Using technology will save broadcasters money
Posted: May 1, 2022
The FCC appears to be moving quickly toward allowing FM broadcasters in the United States to use computer modeling software for their directional antennas.
A new draft order was introduced just six months after the commission issued a notice of proposed rulemaking based on a petition from antenna makers Dielectric, Jampro Antennas, Radio Frequency Systems and Shively Labs. Manufacturers want the FCC to allow FM broadcasters the ability to submit computer models to reduce tower project costs without compromising technical standards.
The draft executive order will be considered for adoption at the FCC’s monthly meeting on May 19.
When applying for a license, FM radio stations using directional antennas are currently required to provide physical measurements to verify their directional pattern. To do this, stations or their representatives must build a full-size model of the antenna or a scale model. This type of work is usually done by the antenna manufacturer.
The proposed order would give plaintiffs the option of submitting computer-generated evidence of manufacturer’s FM directional antenna patterns, instead of charts and tabulations of measured patterns.
Detailed information on who performed the computer modeling should be provided, according to the FCC.
Additionally, the rules would require “a description of the computer modeling software used and the procedures applied when using the software, including a description of any radiating structures included in the model,” according to the draft proposal.
Additionally, the commission is set to require that the first time the directional model of a particular antenna model is verified using computer results, the FM station will be required to submit the computer modeling results and measurements of a full-size or scale model. antenna model; again, this would likely be done in concert with the manufacturer.
The FCC says the requirement “is to demonstrate a reasonable correlation between the measurements obtained and the results of the computer model.”
It continues: “Once a particular antenna model or series of elements has been verified by a license applicant, subsequent license applicants using the same antenna model number or elements and the same modeling software can reference the original submission by providing the application file number. “, concluded the FCC.
The commission appears to have decided not to broaden the range of entities authorized to perform computer modeling beyond manufacturers.
Referring to comments he received in his NPRM, he wrote: “While commentators largely agree that license applicants should be able to rely on manufacturer’s computer modeling to verify FM directional patterns for antennas of this manufacturer, there was less agreement as to whether others should be allowed. to perform computer modeling to verify FM directional antenna patterns.
Chair Jessica Rosenworcel, in her overview of this month’s meeting, said the proposed order would “lower regulatory costs and bring our FM regulations in line with other broadcast services.”
The commission calls the revision a “modest rule change” that allows for similar treatment of performance verification of FM and LPFM directional antennas to that used for AM and DTV licensing.
According to the FCC, the most common reason a full-power commercial FM uses a directional antenna is to allow it to “short-space” to another FM station while maintaining that station’s contour protection. There are about 900 licensed directional FM stations in the United States, according to the commission.
The National Association of Broadcasters mostly agreed with the FCC’s original proposal to allow directional FMs to rely on computer modeling and move away from required real-world testing, calling computer modeling the FM directional networks of “already mature and capable of producing physics-like accuracy”. measurements.” However, antenna maker Electronics Research Inc. expressed concerns about the proposed change.
[Related: “NAB Sees Benefits of FM Directional Antenna Modeling”]