ANATEL issued Official Letter No. 81/2025 with regards to 5150-5350 MHz frequency band in vehicular applications, in response to a request from the OCD committee.
As a result of this letter, the following points have been clarified:
Under Act 14448, indoor environments are defined as spaces that decrease radio emissions through signal attenuation, such as walls or vehicle enclosures. Based on this interpretation, ANATEL has confirmed that only fully enclosed vehicles—such as cars and trucks—are permitted to operate within this frequency band.
Consequently, vehicles like motorcycles, tuk-tuks, and convertible cars do not meet the criteria for indoor environments and are prohibited from using the 5150–5350 MHz frequency range.