World radiocommunication conferences (WRC) are held every three to four years. It is the job of WRC to review, and, if necessary, revise the Radio Regulations, the international treaty governing the use of the radio-frequency spectrum and the geostationary-satellite and non-geostationary-satellite orbits.
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Website Address: https://www.itu.int/en/ITU-R/conferences/wrc/2019/Pages/default.aspx