RES763 – 415 – ADD RESOLUTION 763 (WRC-15) Stations on board sub-orbital vehicles The World Radiocommunication Conference (Geneva, 2015), considering a) that the radio spectrum is a limited resource; b) that the boundary between the Earth’s atmosphere and space is usually assumed to be 100 kilometres above the Earth’s surface; c) that some vehicles, including aircraft, are being developed which can fly at altitudes of over 100 km into sub-orbital trajectories; d) that other vehicles may also operate at altitudes over 100 km and use non-orbital trajectories; e) that some of these vehicles reach space and after releasing the spacecraft, accelerate away and land on Earth as a sub-orbital space flight; f) that stations onboard sub-orbital vehicles may be using frequencies allocated to space and terrestrial services for the purpose of telemetry, tracking and command (TT&C) and voice communications, recognizing that the current regulatory provisions and procedures for terrestrial and space services may not be adequate for international recognition of the use of relevant frequency assignments by stations on board sub-orbital vehicles, recognizing further that the spectrum requirements for TT&C and voice communications on stations on board sub-orbital vehicles have not been studied, noting a) Question ITU-R 259/5, on Operational and radio regulatory aspects for planes operating in the upper level of the atmosphere; b) that provisions of No. 4.10 may apply for certain aspects of these operations, resolves to invite the ITU Radiocommunication Sector 1 to conduct studies to identify any required technical and operational measures, in relation to stations on board sub-orbital vehicles, that could assist in avoiding harmful interference between radiocommunication services; 2 to conduct studies to determine spectrum requirements and, based on the outcome of those studies, to consider a possible future agenda item for WRC-23; 3 to complete the studies within the next ITU Radiocommunication Sector (ITU-R) study cycle,