§ 90.307   Protection criteria.

   The tables and figures listed in § 90.309 shall be used to determine the
   effective radiated power (ERP) and antenna height of the proposed land
   mobile base station and the ERP for the associated control station (control
   station antenna height shall not exceed 31 meters (100 feet) above average
   terrain (AAT)).

   (a) Base stations operating on the frequencies available for land mobile use
   in any urbanized area and having an antenna height (AAT) less than 152
   meters (500 feet) shall afford protection to co-channel and adjacent channel
   television stations in accordance with the values set out in tables A and E
   of § 90.309, except for channel 15 in New York, NY, and Cleveland, OH, and
   channel 16 in Detroit, MI, where protection will be in accordance with the
   values set forth in tables B and E in 47 CFR 90.309.

   (b) For base stations having antenna heights between 152 and 914 meters
   (500-3000 feet) above average terrain, the effective radiated power must be
   reduced below 1 kilowatt in accordance with the values shown in the power
   reduction graph in Figure A in § 90.309, except for channel 15 in New York,
   NY, and Cleveland, OH, and channel 16 in Detroit, MI, where the effective
   radiated power must be reduced in accordance with Figure B in § 90.309. For
   heights  of more than 152 meters (500 feet) above average terrain, the
   distance to the radio path horizon will be calculated assuming smooth earth.
   If the distance so determined equals or exceeds the distance to the Grade B
   contour of a co-channel TV station (Grade B contour defined in § 73.683(a) of
   this chapter), an authorization will not be granted unless it can be shown
   that  actual terrain considerations are such as to provide the desired
   protection at the Grade B contour, or that the effective radiated power will
   be further reduced so that, assuming free space attenuation, the desired
   protection at the Grade B contour will be achieved.

   (c) Mobile units and control stations operating on the frequencies available
   for land mobile use in any given urbanized area shall afford protection to
   co-channel and adjacent channel television stations in accordance with the
   values set forth in table C in § 90.309 and paragraph (d) of this section
   except for channel 15 in New York, NY, and Cleveland, OH, and channel 16 in
   Detroit, MI, where protection will be in accordance with the values set
   forth in table D in § 90.309 and paragraph (d) of this section.

   (d)  The minimum distance between a land mobile base station which has
   associated mobile units and a protected adjacent channel television station
   is 145 km (90 miles).

   (e) The television stations to be protected (co-channel, adjacent channel,
   IM, and IF) in any given urbanized area, in accordance with the provisions
   of paragraphs (a), (b), (c), and (d) of this section, are identified in the
   Commission's publication “TV stations to be considered in the preparation of
   Applications  for Land Mobile Facilities in the Band 470-512 MHz.” The
   publication  is available at the offices of the Federal Communications
   Commission in Washington, DC or upon the request of interested persons.

   [ 72 FR 35197 , June 27, 2007]

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