Executive Summary
In December 2007, we published the Licence Exempt Framework Review (LEFR) Statement describing our policy on managing spectrum used by licence-exempt devices. One of the recommendations of the LEFR Statement was to open higher frequency bands for licence-exempt use.
The spectrum at high frequencies is characterised by severe atmospheric attenuation due to oxygen and water molecules, amongst other factors. To improve the link budget, directional antennas are used. Due to these factors and the large swathes of frequency available, the probability of harmful interference at high frequencies is low.
In this document, we propose to release the 275-3000 GHz band for licence-exempt use, subject to certain constraints such as power limits and excluding bands specified by Footnote 5.565 of the Radio Regulations for spectral line measurements. However, as Footnote 5.565 will be reviewed at the 2011 World Radiocommunication Conference (WRC-11), it will be premature to release this spectrum until the results of that conference are known. Hence, we propose to enact appropriate legislation after WRC-2011.
Given the low probability of harmful interference in the 275-3000 GHz band, our duty under Section 8(3) of the Wireless Telegraphy Act, is to make this band available for licence-exempt use. In addition, taking such an approach may encourage innovation and the emergence of new applications while reducing regulatory overheads.
The spectrum above 275 GHz is mainly used by the scientific community (radio-astronomy, space research and earth exploration satellite services) for spectral line measurements. However, other potential uses for the band include short range anti-collision radar devices, detection of skin cancer and other non destructive evaluation methods used in industrial processes.
We have used the power limits associated with non-generic short range devices (SRDs) in the 244-246 GHz band as a proxy for the power limit at 275 GHz. We believe that non-generic SRDs are a suitable proxy given that devices in the band of interest are likely to be short range and potentially be used for a range of applications. However, we propose to extrapolate this power limit appropriately for frequencies above 275 GHz to account for increased path loss with frequency.