§ 101.113   Transmitter power limitations.

   (a) On any authorized frequency, the average power delivered to an antenna
   in this service must be the minimum amount of power necessary to carry out
   the communications desired. Application of this principle includes, but is
   not to be limited to, requiring a licensee who replaces one or more of its
   antennas with larger antennas to reduce its antenna input power by an amount
   appropriate  to  compensate for the increased primary lobe gain of the
   replacement  antenna(s).  In  no  event  shall  the average equivalent
   isotropically radiated power (EIRP), as referenced to an isotropic radiator,
   exceed the values specified below. In cases of harmful interference, the
   Commission may, after notice and opportunity for hearing, order a change in
   the effective radiated power of this station. Further, the output power of a
   transmitter on any authorized frequency in this service may not exceed the
   following:
   Frequency band (MHz) Maximum allowable EIRP^1 2
                        Fixed^1 2 (dBW) Mobile (dBW)
   928.0-929.0(2)       + 17           
   932.0-932.5(2)       + 17           
   932.5-935.0          + 40           
   941.0-941.5(2)       + 30            + 14
   941.5-944.0          + 40           
   952.0-960.0(2)       + 40            + 14
   1,850-1,990          + 45           
   2,110-2,150          + 45           
   2,150-2,180^3        + 45           
   2,180-2,200          + 45           
   2,450-2,500          + 45           
   2,500-2,686                         
   2,686-2,690          + 45           
   3,700-4,200          + 55           
   5,925-6,425          + 55           
   6,425-6,525                          + 35
   6,525-6,875          + 55           
   6,875-7,125          + 55           
   10,550 to 10,600^5   + 55           
   10,600 to 10,680^5   + 40           
   10,700-11,700        + 55           
   12,200-12,700^11     + 50           
   12,700-13,200^4      + 50           
   13,200-13,250^4      + 55           
   14,200-14,400^12     + 45           
   17,700-18,600        + 55           
   18,600-18,800^6      + 35           
   18,800-19,700        ^5 + 55        
   21,200-23,600^10     + 55           
   24,250-25,250        ^5+ 55         
   27,500-28,350^9      + 55           
   29,100-29,250        (^7)           
   31,000 to 31,075^8 9 30 dBW/MHz      30 dBW/MHz
   31,075 to 31,225^8 9 30 dBW/MHz      30 dBW/MHz
   31,225 to 31,300^8 9 30 dBW/MHz      30 dBW/MHz
   38,600-40,000        + 55           
   71,000-76,000^13     + 55            + 55
   81,000-86,000^13     + 55            + 55
   92,000-95,000        + 55            + 55

   ^1Per polarization.

   ^2For multiple address operations, see § 101.147. Remote alarm units that are
   part of a multiple address central station projection system are authorized
   a maximum of 2 watts.

   ^3When an omnidirectional antenna is authorized in the 2150-2160 MHz band,
   the maximum power shall be 60 dBm.

   ^4Also see § 101.145.

   ^5The output power of a DEMS System nodal transmitter shall not exceed 0.5
   watt per 250 kHz. The output power of a DEMS System user transmitter shall
   not exceed 0.04 watt per 250 kHz. The transmitter power in terms of the
   watts specified is the peak envelope power of the emission measured at the
   associated antenna input port. The operating power shall not exceed the
   authorized power by more than 10 percent of the authorized power in watts at
   any time. Frequencies from 10,600-10,680 MHz are subject to footnote US265
   in the Table of Frequency Allocations in § 2.106 of the Commission's Rules.
   Stations authorized prior to April 1, 2003 to exceed the 40 dBW limit may
   continue to operate at their authorized output power level indefinitely,
   provided that neither end point of the relevant link is relocated.

   ^6Maximum power delivered to the antenna shall not exceed -3 dBw.

   ^7See § 101.113(c).

   ^8For  stations  authorized prior to March 11, 1997, and for non-Local
   Multipoint Distribution Service stations authorized pursuant to applications
   refiled no later than June 26, 1998, the transmitter output power shall not
   exceed 0.050 watt.

   ^9For subscriber transceivers authorized in these bands, the EIRP shall not
   exceed 55 dBw or 42 dBw/MHz.

   ^10See § 101.147(s).

   ^11The EIRP for MVDDS stations is limited to 14.0 dBm per 24 MHz (−16.0 dBW
   per 24 MHz). Incumbent point-to-point stations may use up to + 50 dBW except
   for low power systems which were licensed under § 101.147(q).

   ^12Beginning March 1, 2005, no new LTTS operators will be licensed and no
   existing LTTS licensees will be renewed in the 14.2-14.4 GHz band.

   ^13The maximum transmitter power is limited to 3 watts (5 dBW) unless a
   proportional  reduction  in  maximum authorized EIRP is required under
   § 101.115. The maximum transmitter power spectral density is limited to 150
   mW per 100 MHz.

   (b) The power of transmitters that use Automatic Transmitter Power Control
   shall not exceed the power input or output specified in the instrument of
   station  authorization.  The  power  of non-ATPC transmitters shall be
   maintained as near as practicable to the power input or output specified in
   the instrument of station authorization.

   (c)(1)  Transmitter  power limitations. Point-to-point stations in the
   29.1-29.25 GHz band for the LMDS backbone between LMDS hubs shall be limited
   to a maximum allowable e.i.r.p. density per carrier of 23 dBW/MHz in any one
   megahertz in clear air, and may exceed this limit by employment of adaptive
   power control in cases where link propagation attenuation exceeds the clear
   air value due to precipitation and only to the extent that the link is
   impaired.

   (2) Hub transmitter EIRP spectral area, density limit. LMDS applicants shall
   demonstrate  that,  under  clear air operating conditions, the maximum
   aggregate of LMDS transmitting hub stations in a Basic Trading Area in the
   29.1-29.25 GHz band will not transmit a co-frequency hub-to-subscriber
   e.i.r.p. spectral area density in any azimuthal direction in excess of X
   dBW/(MHz-km2) when averaged over any 4.375 MHz band, where X is defined in
   Table 1. Individual hub stations may exceed their clear air e.i.r.p.s by
   employment  of  adaptive power control in cases where link propagation
   attenuation exceeds the clear air value and only to the extent that the link
   is impaired.

   (i) The e.i.r.p. aggregate spectral area density is calculated as follows:
   eCFR graphic er28au96.732.gif

   View or download PDF

   where:

   N = number of co-frequency hubs in BTA.

   A = Area of BTA in km2.

   pi = spectral power density into antenna of i-th hub (in W/MHz).

   gi = gain of i-th hub antenna at zero degree elevation angle.

   Each pi and gi are in the same 1 MHz within the designated frequency band.

   (ii) The climate zones in Table 1 are defined for different geographic
   locations  within  the  US  as  shown  in Appendix 28 of the ITU Radio
   Regulations.

   Table 1^1
   Climate zone e.i.r.p. Spectral Density (Clear Air) (dBW/MHz-km^2)^2
        1                                 −23
        2                                 −25
      3,4,5                               −26

   ^1LMDS system licensees in two or more BTAs may individually or collectively
   deviate from the spectral area density computed above by averaging the power
   over any 200 km by 400 km area, provided that the aggregate interference to
   the satellite receiver is no greater than if the spectral area density were
   as specified in Table 1. A showing to the Commission comparing both methods
   of  computation is required and copies shall be served on any affected
   non-GSO 20/30 GHz MSS providers.

   ^2See § 21.1007(c)(i) for the population density of the BTA.

   (3) Hub transmitter e.i.r.p. spectral area density limit at elevation angles
   above the horizon. LMDS applicants shall demonstrate that, under clear air
   operating  conditions,  the maximum aggregate of LMDS transmitting hub
   stations  in  a Basic Trading Area in the 29.1-29.25 GHz band will not
   transmit a co-frequency hub-to-subscriber e.i.r.p. spectral area density in
   any azimuthal direction in excess of X dBW/(MHz-km2) when averaged over any
   4.375 MHz band where X is defined in Table 2. Individual hub stations may
   exceed their clear air e.i.r.p.s by employment of adaptive power control in
   cases where link propagation attenuation exceeds the clear air value and
   only to the extent that the link is impaired.

   (i) The e.i.r.p. aggregate spectral area density is calculated as follows:
   eCFR graphic er28au96.733.gif

   View or download PDF

   where:

   N = number of co-frequency hubs in BTA.

   A = Area of BTA in km2.

   e.i.r.p. (ai) = equivalent isotropic radiated spectral power density of the
   i-th hub (in W/MHz) at elevation angle a where a is the angle in degrees of
   elevation above horizon. e.i.r.p.(0°) is the hub e.i.r.p. area density at
   the horizon used in Section 101.113c(2). The nominal antenna pattern will be
   used for elevation angles between 0° and 8°, and average levels will be used
   for angles beyond 8°, where average levels will be calculated by sampling
   the antenna patterns in each 1° interval between 8° and 9015, dividing by
   83.

   Table 2
   Elevation angle (a) Relative e.i.r.p. density (dBW/MHz-km^2)
   0° ≤a ≤4.0° e.i.r.p.(a) = e.i.r.p.(0°) + 20 log (sinΠ x)(1/Π x) where x = (a
   + 1)/7.5°.
   4.0° 7.7° e.i.r.p.(a) = e.i.r.p.(0°) - 22.

   (ii)  LMDS  system  licensees  in two or more BTAs may individually or
   collectively  deviate from the spectral area density computed above by
   averaging  the power over any 200 km by 400 km area, provided that the
   aggregate interference to the satellite receiver is no greater than if the
   spectral  area  density were as specified in Table 1. A showing to the
   Commission comparing both methods of computation is required and copies
   shall be served on any affected non-GSO MSS providers.

   (4) Power reduction techniques. LMDS hub transmitters shall employ methods
   to  reduce  average  power levels received by non-geostationary mobile
   satellite receivers, to the extent necessary to comply with paragraphs
   (c)(1) and (c)(2) of this section, by employing the methods set forth below:

   (i) Alternate polarizations. LMDS hub transmitters in the LMDS service area
   may employ both vertical and horizontal linear polarizations such that 50
   percent (plus or minus 10 percent) of the hub transmitters shall employ
   vertical polarization and 50 percent (plus or minus 10 percent) shall employ
   horizontal polarization.

   (ii) Frequency interleaving. LMDS hub transmitters in the LMDS service area
   may employ frequency interleaving such that 50 percent (plus or minus 10
   percent) of the hub transmitters shall employ channel center frequencies
   which  are different by one-half the channel bandwidth of the other 50
   percent (plus or minus 10 percent) of the hub transmitters.

   (iii) Alternative methods. As alternatives to paragraphs (c)(4)(i) and
   (c)(4)(ii) of this section, LMDS operators may employ such other methods as
   may be shown to achieve equivalent reductions in average power density
   received by non-GSO MSS satellite receivers.

   [ 61 FR 26677 , May 28, 1996]

   Editorial Note: For Federal Register citations affecting § 101.113, see the
   List of CFR Sections Affected, which appears in the Finding Aids section of
   the printed volume and at www.fdsys.gov.

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