Recommended Separation Distances Between Portable and Mobile
RF Communication Equipment and system
The system is intended for use in an electromagnetic environment in which
radiated RF disturbances are controlled. The user of the system can help prevent
electromagnetic interference by maintaining a minimum distance between
portable and mobile RF communications equipment (transmitters and the
system as recommended below, according to the maximum output power of the
communication equipment.
Rated maximum
output power (W)
of transmitter
Separation distance (m) according to
frequency of transmitter
150 kHZ to 80 MHz
d = 1.17√P
80 MHz to 800 MHZ
d = 1.17√P
800 MHz to 2.7 GHz
d = 2.33√P
0.01
0.12 m
0.12 m
0.23 m
0.1
0.37 m
0.37 m
0.74 m
1
1.17 m
1.17 m
2.33 m
10
3.70 m
3.70 m
7.37 m
100
11.7 m
11.7 m
23.3 m
For transmitters rated at a maximum output power not listed above, the recommended
separation distance (d) in meters (m) can be estimated using the equation applicable
to the frequency of the transmitter, where P is the maximum output power rating of the
transmitter in watts (W) according to the transmitter manufacturer.
Note 1: At 80 MHz and 800 MHz, the separation distance for the higher frequency
range applies.
Note 2: These guidelines may not apply in all situations. Electromagnetic propagation
is affected by absorption and reflection from structures, objects and people.
a) Field strengths from fixed transmitters, such as base stations for radio (celluar/
cordless) telephones and land mobile radios, amateur radio, AM and FM radio
broadcast, and TV broadcast, cannot be predicted theoretically with accuracy.
To assess the electromagnetic environment due to fixed RF transmitters, an
electromagnetic site survey shall be considered. If the measured field strength in
the location in which the system is used exceeds the applicable RF compliance
level above, the system shall be observed to verify normal operation. If abnormal
performance is observed, additional measures may be necessary, such as
reorienting or relocating the system.
b) Over the frequency range 150 kHz to 80 MHz, field strengths shall be less than 3 V/m.
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