Spectrum neutrality is within the grasp of the radiocommunications industry – if the business is careful enough.
Regulators are eager to offer spectrum resources on a service- and technology-neutral basis, but what the neutrality concept actually means – and whether it has to come with a caveat – has been the subject of much debate.
The situation may, though, be a lot simpler than it appears. ATDI managing director Cyprien de Cosson says: “Yes, you can offer spectrum without constraint on service or technology – provided that you have completed the significant analysis that is needed to underpin the policy of doing so.”
Neutrality means that an operator can use any technology, topology or service (and with that any modulation scheme, radiated power and channel bandwidth) in a future network. Regulators value the concept because it gives flexibility and, thus, maximises spectrum value. While the idea of neutrality has long been discussed, its practical application is now in the spotlight over the future release of the 2.6GHz band. In addition, it is also being considered in the context of the digital dividend bands in the 700MHz region and recently proposed liberalisation bands at 900MHz and 1800MHz that are currently designated for 2G services only.
Neutrality applies to regional licences where sharing might be constrained by limited field strengths at allotment boundaries and to licences for adjacent spectrum where block edge masks control emissions into adjacent allotments.
To be able to claim neutrality, a regulator must first project the market demand and the industry supply, setting out the technologies that currently use the bands and those that will use the bands in the future. Current allocation differs country by country and future allocation may also vary by territory as regulators seek to match spectrum use to social and economic policy.
“Modelling can then be used to explore interference and to select the envelope of constraints that, when met, will permit a conditional neutrality,” Cyprien states. “There’s still a risk that some combination of service, topology and technology will be selected that causes interference between new and established services but if the right analysis has been done and the right constraints selected, the risk is likely to be low.”
He argues, then, that neutrality can be announced as a policy but if due diligence is done, adding: “Neutrality must not make way for laissez faire spectrum management. Regulators must not follow their neighbour but must undertake the necessary analysis to control the interference experienced by future licence holders.”