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  2. National Distress System - Wikipedia

    en.wikipedia.org/wiki/National_Distress_System

    Predictions (except Alaska) were made by the DOD Joint Spectrum Center in Annapolis MD in March 1994. Note charts are predictions of radio coverage; actual radio coverage may vary. Some site locations have also changed since these predictions were made. The average chart file size is about 100 kb.

  3. Longley–Rice model - Wikipedia

    en.wikipedia.org/wiki/Longley–Rice_model

    A description of the method was published by the U.S. government under the title "Prediction of Tropospheric Radio Transmission Loss Over Irregular Terrain: A Computer Method - 1968", A. G. Longley and P. L. Rice, NTIA Tech. Rep. ERL 79-ITS 67, U.S. Government Printing Office, Washington, DC, July 1968.

  4. RF planning - Wikipedia

    en.wikipedia.org/wiki/RF_Planning

    In the context of mobile radio communication systems, RF planning is the process of assigning frequencies, transmitter locations and parameters to a wireless communications system to evaluate coverage and capacity. Coverage is the distance at which the RF signal has sufficient strength to sustain a call/data session.

  5. FM broadcast band - Wikipedia

    en.wikipedia.org/wiki/FM_broadcast_band

    The FM broadcast band is a range of radio frequencies used for FM broadcasting by radio ... The FM broadcast band in Japan uses 76 to 95 ... In March 2008, ...

  6. FM broadcasting in the United States - Wikipedia

    en.wikipedia.org/wiki/FM_broadcasting_in_the...

    Therefore, in effect, the FM broadcast band comprises only FM channels 201 (88.1 MHz) through 300 (107.9 MHz). Originally, FM stations in a market were generally spaced four channels (800 kHz) apart. This spacing was developed in response to problems perceived on the original FM band, mostly due to deficiencies in receiver technology of the time.

  7. List of channel numbers assigned to FM frequencies in North ...

    en.wikipedia.org/wiki/List_of_channel_numbers...

    In the Americas (defined as International Telecommunication Union (ITU) region 2), the FM broadcast band consists of 101 channels, each 200 kHz wide, in the frequency range from 87.8 to 108.0 MHz, with "center frequencies" running from 87.9 MHz to 107.9 MHz. For most purposes an FM station is associated with its center frequency.

  8. Coverage map - Wikipedia

    en.wikipedia.org/wiki/Coverage_map

    A coverage map may be produced to indicate the area in which a certain signal strength is delivered. [1] Even if it is 100% accurate (which it never is), a major factor on whether a signal is receivable depends very much on whether the receiving apparatus is sensitive enough to use a signal of that level.

  9. List of North American broadcast station classes - Wikipedia

    en.wikipedia.org/wiki/List_of_North_American...

    FM station class Reference (maximum) facilities for station class (ERP / HAAT) FM protected or primary service contour Distance to protected or primary service contour Distance to 70 dBu city-grade or principal community coverage contour Class A 6 kW 100 m (328 ft) 60 dBu (1.0mV/m) 28.3 km (17.6 mi) 16.2 km (10.1 mi) Class B1 25 kW 100 m (328 ft)