§ 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.

   return arrow Back to Top