Licence-exempt or unlicensed spectrum denotes frequencies used without the need for a licence by short-range devices (SRD) such as remote controls, telemetry equipment, alarm or motion detector devices, but also devices used to transmit sound or voice and, of course, Wi-Fi. Nowadays it also relates to a wide range of applications associated with the Internet of Things (IoT), in sectors such as industry, motorcars, smart homes, logistics or medicine. Although the term SRD is still employed, suggesting that these usages remain “short-range”, these devices can have much wider uses. The Internet of Things has seen the emergence of what are known as Low Power Wide Area Networks (LPWAN) and their associated usages: smart cities, connected homes or health, for example. These networks rely on access to licence-exempt spectrum.
On the regulatory front, SRDs use spectrum under a general authorisation regime formalised by ARCEP decisions: they may transmit freely as long as they comply with predetermined technical parameters such as transmission power, for example, or timing of use. SRDs enjoy no protection from other authorised usages. These parameters, inferred from deployment scenarios, determine the radio environment for these devices: they must share spectrum with other devices subject to the same constraints and, in certain frequency bands, with primary usages (government requirements or based on an individual authorisation) that then take priority.
Such devices are extremely varied in nature and are developing swiftly as a result of the rapidly expanding IoT. Devices coming to market also enjoy free movement throughout the European Union. If the sector is to develop, therefore, a harmonised regulatory framework is essential.
The most commonly known licence-exempt bands are found in the following ranges: 6.7 MHz, 13.56 MHz, 27 MHz, 40.7 MHz, 169.4 MHz, 433 MHz, 868 MHz, 2.4 GHz, 5.8 GHz, 24-24.25 GHz, 60 GHz, 122 GHz and 244 GHz. They are widely recognised and their regulatory framework is geared to SRD applications.
It is possible for SRDs to use other frequency bands, but this is limited to specific applications and under stricter conditions for sharing with incumbent services. The 5GHz range, for example, is available to Wi-Fi networks but must be shared with earth exploration-satellite systems (EESS) or with radar systems, which means that advanced interference reduction techniques are required. Specific regulations also exist for medical implants authorised in the 401-406 MHz band, or for hearing aids and for intelligent transport systems (5.9 GHz and 63 GHz).
Ultra Wide Band (UWB) applications follow the same logic. These devices, which are used for communication, location or radar imaging, require very wide bandwidths that are necessarily already in use by radiocommunication systems with very varied characteristics.
ANFR will support the development of shared use of licence-exempt bands, which offer considerable opportunities for innovation for both IoT and for Wi-Fi. The Agency will pay particular attention to defining the technical conditions governing the coexistence between SRD applications (IoT in particular) and with other users of the bands concerned.
ANFR will examine the possibilities for relaxing the constraints applicable to Wi-Fi in the 5 GHz and 57-66 GHz bands.
In order to meet the growing needs of IoT, ANFR will support at European level the adaptation of the EU framework to needs expressed at national level, particularly during the summer 2016 consultation on new opportunities for use of the 862-870 MHz, 870-876 MHz and 915-921 MHz bands.