Analyst: Reuse 2G spectrum for 3G in rural areas

Reusing 2G spectrum for 3G services could successfully extend the reach of mobile broadband across rural and other thinly populated areas, an analyst group has said.

In a report entitled Prospects for UMTS900: status review and outlook and released on Thursday, Analysys Mason said allowing the practice, known as spectrum refarming, would make it economically feasible to roll out such services to currently unserved areas.

"At lower frequencies, radio signals propagate further, meaning that fewer sites are needed for network roll out," Catherine Viola, a senior analyst and the author of the report said in a statement. "At 900MHz, for example, networks can be built and operated with cost savings of around 50 to 70 percent compared with networks deployed in [2.1GHz] core-band 3G spectrum. These coverage and cost-saving benefits mean that operators can bring 3G services to less-densely populated areas that were previously uneconomical to cover."

The same refarming issue was the subject of a report issued on Tuesday by Kip Meek, chairman of the Broadband Stakeholder Group and spectrum adviser to the communications minister Lord Carter.

In Meek's report, entitled Report from the Independent Spectrum Broker: findings and policy proposals, the adviser addressed a current impasse in refarming negotiations between the UK's mobile operators.

This impasse is the result of the fact that Vodafone and O2 already have 2G spectrum at 900MHz, while Orange and T-Mobile's 2G spectrum is at 1800MHz — a frequency that has less reach than 900MHz. The fifth operator 3 has no 2G spectrum of its own — it only has 2.1GHz 3G spectrum, as do the other four operators.

More spectrum at 800MHz will become available over the coming years as a result of the digital switchover.

Viola pointed out that 3G networks using 900MHz 2G spectrum have already been successfully rolled out in Finland, Iceland, Australia, New Zealand, Thailand and Venezuela.

In Europe, the refarming of 2G spectrum for 3G services is not currently allowed, although the European Commission has made the relaxation of these rules a key part of its recent telecoms reform package.

The legal uncertainty surrounding refarming in the UK has led to delays in auctioning off the 2.6GHz '3G expansion' band — seen as essential to 4G services such as LTE and mobile WiMax — because, as they do not yet know whether they can reuse their 2G spectrum, the operators have not calculated how much they want to invest in 4G.

The situation is further complicated by the fact that 4G services are best rolled out over two types of spectrum — high bands such as 2.6GHz for high bandwidth, and low bands such as 900MHz or 800MHz for long-distance propagation.

Meek called for each of the four biggest operators to face a set cap on how much sub-1GHz spectrum and how much high-frequency spectrum they can possess. He recommended that Vodafone and O2 should only be able to get chunks of spectrum at 800MHz if they give up an equivalent amount of their 900MHz spectrum. He said, however, that this would allow them to bid for 2.6GHz spectrum with relatively few restrictions.

Orange and T-Mobile should be able to bid freely for 800MHz spectrum as they do not currently have any sub-1GHz stake, Meek said. However, he recommended that this should accompany limitations on the amount of 2.6GHz spectrum for which they are allowed to bid — unless they give up their 1800MHz or 2.1GHz spectrum.

3 and any potential new entrants into the UK mobile broadband market should be able to bid freely for both 800MHz and 2.6GHz spectrum, up to a set cap, Meek said.

Carter's acceptance or rejection of Meek's recommendations will become apparent with the publication next month of his final Digital Britain report.