Recent press reports (e.g. here and here) revealed that O2 UK has expanded their 3G service to the 900 MHz band in London and other big cities in the UK. Quite a surprising move for me since the common perception is that there is not enough bandwidth in the 900 MHz range to allow operators to remove a 5 MHz chunk from GSM services in busy cities and use it for UMTS in this band. So how is this possible in the UK from a technical point of view?
After some digging I have found the two references (here and in particular here) that suggest that in the UK, the 2x35 MHz bandwidth in the 900 MHz band is only shared between two network operators. That makes things very easy from a technical point of view as each operator has much more spectrum compared to countries in which up to four network operators share the resource.
In a first instance, this is very good for customers since 3G indoor coverage should be considerably enhanced by this. Personally, I can't wait to come to London again to get some first hand experience.
From a competitive point of view the move by Ofcom to allow the incumbent two operators to keep all the spectrum and to use it for more than just GSM (refarming) must have been a very difficult one as it puts the other operators at a disadvantage in the short and medium term. Until they can get similar spectrum, e.g. in the 800 MHz band, until manage to deploy a network and until they can get devices, a significant amount of time will pass.
And here's why: The bandwidth auctions for the 800 MHz band in the UK is set for 2Q2012 and there are still some question marks attached. And once that spectrum is allocated it is most likely going to be used for LTE. That's good for high speed Internet access with 3G dongles and embedded 3G/LTE modules but that still leaves the LTE voice problem to be solved. Here's a post of mine from back in 2008 describing the issue. It's 2011 now and I don't see that the industry has moved an inch closer to a solution (dual radio mobiles don't count).
It's not the additional 5 MHz that is the business advantage, it's the indoor coverage. And smartphone owner don't care only for 2G indoor coverage they want fast Internet access as well. According to this report (again, but see (*) below) the 900 MHz operators have to pay a yearly fee to compensate for the fact that 2100 MHz 3G operators would have to build three times more base stations in order to reach a similar coverage. But that's easier said than done, just imagine how an operator could triple the number of base stations in London. I wonder if that yearly fee (how much is it by the way?), which in theory should make tariffs more expensive with the 900 MHz operators, will be enough to ensure ongoing competition between four network operators. I am a bit skeptical.
Would it have been better to give some of the 900 MHz spectrum to other network operators? Difficult question. Perhaps it would have been a bit more fair in that band but it would also have meant that, according to current wisdom, there would have been no 900 MHz 3G in the UK, just like in other countries. That leaves the 800 MHz digital dividend band for fast Internet services with good indoor coverage in cities and economical rural coverage like in other countries. Unfortunately, the bandwidth of 30 MHz there is not enough for four operators, three is the best you can reasonable do here.
(*) P.S.: The article states that EE uses 1800 MHz for 3G services. That is unlikely as there are no 1800 MHz 3G devices on the market today.