SWRA797 September 2024 CC1312PSIP
Use a certified antenna that has already been listed in the original FCC filing. By using a certified antenna, then the end-user using the FCC IC label does not need to prove the antenna gain since this is a known antenna and known antenna gain.
If a non-certified antenna is used, then the end-user must prove the antenna gain does not exceed 2.69dBi. Section 3.2.2 covers the items required when filing a new antenna and how to prove the antenna gain so this is accepted by the FCC. A class II permissive change is only required when the antenna gain exceeds 2.69dBi.