FCC Adopts Antenna Computer Modeling Rules for FM/LPFM Directional Antennas

The FCC adopted a Report and Order that gives FM and Low Power FM (LPFM) applicants using directional antennas the option of verifying the directional pattern through the use of computer modeling.

Some FM stations use directional antennas in order to prevent interference to other stations or to keep the signal from radiating outside the station’s authorized service area. When seeking a license, FM radio stations using directional antennas are required to provide measurements of the radiated signal to verify their directional pattern. To do this, stations must either build a full-size mockup of the antenna or build a scale model. These measurements can involve considerable expense to the applicant.

Today’s action gives FM and LPFM broadcasters the option to verify directional antenna patterns by using computer modeling prepared by the antenna manufacturer rather than real world measurements, after the model is initially verified for accuracy. The action will provide regulatory relief for both antenna manufacturers and FM broadcasters while maintaining the integrity of the Commission’s licensing requirements.

Update: New rules effective November 10, 2022 upon publication in the Federal Register. See Public Notice here.


Report & Order [153 KB PDF]
News Release [149 KB PDF]