Oh no, not another UMTS frequency. After UMTS 2100 MHz (the original UMTS frequency as used in Europe) and UMTS 1900 MHz and 850 MHz (as used in the US by Cingular), O2 has started trials to use UMTS at its 900 MHz frequency currently used by GSM operators to carry its 2G and 2.5G services. The trials, which are taking place on the operator's Isle of Man network - often used to test out new technologies (and O2's first UMTS network) - are designed to see how UMTS protocols and services will work at lower frequencies than the 2100 MHz currently mandated for 3G usage.
O2 is keen on UMTS at 900 MHz because it means it can cover greater areas in a cell site and also get better in-building coverage than higher frequency radio waves offer.
Dave Williams, O2's CTO, said that the operator wanted to see if it could get an increase in coverage and in-building penetration whilst avoiding interference with other services at the frequency:
"We want to try and prove that UMTS will share the same link budget at 900MHz, and to try and prove that in a real trial," Williams said.
"What good would look like from these trials is if we get the same figures and link budget as 900 Mhz. It would essentially then be an electronics upgrade to the existing base stations," Williams added.
Getting UMTS to work at lower frequencies with the same performance as GSM would help operators because it would mean they could cover areas without needing to site new base stations or equipment.
However, the road ahead is not completely smooth for O2. There is no regulatory approval in its markets for 3G at 900 or 1800 MHZ for that matter. And although Williams says he thinks there will be handsets for UMTS at 900 MHz by early next year, that seems aggressive.
But Williams pointed out that Cingular already has GSM and UMTS services at 850Mhz in the USA, and that the band is already standardized within 3GPP.
"This is a long term deployment effort. Years from now all 2G spectrum will be used for 3G beyond work on regulation and spectrum. 2G spectrum will clearly be used for 3G and different countries will take different approaches in allowing that the happen. When they do we want to make sure we've tested the technology," Williams said.
UMTS 900 terminals early next year sounds pretty optimistic, I don't think so (and if so, it means we will see quadband UMTS terminals which also have to support quadband GSM) but anyway, the trials will take much longer anyway - I think.
Cheers ~ Arne