§ 22.911   Cellular geographic service area.

   The Cellular Geographic Service Area (CGSA) of a cellular system is the
   geographic area considered by the FCC to be served by the cellular system.
   The  CGSA  is  the  area within which cellular systems are entitled to
   protection and within which adverse effects for the purpose of determining
   whether a petitioner has standing are recognized.

   (a) CGSA determination. The CGSA is the composite of the service areas of
   all of the cells in the system, excluding any Unserved Area (even if it is
   served on a secondary basis) or area within the CGSA of another Cellular
   system. The service area of a cell is the area within its service area
   boundary (SAB). The distance to the SAB is calculated as a function of
   effective radiated power (ERP) and antenna center of radiation height above
   average terrain (HAAT), height above sea level (HASL), or height above mean
   sea level (HAMSL).

   (1) Except as provided in paragraphs (a)(2) and (b) of this section, the
   distance from a cell transmitting antenna to its SAB along each cardinal
   radial is calculated as follows:

   d = 2.531 × h0.34 × p0.17

   where:

   d is the radial distance in kilometers

   h is the radial antenna HAAT in meters

   p is the radial ERP in Watts

   (2) The distance from a cell transmitting antenna located in the Gulf of
   Mexico  Service  Area  (GMSA) to its SAB along each cardinal radial is
   calculated as follows:

   d = 6.895 × h0.30 × p0.15

   Where:

   d is the radial distance in kilometers

   h is the radial antenna HAAT in meters

   p is the radial ERP in Watts

   (3) The value used for h in the formula in paragraph (a)(2) of this section
   must not be less than 8 meters (26 feet) HASL (or HAMSL, as appropriate for
   the support structure). The value used for h in the formula in paragraph
   (a)(1) of this section must not be less than 30 meters (98 feet) HAAT,
   except that for unserved area applications proposing a cell with an ERP not
   exceeding 10 Watts, the value for h used in the formula in paragraph (a)(1)
   of this section to determine the service area boundary for that cell may be
   less than 30 meters (98 feet) HAAT, but not less than 3 meters (10 feet)
   HAAT.

   (4) The value used for p in the formulas in paragraphs (a)(1) and (a)(2) of
   this section must not be less than 0.1 Watt or 27 dB less than (1/500 of)
   the maximum ERP in any direction, whichever is more.

   (5) Whenever use of the formula in paragraph (a)(1) of this section pursuant
   to the exception contained in paragraph (a)(3) of this section results in a
   calculated distance that is less than 5.4 kilometers (3.4 miles), the radial
   distance to the service area boundary is deemed to be 5.4 kilometers (3.4
   miles).

   (6) The distance from a cell transmitting antenna to the SAB along any
   radial  other  than the eight cardinal radials is calculated by linear
   interpolation of distance as a function of angle.

   (b) Alternative CGSA determination. If a carrier believes that the method
   described in paragraph (a) of this section produces a CGSA that departs
   significantly (±20% in the service area of any cell) from the geographic
   area where reliable cellular service is actually provided, the carrier may
   submit, as an exhibit to an application for modification of the CGSA using
   FCC Form 601, a depiction of what the carrier believes the CGSA should be.
   Such submissions must be accompanied by one or more supporting propagation
   studies using methods appropriate for the 800-900 MHz frequency range,
   including all supporting data and calculations, and/or by extensive field
   strength measurement data. For the purpose of such submissions, cellular
   service is considered to be provided in all areas, including “dead spots”,
   between the transmitter location and the locus of points where the predicted
   or measured median field strength finally drops to 32 dBµV/m (i.e. does not
   exceed 32 dBµV/m further out). If, after consideration of such submissions,
   the FCC finds that adjustment to a CGSA is warranted, the FCC may grant the
   application.

   (1) The alternative CGSA determination must define the CGSA in terms of
   distances from the cell sites to the 32 dBuV/m contour along the eight
   cardinal radials, with points in other azimuthal directions determined by
   the method given in paragraph (a)(6) of this section. The distances used for
   the cardinal radials must be representative of the coverage within the 45�°
   sectors, as depicted by the alternative CGSA determination.

   (2) If an uncalibrated predictive model is used to depict the CGSA, the
   alternative CGSA determination must identify factors (e.g. terrain roughness
   or features) that could plausibly account for the difference between actual
   coverage  and  that defined by the formula in paragraph (a)(1) of this
   section. If actual measurements or a measurement-calibrated predictive model
   are used to depict the CGSA, and this fact is disclosed in the alternative
   CGSA determination, it is not necessary to offer an explanation of the
   difference  between actual coverage and that defined by the formula in
   paragraph (a)(1) of this section. If the formula in paragraph (a)(1) of this
   section  is clearly inapplicable for the cell(s) in question (e.g. for
   microcells), this should be disclosed in the alternative CGSA determination.

   (3)  The  provision  for  alternative  CGSA determinations was made in
   recognition  that the formula in paragraph (a)(1) of this section is a
   general model that provides a reasonable approximation of coverage in most
   land areas, but may under-predict or over-predict coverage in specific areas
   with unusual terrain roughness or features, and may be inapplicable for
   certain  purposes,  e.g.,  cells with a coverage radius of less than 8
   kilometers (5 miles). In such cases, alternative methods that utilize more
   specific models are appropriate. Accordingly, the FCC does not consider use
   of the formula in paragraph (a)(1) of this section with parameters outside
   of the limits in paragraphs (a)(3), (a)(4) and (a)(5) of this section or
   with  data  for  radials other than the cardinal radials to be a valid
   alternative method for determining the CGSA of a cellular system.

   (c) [Reserved]

   (d) Protection afforded. Cellular systems are entitled to protection only
   within  the  CGSA (as determined in accordance with this section) from
   co-channel and first-adjacent channel interference and from capture of
   subscriber traffic by adjacent systems on the same channel block. Licensees
   must  cooperate  in  resolving  co-channel  and first-adjacent channel
   interference  by  changing channels used at specific cells or by other
   technical means.

   (e) Unserved Area. Unserved Area is area outside of all existing CGSAs on
   either of the channel blocks, to which the Communications Act of 1934, as
   amended, is applicable.

   [ 59 FR 59507 , Nov. 17, 1994, as amended at  59 FR 59954 , Nov. 21, 1994;  63 FR 68951 , Dec. 14, 1998;  67 FR 9609 , Mar. 4, 2002;  67 FR 77191 , Dec. 17, 2002;
    68 FR 42295 , July 17, 2003;  79 FR 72151 , Dec. 5, 2014]

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