Sec.  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]