Low-power broadcasting
Low-power broadcasting is broadcasting by a broadcast station at a low transmitter power output to a smaller service area than "full power" stations within the same region. It is often distinguished from "micropower broadcasting" (more commonly "microbroadcasting") and broadcast translators. LPAM, LPFM and LPTV are in various levels of use across the world, varying widely based on the laws and their enforcement.
"Low-power radio" redirects here. For other low-power radio-wave communications, see Near-field communication and Low-power wide-area network.Canada[edit]
Radio communications in Canada are regulated by the Radio Communications and Broadcasting Regulatory Branch, a branch of Industry Canada, in conjunction with the Canadian Radio-television and Telecommunications Commission (CRTC). Interested parties must apply for both a certificate from Industry Canada and a license from CRTC in order to operate a radio station. Industry Canada manages the technicalities of spectrum space and technological requirements whereas content regulation is conducted more so by CRTC.
LPAM stations are authorized to operate with less than 100 watts of power.[1]
LPFM is broken up into two classes in Canada, Low (50 watts) and Very Low (10 watts). The transmitters therefore range from 1 to 50 watts, as opposed to 1 to 100 watts in the U.S. As of 2000, 500 licenses (very low and low-power FM) have been issued. These transmitters are generally only allowed in remote areas.
Stations in the low-power class are subject to the same CRTC licensing requirements, and will generally follow the same call sign format, as full-power stations. Stations in the very low-power class formerly had to have CRTC licenses as well, although a series of CRTC regulation changes in the early 2000s exempted most such stations from licensing; a station in this class will usually not have a conventional call sign, but will instead be identified in a naming format consisting of a four-digit number preceded by the letters CH for a television station or VF for a radio station.
The regulation of spectrum space is strict in Canada, as well having restrictions on second and third adjacent channels, along with other protections for AM and FM commercial radio. In addition, because there have been a few cases that found that FM frequencies have caused interference to the aeronautical navigation and communications (NAV/COM) spectrum (though evidence is not very concrete presently), pirate radio regulation has remained very strict as well. However, the two regulating bodies do have certain exemptions. For example, low-power announcement transmitters that meet the requirement of Broadcasting Equipment Technical Standards 1, Limited Duration Special Events Distribution Undertakings, Temporary Resource Development Distribution Undertakings, and Public Emergency Radio Undertakings are a few instances, which according to certain criteria, may be exempt from certificate/license requirements.[2]
A television station is considered very low power if its power does not exceed 2 watts for a VHF station, or 10 watts for a UHF station. [3] Low-power analog & digital television stations are authorized to operate with up to 50 watts in VHF, or 500 watts for a UHF station.[4][5]
New Zealand[edit]
In New Zealand residents are allowed a broadcast license (free-of-charge) at a maximum of 1 watt EIRP in the FM guardbands from 87.6 to 88.3 and from 106.7 to 107.7 MHz under a General User Radio License (GURL), which is issued by Radio Spectrum Management, managed by the Ministry of Business, Innovation and Employment. Prior to June 2010, the lower band was located between 88.1 and 88.8 and a maximum of 500 mW EIRP allowed. Broadcasters on these frequencies are required to cease operations if they interfere with other, licensed broadcasters and have no protection from interference from other licensed or unlicensed broadcasters. Contact details must also be broadcast every hour.[6]
Further restrictions are in place for the protection of aeronautical services. Use of the following frequencies is not permitted within certain boundaries approaching Auckland and Wellington airports:[7] 107.5 to 107.7, and 107.0 to 107.3 MHz, respectively.
There exists a 25 km broadcast translator rule: one licensee may operate two transmitters anywhere (close together), but a third transmitter must be at least 25 km away from at least one of the first two transmitters.[6]
There are efforts on self-regulation of the broadcasters themselves. The NZRSM Radio Inspectors do, however, regularly monitor and make random unannounced visits to broadcasters, and will impose fines for violations of the regulations. New broadcasters are also subject to an initial compulsory inspection.
United States[edit]
FM radio[edit]
Low Power FM (LPFM) is a non-commercial educational broadcast radio service created by the Federal Communications Commission in the United States in 2000. LPFM licenses, which are limited to a maximum effective radiated power (ERP) of 100 watts, may be issued to non-commercial educational entities, as well as public safety and transportation organizations. Individuals and holders of other types of broadcast licenses are not eligible. In addition, LPFM stations are not protected from interference from other classes of FM stations.[8]