Expanding the radio spectrum available for licence-exempt applications such as Wi-Fi is just one of a number of options the European Commission is considering to drive wireless innovation and make the use of radio spectrum more efficient, a spokesman said this morning.

Growth in mobile and wireless data traffic has led to a shortage of available bandwidth, although new technologies are making it possible to share radio spectrum amongst several users - for example, by providing wireless broadband services in between licensed TV frequencies, in the so-called white spaces.

Other new wireless technologies are designed to share bands for which no licence is required. In the European Union, at least 40 million smart wireless devices are sold each year that use the harmonised 863-870MHz license-exempt band alone.

Although the are no concrete proposals to increase the number of license-exempt bands for the moment, Commission Digital Agenda spokesman Ryan Heath said that reducing licence restrictions is worth considering.

"For example, there is the possibility of additional harmonised licence-exempt spectrum for [Wi-Fi-type networks] in the 5GHz band. The success of the Wi-Fi model explains why such an approach merits examination."

Wi-Fi devices currently operate in the 2.4GHz band (for 802.11b/g devices) and in the less-congested 5GHz band (for 802.11a and some 802.11n devices).

"These and other frequencies used for short range devices might be expanded depending on the outcome of technical sharing studies and the potential for congestion," he said.

Extending licence-exempt bands is just one strand of the Commission's plan to make spectrum use more efficient. The other involves persuading licensed users to share their spectrum.

Yesterday the Commission called for national EU regulators to encourage spectrum sharing, without compromising the incumbent licence holders' rights to use the frequencies. According to the EU's Digital Agenda Commissioner, Neelie Kroes, national spectrum regulation often does not reflect the new technical possibilities, "leaving mobile and broadband users at risk of poor service as demand grows."

New regulatory approaches need to give different users, including current holders, guaranteed rights to use a given frequency band on a shared basis with guaranteed levels of protection against interference, the Commission said.

But this morning Heath clarified: "Forcing incumbents to share spectrum through regulation is not the aim of this Communication."

"Exclusive license holders have usually paid a significant premium to obtain their license, and may have had to invest significantly to provide ubiquitous coverage," he said. Therefore the Commission is looking for incentives to encourage incumbents to share their spectrum.