Afar AR24027, Руководство оператора

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AR24027 Operator’s Manual
3-9
instructs the radio to dwell on the specified channel for the specified amount of time. After taking
several samples the radio displays the signal level detected in that channel over time.
3.2.8 Output Power Limits (FCC)
The Federal Communications Commission (FCC) regulations limit the maximum Effective Isotropic
Radiated Power (EIRP) for spread spectrum systems operating in the 2.4 GHz band. Close to the band
edges, the output power must be limited to avoid spilling over into the FCC protected band from
2.4835 GHz to 2.500 GHz. The table below takes these considerations into account and shows the
maximum allowed output power for the various antennas
Maximum Output Power (dBm)
Channel Frequency Antenna Gain
(MHz) 9 dBi 18 dBi 24 dBi
3 to 19 23 23 23
20 2440.0 23 23 21
21 to 33 23 23 23
34 2468.0 23 23 22
35 2470.0 23 22 21
36 2472.0 23 21 20
37 2474.0 22 19 10
3.2.9 Output Power Limits (CE)
The European Telecommunications Standards Institute (ETSI) regulations impose a limit of 20 dBm
as the maximum Effective Isotropic Radiated Power (EIRP) for direct sequence spread spectrum
systems operating in the 2.4 GHz band. In addition the maximum spectral power density is limited to
10 dBm per MHz maximum EIRP. Of these two limits the power density is the most restrictive for
this radio. The installer must reduce the output power of the
AR24027 so that the EIRP of the radio
does not exceed 10 dBm. The antenna gain, cable and connector losses must be taken into account
when computing the maximum output power.
3.2.10 Maximum Permissible Exposure (MPE) Limitations
The installer must mount all transmit antennas so as to comply with the limits for human exposure to
radio frequency (RF) fields per paragraph 1.1307 of the FCC Regulations . The FCC requirements
incorporate limits for Maximum Permissible Exposure (MPE) in terms of electric field strength,
magnetic field strength, and power density.
Antenna installations must be engineered so that MPE is limited to 1 mW/cm
2
, the more stringent
limit for "uncontrolled environments". The table below specifies the minimum distance that must be
maintained between the antenna and any areas where persons may have access, including rooftop
walkways, sidewalks, as well as through windows and other RF-transparent areas behind which
persons may be located.