Convergence Conversation

The Digital Britain report outlined some good starting points for a Universal Service Commitment of 2 Mbps by 2012. This is one of several notes of how users inherent need for more connectivity can drive industry and policy makers to do more and will be used to argue for  some changes to the proposed Digital Dividend spectrum auctions in 2012.

The success of wifi routers in enhancing connectivity in our own homes and as an aid to help get our neighbours get connected has an unsung and heroic status in the Digital Britain story so far. It uses unlicensed radio spectrum. It is unlicensed (ie Gov cannot sell it) because the frequencies can be effected by emissions adjacent to Microwave ovens.  Despite this, its utility in connecting devices around the home and slightly beyond is immense.

Mobile phones and Mobile Broadband services work on similar but slightly lower frequencies. Radio signals can interfere or cancel one another out, thus the whole notion of licensing frequencies for a particular use was created. One such licensing event was the 2000 3G auction where 5 operators paid a total of £22.4bn (£1100 per UK household) to have the right to transmit and receive signals in particular frequencies. This mind numbingly large number was enough to re-wire all of Britain with fibre but that is another story. The government is planning to auction some more spectrum in 2012, the so called Digital Dividend spectrum and this releases more frequency space so more bandwidth and coverage is scheduled over the next decade.

At least three significant changes have occurred in the last decade which should re-shape the whole nature of how we think of how this spectrum is managed. It is worth noting that radio waves are just one part of the electromagnetic spectrum, an incredible physical phenomenon which includes visible light. The notion of a third party having exclusive use of a given bit of electromagnetic radiation, even in private properties will be tenuous and can only be sustained if proven to be efficient and a consensus holds to that effect. 

Although the 2000 auction heist generated a huge amount of revenue for the government, this did not translate into great Mobile Broadband services for the taxpayer, for whose benefit the spectrum is managed. The potential of 7-14Mbps gets translated into user experiences of 150Kbps – 1Mbps to 80% of the population or 50% of the geographic area. Another auction in 2012 and another decade and the user experience may get a 600Kbps to 3Mbps user experience from a potential of 40Mbps that the full use of the spectrum would permit. The method of allocating spectrum ensures the bit carrying capacity of the radio spectrum is not fully exploited. This has been recognised by the Mobile industry itself as it is taking steps to share network resources, masts, power and locations while others are going a step further and sharing antennas and base stations. However the gap between users expectations and an ability to deliver cheap and reliable high speed data transport and connectivity remains high. Continuing to manage spectrum as per the proposed 2012 auction direction to Ofcom,  guarantees a sub optimal use of the radio spectrum. But this need not be.

The second significant change is that circa 80% of the population have some Broadband connectivity in their homes delivered on Cable or Phone line. Although ADSL operators do not publish their planning rules, the amount of capacity per home is comparatively large and with the fiber options the capacity will be greater still. If the 5 Mobile operators combine their frequencies ( 3G Network - 2x10Mhz-2 sectors, 70% loaded, spectral efficiency 2bits per htz x 5 operators) – 140 Mbps is possible per cell,  to be shared amongst all connected users, if fully rolled out. That's not a big download capacity and capacity drops significantly as you get further away from the base station. Paying £1,100 per household for exclusive use of a radio frequency using a finite number of base stations (circa 50,000) means by definition the spectrum cannot be utilised efficiently.  In bit carrying terms the licence grants a permission to ration its usage,  or more correctly and more accurately,  it denies us broadband users permission to use that spectrum.  Once understood it a bit like denying me the right to breath air in my own home.

The final change is a device called a femtocell. It is looks like a wifi router and it is, but it is using the frequencies allocated to the Mobile operator. It plugs into your Broadband connection and it is a mini mobile base station. It uses local power (£12pa) and the users bandwidth across the internet to access the resources of the Mobile operator including delivery and receipt of calls. The femtocell includes about 30 years of improvements in radio technology particularly an ability to adapt its power and manage radio interference. Vodaphone offers a femtocell today and will even give it to you free if you spend more than £60pm and suffer poor reception. The latter is a niche use when it is noted that 70% of data transport from mobile networks is to devices in fixed locations, and 60% of voice calls are from fixed locations.  So the act of off loading the data early is means the remaning spectrum and Mobile cell capacity can be used by somebody else.

You used to think you could cancel your fixed line and buy a mobile service. Given the growth in data downloads it can be argued it is more efficient to use a Broadband connection in order to get the full potential from your mobile service. The advent of femtocells when combined with our broadband connection certainly challenges the current regulatory notion of fixed and mobile access and for that matter the notion of voice and data.  As a user it is becoming increasingly intuitive.  There is connectivity and data transport, and there are services period.

This is good news for users. By paying for a mini-base station (you next wifi router upgarde), I and the neighbours I allow to use my Femtocell can get the full bit carrying potential of the spectrum. I am making greater use of my broadband connectivity. I have an increased choice of voice services (fixed/Mobile/WifiVoip), and when put together I should at least be getting more service for the same money. I should also be creating some very efficient local connectivity options to help the digital divide in my area. I may not need it,  but this is a good justification for paying for a fibre upgrade. I am buying more and better connectivity and a means to converge services. It provides a justification for pushing fiber out further and earlier, and we can crack on with defining and improving a Universal Broadband obligation!

Where are we?

The proposed Digital Dividend spectrum auction for 2012 does not consider femtocells, even though users controlled femtocells could provide the most efficient use of spectrum, and a very efficient way of bring fixed and mobile data transport together.

The opportunity to converge services is there for the taking, and it permits a more efficient use of the radio spectrum and is another use for our broadband connectivity. It's win win for the user, perhaps that is the problem!  

Mobile operators are thinking like mobile operators. They will use femtocells to improve reception where it is poor for their network. Thus,  today the femtocell is a Vodaphone femtocell working to their radio frequency,  but it is in my home, using my power and my bandwidth.  Each operator is testing the same technology configured to work on their discrete network, networks where everything but the frequency is  and its my electromagnetic radiation, being shared and paid for by me. The femtocell does need to a multi-vendor femtocell. Am I expected to buy one for each of our mobile phones, which for historical and work reasons are with different operators?

Fixed line operators like BT, SKY and Talk Talk, do not have mobile licenses so have no means to get going. Virgin media being an MVNO could do something interesting if there network partners agreed.  There is no way of sustaining so many voice services.  I currently have PSTN,  VOIP(x3)  and Mobile (x3).  Using my broadband connection in this way suggests I can get a bit more out of my connectivity and reduce the number of voice accounts,  should I chose and use that money to may for improved connectivity.

It would be helpful if the proposed direction to Ofcom on the 2012 spectrum auction consultation run by BIS, includes a clause where any new licences included a clause which demanded the support of mulit-vendor supported femtocells.  It seems impractical to have single vendor femtocells, if the regulatory policy promotes multi-vendor mobile competition. Combining our Broadband connectivity with developments in radio technology suggests that the vision for Digital Britain should be one which improves our fixed and mobile experience by combining them rather legislating to keep them separate indefinitely. Spectrum auctions cannot deliver efficient use of spectrum, if efficient means converting the potential of 7MBps into a user experience of 150Kbps.  This is purely down to the physics of attentuation of radio signals.  The spectrum policy needs to be adjusted to permit those investing in the nations bit carrying capability, (users) to combine that capability with the electromagnetic spectrum in its immediate vicinity. By doing so, greater and higher speed access is facilitated for all. The suitably equipped Broadband user is in the best position to utilise the radio spectrum.

Given the advent of femtocells, it would seem appropriate that the right to use specific radio frequencies should be modified with an obligation to support a common industry approach to a wide scale deployment of this capability in customer premises equipment with the deployment of femtocell gateway functions hosted on the internet. The latter would need to include a deployment plan for customer premises equipment to optimise the use of the available spectrum amongst users.

There is gain for all parties in this arrangements.  Mobile coverage and the use of the radio spectrum is increased.  Mobile companies need fewer base stations,  but will need to provide gateways on the internet.  The alternative is for users to start using E-NUM derived services. Users have another reason to seek and pay for broadband upgrades.  The conditions for fixed mobile convergence are set.  Mobile users get better utilistation of their smartphones, and could use their domestic connectivity for efficient receipt of Mobile TV and Radio content,  something not possible from these antenas 1 or 2km away. 

I have not specified any spectrum,  as I sure there are plenty of radio engineers who will suggest refinements.  It is my attention to idea into the BIS consultation on the direction to Ofcom on the proposed spectrum auctions.  I would be more that happy to pay my 50p extra levy,  if my improved Broadband connectivity allows me to use my connectivity in this manner.  Perhaps the levy is also the tax I pay for using radio spectrum efficiently in and around my own home.

I would welcome comments especially from radio engineers.  Issues of interference maybe raised but the advances in radios and some simple process of having one every 3/5 housholds would transform our very bad experience of mobile broadband and create immense increase in connectivity. The radio emissions are less than my wifi connection.