy/Partnerships

Innovation
Cost
Interference Mitigation Techniques
Standards-Compliant Network Interface
Gateway IOT
Handset IOT
Solution Maturity
Hand In/Out
Module Support
Multimode Support
Future-proof Upgrade Path
Scalability
Femtozone Service/Application Framework Support
Support for Multiple Form Factors

We might not be seeing it in the press yet, but the UMTS femtocell market has fundamentally changed in 2009 as operators start their commercial launches. The focus on femtocells is now all about what I call deployment-ready. Simple for consumers, scalable, fit for purpose and operationally proven for operators, with effective interference management, the legacy handset issues dealt with (heads up guys - this one was non-trivial), and primed for consumer applications.

For a while now I have seen immature femtocell products hidden behind the reputations of their company names. In 2009 these vendors will have to stand behind their products for the first time. And remarkable deployment-ready products will get the recognition they deserve.

Femtocells in Asia

As many of you will be aware, late last year SoftBank Mobile was the world’s first operator to announce a mass-market commercial launch of 3G femtocells using our ZoneGate device and IMS infrastructure from NEC.

Asia is currently a hotbed of femtocell activity with Singapore’s Starhub also recently announcing a commercial pilot deployment and a number of other operators having advanced initiatives in the space.

Later this month I’ll be travelling to Japan for the Femtocells Asia Conference, where I will be presenting on The Business of Femtocells. It was announced earlier today that SoftBank will be demonstrating their commercial 3G femtocell at the conference using the Ubiquisys ZoneGate – the first public event of its kind to have femotcell enabled 3G coverage - so it’s set to be an exciting and informative show.

I’ll be blogging from my trip and will bring you details of my thoughts on the conference and the state of the femtocell industry in Asia.

Mobile World Congress: Insider view

I was so busy meeting Mobile Operators, partners and analysts in Barcelona that I didn’t get much of a chance to have a thorough look around. It has been fascinating however seeing all the marketing hype and Analyst views before and after the show. So I thought I’d give some down to earth views on common themes I experienced.

Real Femtocell deployment issues
There has been a clear change in emphasis amongst the more advanced Mobile Operators (i.e. those who have made the decision to deploy femtocells rather than those who are trying out technology) with a focus on the operational realities. Central to this are the laws of physics, i.e. the realities of radio interference. When you try out technology, or even do a launch for marketing purposes, you don’t mind sending engineering around to someone’s house. For the economics of femtocells to work, however, they must be plugged in by consumers not engineers. So when we laid out the original femtocell concept we planned not only to respect Mobile Operators and Consumers needs but also those of the laws of physics and how they are impacted by technological, material and regulatory realities. So I’ve been banging on about Ubiquisys using very sophisticated Cognitive Radio techniques for years in our Femtocells. Amongst other techniques we use unique methods that continuously monitor and adapting the radio parameters to the environment minimising interference, dead zones and abuse opportunities, and ensuring service continuity – and a happy customer. Why this is so essential is now understood by those Mobile Operators who have completed their technical due diligence for launch, and now being appreciated by those who are in the process.

Femtocells for Enterprise – definitely a hot topic
I had some great discussions with Service Providers and Enterprises on the use of Meshed Femtocells for Business (Not just SOHOs, which seems to be an established application these days, but using a grid of self-organising femtocells for much larger areas). I feel a bit guilty as the case is so compelling it doesn’t leave much room for the smaller picocells. We’ve been all the way with Mobile Operators; line for line comparisons of picocells verses meshed femtocell right to the finishing post – and meshed femtocell won – so we’ll be delivering it this year. Meshed femto will be a mix of different capacity femtocells to meet the needs of the business. It was good to see pretty much unanimous support for the concept. (Don’t get we wrong - Femtocells don’t remove the need for repeaters, picocells or DAS by any means.)

So are we any further forward from last MWC?
Yes definitely (but then you’d expect I would say that). There is always a hype curve with any worthwhile technology. Femtocell is one and therefore we expected there to be hype. The reality is the conversations have moved on massively from last year. The technology is in place for the commercial launches (at least in our case), we’ve manufactured 10s of thousands and there will be many femtocell launches this year and more next year across the world. That’s the reality.

Last year the discussions were about trials. This year it was about launches.

TDC in Denmark go public on their femtocell plans

For those who had wondered whether femtocells would ever happen, the proof is steadily emerging. We are finally begining to see the results of years of work in the background developing, testing and deploying the technology, and of course the creation of the service bundles that make it attractive to consumers.

The US has been a hot bed of Femto activity with Sprint and Verizon launching 2G bundles, and rumors of AT&T not far behind with a 3G solution. We also have had Softbank in Japan announcing their commercial launch this month (with our femto) and Starhub in Singapore. Now we have TDC in Denmark announcing their plans (again using the Ubiquisys femtocell).

The good news is there are many more to come so for me personnally having dedicated four and half years of my life to making both Ubiquisys and the Femtocell industry a success it's very satisfying. It also means I finally have mobile phone coverage at home.

How many calls can an enterprise femtocell support?

Well the answer to this question comes from the basic definition of a femtocell. It's an obvious answer but it's not necessarily an obvious path to get there.

A femtocell is a mass market device capable of being installed by the end user whether at home or in an office. So in an enterprise this could be the IT department, an IT reseller or one of the mobile operator's other sales channels.

This means that radio planning has to be automated (self-organising or cognitive radio). Assuming femtocells have to co-exist with existing macro networks that cannot be re-planned, what governs a femtocell's power output is the maximum interference the mobile operator will allow. This dictates the maximum power which in turn dictates a trade off between coverage and number of calls supported by each femtocell. Once you know what an enterprise's needs are (building type, coverage and type of business - call density), then it is simple to work out how many femtocells you need to cover the building(s) and what call capacity is needed for each.

So to meet any business's needs you need flexibility and that's why we came up with the concept of meshed femtocell networks. This can be made up of femtocells with various call capacities as needed. You can easily position them around a building so that coverage is guaranteed, as is handover and call capacity, at the lowest possible total cost.

What is an enterprise femtocell?

There has been a lot of debate recently about enterprise femtocells. What are they?

Are they the larger cousins of consumer femtocells, only with more users and more power? But how many users and how much power? Or are they standard consumer femtocells, arranged in a self-managing grid? But what is a standard consumer femtocell?

The problem is that this is a circular debate - there is no single answer, because the wrong questions are being asked. The fact is that the enterprise femtocell simply cannot be defined as a single device specification. Because no two enterprises are the same.

Instead, I think of Enterprise as an application of femtocells. What is important is meeting the individual enterprise's needs and giving mobile operators the flexibility to do this at the right price.

After all, femtocells come in all shapes and sizes, just like places of work. So it would be very efficient to deploy a mixture of 4, 8 and 16-call femtocells arranged in a grid. In other buildings single femotcells of various capacities might be best. I'll explain more another day.

Whatever their capacity, however they are arranged, they are all femtocells. Self-organising, self-managing, low-cost devices that businesses can install themselves.

That should be something we can all agree on.