Ofcom Small Scale DAB trial – Too Small?


Basic CMYKWith their latest announcement it is now official – the previous Ofcom Low-Cost DAB trial has seamlessly morphed into a “Small-Scale DAB” trial.   This is an important difference that will impact (negatively) on many radio stations’ commercial viability.

The key difference between FM and DAB is the concept of a DAB multiplex – which combines several stations that take a finite (roughly 7 times more, and no less) amount of radio spectrum more than a single stereo FM station – even if only one station is carried.  Put that the other way – in a “small scale” area we need 7 stations to fill the small-scale-DAB multiplex just to break-even with what is technically possible with FM. That’s fine as long as the rules of the DAB game  permit an adequate coverage area to capture 7 stations.  Yet Ofcom are imposing an arbitrary limit of 100w which in many situations is unlikely to encompass 7 commercially-viable radio stations.

Two respondents to their consultation expressed concern at the arbitrary 100w limit set in the document was not congruent with the parallel Ofcom requirement of:

  • 100w maximum effective radiated power
  • no larger than 40% of the local commercial DAB Mux area.

The latter seemed a reasonable compromise to protect the monopoly incumbents (if really necessary?), whilst the former is an arbitrary power limit that does not make sense compared to the second point (ie: the lower the power permitted the more the transmitters required = £cost).

The Ofcom response was “it is not necessarily the case that allowing a higher power will in all cases reduce the number of transmitters needed” – which answers a question which was not asked!  (hint – sometimes a power above 100w will reduce the number of transmitters needed!)

As far as we understand the DAB infrastructure in the UK is currently provided by a monopoly provider (Arqiva) – a company which claims an EBITDA (profit) margin of 51% – substantially higher than traditional regulator targets like mobile phone companies.  Say no more.

The original low-cost DAB concept trialled by Ofcom offered a potential route to break this monopoly and lower the cost of entry for a new tier of broadcasters.    Their offer to supply equipment for the trial is to be applauded.

Yet in parallel we have a trial licence that is likely to seamlessly morph into the permanent licence regime that handcuffs small broadcasters in a similar way to the current Community Radio Licences – Is it impertinent of us to ask why we have such arbitrary power limitations on this wonderful new concept?


DCMS Community Radio Consultation Response – Part 2


Well finally the DCMS have responded!  Up and down the country community radio station managers are celebrating the decision with magnums of Pol Roger champagne, while small commercial stations contemplate the rapid demise of their business…

We jest of course, but you’d be forgiven for believing us if you had read RadioCentre’s comments on Radio Today!

In reality it’s all a bit of a damp squib as we predicted in our post on Monday.   By DCMS’s own admission (in their Impact Assessment) it is actually a “Modest Change”.  You can see for yourself in their document and on other radio news websites.   Community radio currently has a 0.7% share of radio advertising in the UK (source Ofcom Communications Market report 2014). If all CR stations take 100% advantage of the new £15k advertising ability it will increase to around 1.4% – hardly earth shattering.   In reality though many community stations will use the new “disregard figure” to reduce the considerable time and effort they currently spend raising funds through non-radio means.

And it is also likely that community radio’s share of the radio advertising market is actually increasing the market size.  After all, how many big advertisers have you heard on your local community radio station?  The reality is that these small radio stations with 25watt transmitters run by part-time volunteers attract a different tier of advertisers who cannot afford to advertise on commercial stations.

So in effect today’s announcement from the DCMS is preserving the status quo and nudging it slightly in favour of the community stations.  In the Government’s mind there seems to be a clear divide between community radio and commercial radio, so they have sought to preserve the regulations that ensure no blurring of the lines.

There are a couple of interesting points buried on page 12 of the DCMS impact analysis:-

  1. Community stations will have to request (and pay to apply) to use the new DCMS rules: “where stations will want to take advantage of new conditions a small cost would be incurred by a station to meet Ofcom’s administrative and resource costs – to cover application form, guidance note, assessment and decision”
  2. Perhaps if community stations maintain the pressure there is scope to review the £15k “income disregard” limit over time without waiting for slow legislation: “the income disregard figure will fall to Ofcom to review, on an annual basis, to ensure it retains its worth and benefit to the community radio sector. It should be noted it will be possible for the income disregard figure to be adjusted either up down or to remain unchanged”

We wonder what the radio landscape could have looked like if the DCMS had recommended Option 4 in their Impact Assessment (and learned how to spell!) “4. Full deregulation – Not considered as it would turn community radio into commercial radio undermining wider policy goals. Option 2 is the prefered option.”   A renaissance in local commercial radio could be just the tonic that Radio in the UK needs!

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DCMS Community Radio Consultation Response


DCMS Department for Culture, Media and Sport logoGetting on for a year after it was published the DCMS Community Radio consultation response is finally about to be available.   On the cusp of its publication we thought we’d stick our necks out and review what’s at stake.  We reserve the right to update this post in the coming days!

Just in case you cannot remember, it asked for opinions on four key questions:

  1. The lifting of the restriction on community radio stations preventing them from taking any income from on-air advertising or sponsorship if they overlap with a commercial radio licence whose coverage area includes 150,000 adults or fewer.
  2. On the restrictions preventing community radio stations from taking more than 50% of their annual income from on-air advertising and sponsorship, if they remain appropriate, and what, if any changes, are justifiable.
  3. On the case for further licence extensions for community radio stations in the event of a decision to implement a radio switchover.
  4. On improving the effectiveness of the Community Radio Fund.

Associated Broadcast Consultants responded to the consultation last year.   Our response probably won’t win us many friends in the Commercial radio sector, but we like to believe it was considered and balanced:-

  1. Of course the advertising restrictions with overlapping small commercial stations should be scrapped.  Heck, if you are worried by the threat from a band of part-time volunteers running a not-for-profit venture, then actually you’ve got bigger things to worry about!   In any case, many of these so-called small stations are actually the local outlet for one of the semi-national radio brands like Heart or Breeze.   It’s akin to saying Oxfam aren’t allowed to sell clothes if there is already a Next shop on the High Street!
  2. Of course the 50% funding rule should be scrapped.   The main business of a Community Radio station should be producing good radio, not scratching about running cheese and wine parties, jumble sales etc to diversify funding away from advertising.  If this rule applied to newspapers then we wouldn’t have the Metro free newspaper to read on the way to work.
  3. Licence extensions – should be judged upon the merit/track record of the station and the scarcity (or not) of FM frequencies in the area
  4. Community Radio Fund is a dangerous distraction.  It risks breeding a dependency culture, and due to its lottery nature cannot be relied upon for stable business planning.  We suggested scrapping the fund and using the funds released to set-up a national advertising agency for the community stations.  Hopefully over time this would become self-funding.

It remains to be seen what the actual response will say in the coming days.  Our guess is that the incumbent broadcasters will win some concessions, but also they will throw a few changes in to try and keep the community radio broadcasters quiet, whilst also alluding to the potential of “Low Cost DAB”.


Raspberries, Steroids and Low Cost DAB


On the horizon there is a real possibility that digital radio broadcasting in the UK could become affordable….

TODROID-U3he picture on the right is of a small yet powerful Linux computer called the ODroid.  It was described yesterday by Martin James (Manager of Broadcast Radio) at Ofcom as “like a Raspberry Pi on steroids”.

It is smaller than a pack of playing cards, yet it is this hardware that they were using to demonstrate the potential of Low Cost DAB at Riverside House yesterday.   It seems incredible, but this diminutive device was being used to encode 6 audio streams into MP2 (the current codec of choice for DAB in the UK) and then multiplex them together into a DAB multiplex suitable to be fed to a Band III transmitter modulator.   Thus for around $65 plus some free open-source software it seems possible to produce a mux signal equivalent in many ways to that generated by professional DAB Mux equipment costing tens of thousands of pounds.

And it seemed pretty stable too.  Rashid Mustapha (low cost DAB guru at Ofcom) demonstrated the lack of impact by failing on of the programme streams (by pulling the plug!).  The other five streams on the Mux happily carried on – as demonstrated on a domestic DAB radio set alongside the demo equipment.

Of course more is needed to transmit DAB – not least a modulator (to turn the Mux bistream into a radio signal), an amplifier (to amplify!) a filter (to remove any sprogs generated in the amplification stage) and an antenna plus some kind of tall structure to mount it on.  All this does not come cheap, but then again, compared to the cost of carriage on existing commercial Mux’s, it is not expensive either.

Nor should we forget the cost of links – the important lines that get programme services from different stations to the little ODroid Mux box, and potentially a broad link from the output of the little Mux box up to the transmitter site.  Yet here too there are low cost alternatives to current approaches.  Trials indicate that the internet is stable enough for individual programme feeds.  And for the big link between Mux and transmitter there are affordable digital microwave links available.   Intruigingly also Ofcom hinted at the possibility of using on-channel repeaters.  This means the mux could be connected to a low power transmitter at a suitable host location (possibly one of the radio stations hosted on the Mux), and then this signal could be received, amplified and re-transmitted from a big hill giving wide area coverage.

Low cost DAB spectrum analyser

Spectrum Analyser showing the Low Cost DAB signal

There is still a long way to go.  The current stage is very much prototype.   The next stage is a trial next year for which Ofcom recently issued a consultation (see post below).

It will be interesting to see how this low-cost DAB concept develops, and how incumbent DAB Mux operators  will react.  Hopefully there is room in the UK Broadcast industry for both “Gold Plated” and “Low Cost” DAB.


Ofcom revises its invitation for applications for community radio services in the East of England


In a surprise move Ofcom today announced that it had revised its invitation for applications for community radio services in the East of England.

The change regards Southend-on-Sea where it had previously said there were no available FM frequencies for a new community radio service.  Apparently one of the main concerns was interference from a very high power transmitter in Lille, France, although potential applicants in the area say they have never noticed any French stations receivable on the FM dial in their area.

Funky SX logoThis is great news for (currently) internet-only station Funky SX who won £50,000 through ITV’s the People’s Millions to establish a youth-led urban and dance music radio station for Southend-on-Sea.


Ofcom consults on new short-term licences for small-scale DAB Trials


The wheels turn slow, but things seem to have started moving at Ofcom with regard to what they variously call either “Low-Cost DAB” or latterly “Small Scale DAB”.  One wonders if the new name is to pacify the incumbent DAB multiplex operators who surely must have been a bit jittery by the original “low cost” name?   Anyway Ofcom published today a consultation on  new short-term licences for small-scale DAB Trials.  Is that a trial of small-scale DAB, or a trial of DAB that is small in scale?   Generally the idea is to find a digital solution that addresses the needs to small-scale and community radio broadcasters in the UK.

Currently such broadcasters find it difficult to get on DAB due to the huge expense – resulting in a bizarre situation where there is demand, but many commercial Mux’s are running significantly below maximum capacity.  Cynics will say this is due to the lack of competition for DAB transmission services in the UK, although partly it is as a result of the structure of the DAB industry.   Also the technology requires a collection of radio services to be broadcast on one frequency instead of one service, one frequency like for FM.  Whilst this does not explain the expense (surely sharing transmission should reduce costs?), it does explain the need for “transmission middle-men” – the Mux operators.

The Ofcom trial, and others like the Total Broadcast DAB trial in Ireland have demonstrated that it is possible to provide DAB services for significantly lower cost that existing UK DAB Mux providers.

This consultation will give interested parties an opportunity to shape the future of DAB in the UK.  No doubt it will also give the DAB incumbents an opportunity to create obstacles to creating viable competition to their lucrative businesses!


CR station wins High Court battle to continue broadcasting


An interesting David & Goliath storey of how a CR station won a High Court battle to continue broadcasting here.   The judge Mr Justice Treacy said of the Ofcom decision:

“In my view it was unfair for the breach decision and the no extend decision to have been taken without conscientious engagement with the request for an oral hearing……I also consider that without such safeguards the decision is disproportionate.”

It will be interesting to see if this changes how other CR stations approach their key commitments, or how Ofcom deals with trangressions.


Ofcom invites applications for licences to provide community radio services in localities within the East of England


In a surprise move today, Ofcom  invited applications for licences to provide community radio services in localities within the East of England together with Northamptonshire and Milton Keynes.

It is not known if this tactic is an opportunistic way to bring more radio choice to the East of England a little earlier than expected, or a cynical way to further delay the invitations for London and the South East (originally planned “First half of 2014”).

What is obvious though is that Ofcom, maybe inspired by the recent Scottish referendum debate, has re-drawn the map of regions in Southern England compared to what it envisaged in the original Third Round licencing guidance.

Ofcom Community Radio Regioons Map - Eastern England

Ofcom has created a new Greater London region 10 (that should get people hot under the collar!) and the old Region 7 for London and South East now becomes Region 9 for South East minus London.   In fact this is not new – they did something similar when they invented a new West Midlands region for the invitation earlier this year.

What is less of a surprise is the usual Ofcom guidance notes for would-be applicants.  It reminds them of the limits on advertising.  It also advises on limits to frequency availability, but helpfully suggests that AM frequencies may (not will) be available.   Near the end it also lists some poor little commercial stations that need to be protected from the ravages of competition from Community Radio – entertainingly including Heart!

Full details available in the Ofcom Invitation of applications for community radio licences: EAST OF ENGLAND (WITH NORTHAMPTONSHIRE AND MILTON KEYNES)

Applications for community licences for these areas must be received by 5pm on 16 December 2014.  Associated Broadcast Consultants is expecting a busy time ahead – we advised a record number of applicants during the last invitation for the East and West Midlands.


“DAB is the Future” – so have another 12 years on your FM Licence!


Yesterday Ofcom published a statement detailing the extension of advertised or readvertised local commercial analogue radio licences from seven to 12 years – lending these stations a somewhat greater degree of certainty than Community Radio stations that only get 5 years at a time.

Implicitly they are saying the FM waveband will remain until at least 2026 and probably beyond.  Given the sheer quantity of analogue receivers in customers hands, and the average replacement cycle (surely 10 years plus) then this seems like a very pragmatic line to take.

It’s great news for those stations – they can continue on FM effectively as long as they like.  If DAB becomes mainstream in that time, no doubt they can just hand-back their FM licences – although they may think twice about freeing the band for unwelcome competition!

The full statement can be found on Ofcom’s website.


Ofcom FM/VHF Protection Ratios Illustrated


Ofcom are on the record stating that there is frequency congestion on the FM Broadcast band in many areas.  This can often cause frustration because to the layman it appears that there are plenty of unused frequencies on the dial.  The cause of this situation is the technical criteria that Ofcom use for their spectrum planning of this band.  There are many criteria, but in this post we focus on just one – the Protection Ratio, and in particular the co-channel (same channel) protection ratio.

It’s a bit of a dry subject, but has profound consequences.  Therefore we’ll use pictures and try and short-hand some of the technical language to make it more accessible.

Take by example our local Community Radio station – Bradley Stoke Radio (note we designed and commissioned their transmission system last year).  They broadcast with 25 watts on 103.4MHz from a low antenna attached to a community centre in North Bristol.   Their coverage area (the standard 54dBμV/m one that BBC and commercial stations use) is illustrated below – it’s that small green blob in the middle.


Click to Enlarge. Underlay map by google.com

Now the cynics among you will probably ask why such a big map – perhaps we are trying to exaggerate how small their coverage is – but there is method in our madness – please read on.

The above-mentioned Ofcom technical criteria state (on page 12) that the co-channel protection ratio for stereo services is 45dB.  To the layman that’s just a number, but to a radio engineer they think “heck that means the interfering signal has to be 31623 times smaller than the wanted signal to avoid interference half the time!”.  Gut feel indicates it can’t be right, but Ofcom cannot plan their spectrum strategy on gut-feel – the figures are based on internationally-recognised recommendations published by the ITU (page 5 of this document).   Adding this factor on top of little Bradley Stoke Radio’s signal results in an interference area indicated below.


Click to enlarge. Underlay map by google.com

That’s right – according to this protection ratio Bradley Stoke Radio’s lowly 25 watt transmitter effectively sterilises 103.4MHz across large swathes of south west England and south east Wales.  So in large areas from the southern edge of Birmingham, to Exeter, and Oxford to Cardiff it is not (apparently) possible to have another FM radio service on that channel.  This is borne-out by Ofcom’s actual frequency plan – only 11 transmitters on 103.4MHz across the entire UK.

UK Stations on 103.4MHz

UK Stations on 103.4MHz – Click to enlarge

This level of re-use is actually slightly above the national average of 9.3 (excluding the heavily under-utilised spectrum territory around 87.5-88.0MHz – presumably to ease the workload of RSL spectrum planning).

UK VHF/FM Frequency Re-use

UK FM channel re-use – Click to enlarge

To put that in context, each mobile phone network would probably have more than 50 20watt transmitters on the same frequency in Bristol alone and many hundreds across the same area of the UK.  However we are not comparing apples to apples there – the frequencies are different, and FM is an old analogue system that, in human terms, should be drawing its pension by now.   In contrast mobile phone networks are digital systems that have had over half a century extra human ingenuity in their development.  This is a major reason why Ofcom drives “re-farming” of spectrum from old to more spectrally efficient technologies (eg analogue to digital TV)

This is all caused by that 45dB protection ratio for FM.  It’s all too easy to stamp our feet and say “it must be wrong” – but as Scottie always said to Captain Kirk – “ye cannae change the laws of Physics“.  Nevertheless, there is a worthwhile goal here to achieve more listener choice and greater social gain – so could there be a third way?   Associated Broadcast Consultants think there could be – let’s outline a few possible approaches below:-

  1. Re-study the protection ratios.  We think this will not be a fruitful angle of approach.  Even with global warming, the laws of physics of radio propagation are unlikely to have changed over the last few decades.  True you could look at some of the assumptions (eg: that assumed receiving aerial height is 10m above ground level) – but in reality it could be difficult to get sufficient support to make this happen at ITU, and even if it were possible we’d probably all be pushing-up the daisies by the time the study finished!
  2. Band Re-plan.  An alternative approach is to re-plan the FM band to deliver a small amount of spectrum that is managed with lower protection ratios for use by stations at their own risk.  In practice this is not practical – too costly and disruptive to for wholesale frequency and power changes for a band/system with limited life.  Maybe if Radio 3 made an early exit from the FM band it could be an option to create a sub-band with tighter re-use of frequencies.
  3. Consider TSA instead of MCA – Many stations’ Target Service Area (TSA) is smaller than their Measured Coverage Area (MCA).  Therefore it seems rather a waste of spectrum to protect incumbent stations’ signals outside of their target area.  This approach could allow significantly denser packing of stations on the same channel.  Come to think of it, reduced protection may act as a gentle “nudge” to encourage incumbents to  transition to DAB should Ofcom want that.
  4. Review approaches of other regulators – There has been anecdotal evidence that other European regulators take a different approach to the ITU protection ratio recommendations (and other restrictions like the 10.7MHz image channel).  We are not aware of evidence of listeners in other countries complaining about FM interference any more than the UK.  Therefore we request Ofcom to consult their European colleagues and review what approaches to FM planning are taken in neighbouring countries.
  5. Pragmatic reduction in protection ratios – For example select a small number of stations that wish to have a power increase.  Carefully increase their power and see if there is any impact to the listen-ability of co-channel stations.  Most of those “interfered” stations will anyway be benefiting from increased protection since they came on-air because many will have alternative channels that could be used by listeners experiencing difficulties (eg DAB, satellite, DTV, mobile, internet…)

Associated Broadcast Consultants encourage Ofcom to consider options 3, 4 and 5 above. They are relatively small changes that should be within Ofcom’s power to change as part of its’ remit to efficiently manage the nation’s spectrum, and should not require primary legislation.

You are welcome to use the images and text in this post as long as you credit Associated Broadcast Consultants and give a link to this website.