RES656 – 375 – ADD RESOLUTION 656 (WRC-15) Possible allocation to the Earth exploration-satellite service (active) for spaceborne radar sounders in the range of frequencies around 45 MHz The World Radiocommunication Conference (Geneva, 2015), considering a) that the 40-50 MHz range is allocated to the fixed, mobile and broadcasting services on a primary basis;b) that the uses of the 40.98 to 41.015 MHz frequency range by the space research service are on a secondary basis; c) that country footnotes in the Table of Frequency Allocations for the 40-50 MHz frequency range provide primary allocations for the aeronautical radionavigation and radiolocation services in certain parts of the world; d) that spaceborne radars are intended to be operated only in either uninhabited or sparsely populated areas of the globe, with particular focus on deserts and polar ice fields, and only at night-time from 3 a.m. to 6 a.m. locally; e) that Recommendation ITU-R RS.2042-0 provides typical technical and operating characteristics for spaceborne radar sounder systems using the 40-50 MHz frequency range that should be used for interference and compatibility studies,recognizing a) that spaceborne active radio-frequency sensors can provide unique information on physical properties of the Earth and other planets; b) that spaceborne active remote sensing requires specific frequency ranges depending on the physical phenomena to be observed; c) that there is an interest in using active spaceborne sensors in the vicinity of the 40-50 MHz frequency range for measurements of the Earth’s subsurface to provide radar maps of subsurface scattering layers with the intent to locate water/ice/deposits; d) that worldwide, periodic measurements of subsurface water deposits require the use of spaceborne active sensors; e) that the 40-50 MHz frequency range is preferable to satisfy all requirements for spaceborne radar sounders,