§  101.143   Minimum path length requirements.

   (a) The distance between end points of a fixed link in the private
   operational fixed point-to-point and the common carrier fixed
   point-to-point microwave services must equal or exceed the value set
   forth in the table below or the EIRP must be reduced in accordance with
   the equation set forth below:
   Frequency band (MHz) Minimum path length (km)
   Below 1,850                               N/A
   1,850 to 7,125                             17
   10,550 to 13,250                            5
   Above 17,700                              N/A

   (b) For paths shorter than those specified in the table in paragraph
   (a) of this section, the EIRP shall not exceed the value derived from
   the following equation:

   EIRP = MAXEIRP-40*log(A/B) dBW

   Where: EIRP = The new maximum EIRP (equivalent isotropically radiated
   power) in dBW. MAXEIRP = Maximum EIRP as set forth in the Table in
   Section 101.113(a).

   A = Minimum path length from the Table above for the frequency band in
   kilometers.

   B = The actual path length in kilometers.

   Note to paragraph (b): For transmitters using Automatic Transmitter
   Power Control, EIRP corresponds to the maximum transmitter power
   available, not the coordinated transmit power or the nominal transmit
   power.

   (c) Upon an appropriate technical showing, applicants and licensees
   unable to meet the minimum path length requirement may be granted an
   exception to these requirements.

   Note to paragraph (c): Links authorized prior to April 1, 1987, need
   not comply with this requirement.

   [ 61 FR 26677 , May 28, 1996, as amended at  65 FR 38330 , June 20, 2000]