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a Field strengths from fixed transmitters, such as base stations for radio (cellular/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 should be
considered. If the measured field strength in the location in which the device is used exceeds
the applicable RF compliance level above, the device should be observed to verify normal
operation. If abnormal performance is observed, additional measures may be necessary, such
as reorienting or relocating the device.
b Over the frequency range 150 kHz to 80 MHz, field strengths should be less than 3 V/m.
• Recommended separation distances between portable and mobile RF communication
equipment and the device.
The device is intended for use in an electromagnetic environment in which radiated
RF disturbances are controlled. The customer or the user of the device can help
electromagnetic interference by maintaining a minimum distance between portable and
mobile RF communications equipment (transmitters) and the device as recommended
below, according to the maximum output power of the communications equipment.
Rated maximum
output power of
transmitter
(W)
Separation distance according to frequency of transmitter (m)
150 kHz to 80
MHz
d = 3.5
80 MHz to 800
MHz
d = 1.2
800 MHz to 2.7 GHz
d = 2.3
0.01
0.12
0.12
0.23
0.1
0.38
0.38
0.73
1
1.2
1.2
2.3
10
3.8
3.8
7.3
100
12
12
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For transmitters rated at a maximum output power not listed above, the recommended separation
distance d in metres (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.
