Sec.  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 area outside the cellular
   market boundary, except as provided in paragraph (c) of this section, and
   excluding any 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×h^0.34 xp^0.17

   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 × h^0.30 × p^0.15

   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 dB �V/m (i.e. does not
   exceed 32 dB �V/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) CGSA extension areas. SAB extensions (areas outside of the cellular
   market boundary, but within the service area as calculated using the methods
   of paragraph (a) of this section) are part of the CGSA only under the
   following circumstances:

   (1) During the five year build-out period of the system in the cellular
   market containing the extension, the licensees of systems on the same
   channel block in adjacent cellular markets may agree that the portion of the
   service area of one system that extends into unserved areas in the other
   system's cellular market is part of the CGSA of the former system.

   (2) At the end of the five year build-out period of the system in the
   cellular market containing the extension, the portion of the service area
   that extends into unserved areas in another cellular market becomes part of
   the CGSA, provided that the licensee of the system so extended files a
   system information update in accordance with  Sec. 22.947(c).

   (3) For original systems in MSAs, extensions of the CGSA authorized by the
   FCC are part of the CGSA to the extent authorized.

   (d) Protection afforded. Within the CGSA determined in accordance with this
   section, cellular systems are entitled to protection from co-channel and
   first-adjacent channel interference and from capture of subscriber traffic
   by adjacent systems on the same channel block.

   (1) Licensees must cooperate in resolving co-channel and first-adjacent
   channel interference by changing channels used at specific cells or by other
   technical means.

   (2) Protection from capture of subscriber traffic is applied and limited in
   accordance with the following:

   (i) Subscriber traffic is captured if an SAB of one cellular system overlaps
   the CGSA of another operating cellular system. Therefore, cellular licensees
   must not begin to operate any facility that would cause an SAB to overlap
   the existing CGSA of another cellular system on the same channel block,
   without first obtaining the written consent of the licensee of that system.
   However, cellular licensees may continue to operate existing facilities that
   produce an SAB overlapping a subsequently-authorized portion of the CGSA of
   another cellular system on the same channel block until the licensee of that
   system requests that the SAB be removed from its CGSA. Such request may be
   made directly to the licensee of the overlapping system or to the FCC. In
   the event such request is made, the licensee of the overlapping system must
   reduce the transmitting power or antenna height (or both) at the pertinent
   cell site as necessary to remove the SAB from the CGSA of the other system,
   unless a written consent from the licensee of the other system allowing the
   SAB to remain is obtained. Cellular licensees may enter into contracts with
   the licensees of other cellular systems on the same channel block to allow
   SABs to overlap CGSAs.

   (ii) Cellular licensees are at most entitled to have a CGSA free of SABs
   from other cellular systems on the same channel block.

   (e) Unserved areas. Unserved areas are areas 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]