Goto Section: 22.653 | 22.659 | Table of Contents
FCC 22.657
Revised as of October 1, 2011
Goto Year:2010 |
2012
§ 22.657 Transmitter locations.
The purpose of the rules in paragraphs (a) and (b) of this section is
to define the areas in which the 470-512 MHz channels are allocated for
public mobile use. The purpose of the rules in paragraphs (c) through
(f) of this section is to reduce the likelihood that interference to
television reception from public mobile operations on these channels
will occur. The protected TV station locations specified in paragraphs
(d), (e)(1) and (f) of this section are the locations of record as of
September 1974, and these do not change even though the TV stations may
have been subsequently relocated.
(a) Base transmitter locations. Base transmitter locations must be
within 80 kilometers (50 miles) of the designated locations in this
paragraph. Mobile transmitters must not be operated at locations more
than 129 kilometers (80 miles) from the designated locations in this
paragraph. Note: All coordinates are referenced to North American Datum
1983 (NAD83).
Urban area N. latitude W. longitude
Houston, TX 29DEG45'26.8" 95DEG21'37.8"
New York, NY-NE NJ 40DEG45'06.4" 73DEG59'37.5"
(b) Mobile area of operation. Mobile transmitters must not be operated
at locations more than 48 kilometers (30 miles) from all associated
base stations.
(c) Protection from intermodulation interference. Base transmitter
locations must be at least 1.6 kilometers (1 mile) from the current
main transmitter locations of all TV stations transmitting on TV
channels separated by 2, 3, 4, 5, 7, or 8 TV channels from the TV
channel containing the frequencies on which the base station will
transmit. This requirement is intended to reduce the likelihood of
intermodulation interference.
(d) Adjacent channel protection from mobile transmitters. Base
transmitter locations must be at least 145 kilometers (90 miles) from
the applicable protected TV station locations specified in this
paragraph. This requirement is intended to provide a 0 dB minimum
desired to undesired signal strength ratio at the Grade B contour of an
adjacent channel TV station. Note: All coordinates are referenced to
North American Datum 1983 (NAD83).
Control transmitter frequency range Protected TV station location TV
channel
470-476 MHz Lancaster, PA, 40DEG15'45.3" N. Lat. 76DEG27'47.9" W. Long.
(15)
476-482 MHz Scranton, PA, 41DEG10'58.3" N. Lat. 75DEG52'19.7" W. Long.
(16)
(e) Co-channel protection from mobile transmitters. Base transmitter
locations must be at least the distance specified in paragraph (e)(2)
of this section from the applicable protected TV station locations
specified in paragraph (e)(1) of this section. This requirement is
intended to provide a 40 dB minimum desired to undesired signal
strength ratio at the Grade B contour of a co-channel TV station.
(1) The protected TV station locations are as follows (all coordinates
are referenced to North American Datum 1983 (NAD83)):
Control transmitter frequency range Protected TV station location
470-476 MHz Washington, DC, 38DEG57'17.4" N. Lat. 77DEG00'15.9" W.
Long.
476-482 MHz Lancaster, PA, 40DEG15'45.3" N. Lat. 76DEG27'47.9" W. Long.
(2) The required minimum distance depends upon the effective radiated
power (ERP) of the most powerful mobile transmitter(s) in the system:
Mobile unit ERP (watts) Minimum distance
Kilometers Miles
60 193 (120)
50 185 (115)
25 177 (110)
10 169 (105)
5 161 (100)
(f) Co-channel protection from base transmitters with high antennas.
This paragraph applies only to base transmitter locations in the New
York-Northeastern New Jersey urban area that utilize an antenna height
of more than 152 meters (500 feet) above average terrain. The distance
between the location of such a base transmitter and the applicable
protected TV station location specified in this paragraph must equal or
exceed the sum of the distance from the base transmitter location to
the radio horizon in the direction of the specified location and 89
kilometers (55 miles--representing the distance from the main
transmitter location of the TV station to its Grade B contour in the
direction of the base transmitter). The distance to the radio horizon
is calculated as follows:
[er14de98.026.gif]
Where d is the distance to the radio horizon in kilometers h is the
height of the antenna center of radiation above ground level in meters
Note: All coordinates are referenced to North American Datum 1983
(NAD83)):
Control transmitter frequency range Protected TV station location
470-476 MHz Washington, DC, 38DEG57'17.4" N. Lat. 77DEG00'15.9" W.
Long.
476-482 MHz Lancaster, PA, 40DEG15'45.3" N. Lat. 76DEG27'47.9" W. Long.
(g) The FCC may waive specific distance separation requirements of
paragraphs (d) through (f) of this section if the applicant submits an
engineering analysis which demonstrates that terrain effects and/or
operation with less effective radiated power would satisfy the
applicable minimum desired to undesired signal strength ratios at the
Grade B contours of the protected TV stations. For this purpose, the
Grade B contour of a TV station is deemed to be a circle with a 89
kilometer (55 mile) radius, centered on the protected TV station
location, and along which the median TV signal field strength is 64
dBuV/m. In any showing intended to demonstrate compliance with the
minimum desired to undesired signal ratio requirements of this section,
all predicted field strengths must have been determined using the UHF
TV propagation curves contained in part 73 of this chapter.
[ 59 FR 59507 , Nov. 17, 1994, as amended at 63 FR 68947 , Dec. 14, 1998]
Goto Section: 22.653 | 22.659
Goto Year: 2010 |
2012
CiteFind - See documents on FCC website that
cite this rule
Want to support this service?
Thanks!
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.
hallikainen.com
Helping make public information public