O2 UK and Vodafone Moot 4G Mobile Broadband via 900MHz.. Will it Work?

Several reports have suggested that O2 UK and Vodafone are considering the possibility of re-purposing their existing 900MHz radio spectrum for use by the next generation of 4G superfast mobile broadband (LTE) technology, which could be used as a means of combatting EE’s new 4G via 1800MHz service (details). Easier said than done.

As it stands EE (Everything Everywhere), which is under pressure from UK government, has agreed not to switch-on its new 4G service for at least three more weeks while secret talks between the heads of all the major mobile operators are taking place. In short EE’s rivals are unhappy that the operator would be able to launch 4G ahead of everybody else (one full year ahead).

One possible solution being mooted would be for O2 and Vodafone to simply re-use their existing 2G/3G based 900MHz spectrum to launch a 4G service sooner rather than later. Both Europe and Ofcom have, just as with the 1800MHz band before it, suggested that such a change would be fine. But could it actually work?

Limited Spectrum

One of the reasons that EE has been able to launch 4G so soon and over 1800MHz is because it has plenty of spectrum to spare (2 x 30MHz for each of Orange UK and T-Mobile). This will be reduced from September 2013 when they’re forced to sell off 2 x 15MHz to rival Three UK but that still leaves enough for a 4G / LTE service via their shared network infrastructure.

By comparison O2 UK and Vodafone each have one block of paired 2 x 17.5MHz in the 900MHz band (please correct us if we’re wrong), while to get the most from an LTE service you really need 20MHz (it can work with 10MHz but that’s not particularly attractive). To clarify, an entry of 2 x 17.5MHz means a total of two blocks of 17.5MHz, one designated for upload and the other for download. The blocks may not be contiguous and could be fragmented across the band.

Other Problems

On top of that O2 UK has already put significant investment into launching 3G services over the 900MHz band (here), which occurred in March last year after Ofcom allowed the operator to expand its uses beyond the slower 2G-only services. Changing this again so soon might not be the best move and could agitate some customers.

Suffice to say that both O2 and Vodafone would ideally need more 900MHz spectrum to deliver 4G properly, without compromising other requirements. Similarly Three UK might be unhappy about being left as the odd one out (forced to wait for 800MHz and 1800MHz until the end of 2013).

A better solution might simply be for O2 and Vodafone to capitalise on the affordable coverage advantages of 900MHz and deploy faster HSPA+ mobile broadband technology into more parts of the country. At this early stage of 4G’s development there’s not likely to be much difference between that and a strong HSPA+ setup but they’re naturally rather do all of this via 4G.