§  27.55   Power strength limits.

   (a) Field strength limits. For the following bands, the predicted or
   measured median field strength at any location on the geographical
   border of a licensee's service area shall not exceed the value
   specified unless the adjacent affected service area licensee(s)
   agree(s) to a different field strength. This value applies to both the
   initially offered service areas and to partitioned service areas.

   (1) 1995-2000 MHz, 2110-2155, 2155-2180, 2180-2200, 2305-2320, and
   2345-2360 MHz bands: 47 dBµV/m.

   (2) 600 MHz, 698-758, and 775-787 MHz bands: 40 dBµV/m.

   (3) The paired 1392-1395 MHz and 1432-1435 MHz bands and the unpaired
   1390-1392 MHz band (1.4 GHz band): 47 dBµV/m.

   (4) BRS and EBS: The predicted or measured median field strength at any
   location on the geographical border of a licensee's service area shall
   not exceed the value specified unless the adjacent affected service
   area licensee(s) agree(s) to a different field strength. This value
   applies to both the initially offered services areas and to partitioned
   services areas. Licensees may exceed this signal level where there is
   no affected licensee that is constructed and providing service. Once
   the affected licensee is providing service, the original licensee will
   be required to take whatever steps necessary to comply with the
   applicable power level at its GSA boundary, absent consent from the
   affected licensee.

   (i) Prior to transition, the signal strength at any point along the
   licensee's GSA boundary does not exceed the greater of that permitted
   under the licensee's Commission authorizations as of January 10, 2005
   or 47 dBµV/m.

   (ii) Following transition, for stations in the LBS and UBS, the signal
   strength at any point along the licensee's GSA boundary must not exceed
   47 dBµV/m. This field strength is to be measured at 1.5 meters above
   the ground over the channel bandwidth (i.e., each 5.5 MHz channel for
   licensees that hold a full channel block, and for the 5.5 MHz channel
   for licensees that hold individual channels).

   (iii) Following transition, for stations in the MBS, the signal
   strength at any point along the licensee's GSA boundary must not exceed
   the greater of -73.0 + 10 log(X/6) dBW/m2, where X is the bandwidth in
   megahertz of the channel, or for facilities that are substantially
   similar to the licensee's pre-transition facilities (including
   modifications that do not alter the fundamental nature or use of the
   transmissions), the signal strength at such point that resulted from
   the station's operations immediately prior to the transition, provided
   that such operations complied with paragraph (a)(4)(i) of this section.

   (b) Power flux density limit for stations operating in the 698-746 MHz
   bands. For base and fixed stations operating in the 698-746 MHz band in
   accordance with the provisions of § 27.50(c)(6), the power flux density
   that would be produced by such stations through a combination of
   antenna height and vertical gain pattern must not exceed 3000
   microwatts per square meter on the ground over the area extending to 1
   km from the base of the antenna mounting structure.

   (c) Power flux density limit for stations operating in the 746-757 MHz
   and 776-787 MHz bands. For base and fixed stations operating in the
   746-757 MHz and 776-787 MHz bands in accordance with the provisions of
   § 27.50(b)(6), the power flux density that would be produced by such
   stations through a combination of antenna height and vertical gain
   pattern must not exceed 3000 microwatts per square meter on the ground
   over the area extending to 1 km from the base of the antenna mounting
   structure.

   (d) Power flux density for stations operating in the 3700-3980 MHz
   band. For base and fixed stations operation in the 3700-3980 MHz band
   in accordance with the provisions of § 27.50(j), the power flux density
   (PFD) at any location on the geographical border of a licensee's
   service area shall not exceed -76 dBm/m2/MHz. This power flux density
   will be measured at 1.5 meters above ground. Licensees in adjacent
   geographic areas may voluntarily agree to operate under a higher PFD at
   their common boundary.

   [ 69 FR 5715 , Feb. 6, 2004, as amended at  69 FR 72034 , Dec. 10, 2004;  72 FR 27712 , May 16, 2007;  72 FR 48852 , Aug. 24, 2007;  73 FR 26040 , May 8,
   2008;  78 FR 8270 , Feb. 5, 2013;  78 FR 50256 , Aug. 16, 2013;  79 FR 599 ,
   Jan. 6, 2014;  79 FR 32413 , June 4, 2014;  79 FR 48539 , Aug. 15, 2014;  85 FR 22882 , Apr. 23, 2020]