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LPFM Report and Order: Difference between revisions
→Spectrum for LPFM
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=== Spectrum for LPFM === | === Spectrum for LPFM === | ||
The FCC decided to authorize low power radio only on the FM band. For AM, the FCC cited the congestion and interference on the band. In addition low power AM stations were capable of significantly higher levels of interference as a result of propagation characteristics. | |||
For FM, the FCC has concluded that no specific frequency can be assigned for LPFM as all of the channels are used nationwide. Channels 201~220 (88.1~91.9) are already available for full-power NCE stations and they would also be available for LPFM stations. Stations would also be allowed in the commercial band Channels 221~300 (92.1~107.9). | |||
LPFM stations would be able to obtain broadcast auxiliary services such as studio to transmitter links, but such operation would be secondary to use by full-service broadcast stations. | |||
=== Spectrum rights and responsibilities === | === Spectrum rights and responsibilities === | ||
On the issue of secondary vs. primary service, comments were divided. Several commenters wanted primary service to help ensure LPFM's survival. Broadcasters and consulting engineers felt that LPFM should be secondary on the same level as FM translators. | |||
The FCC made the LPFM service secondary and also provide protection to FM translator and booster stations. LPFM stations will also be required to protect vacant FM allotments. With that in mind, the FCC wanted to minimize the situations in which an LPFM station would be required to change channels or cease operating. LPFM stations will be required to protect full-service and translator stations using distance separation. In addition, LPFM stations in the reserved band (88.1~91.9) would also have to protect full-service and low power Channel 6 TV stations. | |||
In respect to full-service stations, the FCC included a 20 kilometer "buffer" to the distance separation requirements for co-channel and first-adjacent channels. The buffer will protect FM radio facilities that were modified or upgraded in a manner that would create a short-spacing with an LPFM station. LPFM stations would not be required to eliminate interference caused to FM stations by their lawful operation. FM stations will also be required to address complaints of blanketing interference and will be subject to international agreements and must eliminate interference to primary Canadian or Mexican broadcast stations. | |||
In the rules, the FCC will include two distances in respect to co-channel and first-adjacent stations. The first distance is the required minimum separation distance that includes the interfering contour of the LPFM station, the 20 km buffer zone (towards full-service stations only) and the protected service contour of the incumbent station. The second distance will be the minimum distance where the LPFM station would likely not receive interference from the incumbent station. This consists of the interfering contour of the incumbent station plus the service contour of the LPFM station (no buffer zone). | |||
If a full-service station modifies their facility, the LPFM station may have to cease operations if the LPFM station causes interference in the full-service station's 70 dBu contour. | |||
=== Minimum distance separation requirements === | === Minimum distance separation requirements === | ||