Goto Section: 74.643 | 74.651 | Table of Contents
Revised as of September 1, 2021
Goto Year:2020 |
§ 74.644 Minimum path lengths for fixed links.
(a) The distance between end points of a fixed link 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.
(MHz) Minimum path length
Below 1,990 n/a
Above 17,700 n/a
(b) For paths shorter than those specified in the Table, the EIRP shall
not exceed the value derived from the following equation.
EIRP = MAXEIRP−40 log(A/B) dBW
EIRP = The new maximum EIRP (equivalent isotropically radiated power)
MAXEIRP = Maximum EIRP as set forth in the Table in § 74.636 of this
A = Minimum path length from the Table above for the frequency band in
B = The actual path length in kilometers.
Note 1 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
Note 2 to paragraph (b): Stations licensed based on an application
filed before April 16, 2003, in the 2450-2483.5 MHz band, for EIRP
values exceeding those specified above, may continue to operate
indefinitely in accordance with the terms of their current
authorizations, subject to periodic renewal.
(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: Links authorized prior to April 1, 1987, are excluded from this
requirement, except that, effective April 1, 1992, the Commission will
require compliance with the criteria where an existing link would
otherwise preclude establishment of a new link.
[ 52 FR 7143 , Mar. 9, 1987, as amended at 68 FR 12771 , Mar. 17, 2003]
Goto Section: 74.643 | 74.651
Goto Year: 2020 |
CiteFind - See documents on FCC website that
cite this rule
Want to support this service?
Report errors in
this rule. Since these rules are converted to HTML by machine, it's possible errors have been made. Please
help us improve these rules by clicking the Report FCC Rule Errors link to report an error.
Helping make public information public