ANATEL and ANAC monitor coexistence between future 5G bands and aeronautical radars

Brazil’s National Telecommunications Agency (ANATEL, in Portuguese) and Brazil’s Civil Aviation Agency (ANAC, also in Portuguese) have been monitoring the 4200-4400 MHz band to ensure the protection of the Aeronautical Radionavigation service. The use of the band around 4GHz is monitored by both bodies, so that, if necessary, interference mitigation actions are evaluated. These studies began this year, considering the essentiality of radio altimeters – devices that calculate the height of an aircraft above the ground, a critical system in aircraft operation – for flight safety and the decision of the US government to use the range 3700-3980 MHz for commercial 5G networks. The position of the United States has generated concern in the civil aviation sector, given the characteristics of fifth-generation networks, such as greater transmission power, in addition to the use of antennas with beam shaping. This move has generated discussions at the International Civil Aviation Organization (ICAO), which currently recommends a 200 MHz spectral separation in relation to international mobile telecommunications (IMT) systems to protect radio altimeters operating in the 4200-4400 MHz band. American decision on the use of the 3.9 GHz band, it should be noted, has no parallel with 5G in Brazil in the 3.5 GHz band (3300-3700 MHz). – https://www.gov.br/anac/pt-br/noticias/2021/anatel-e-anac-acompanham-convivencia-entre-faixas-futuras-do-5g-e-radares-aeronauticos