User guide

Canopy System User Guide Exposure Separation Distances

pmp-0229 (Mar 2013)

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Details of Exposure Separation Distances Calculations and

Power Compliance Margins

Limits and guidelines for RF exposure come from:

• US FCC limits for the general population. See the FCC web site at http://www.fcc.gov

, and

the policies, guidelines, and requirements in Part 1 of Title 47 of the Code of Federal

Regulations, as well as the guidelines and suggestions for evaluating compliance in FCC OET

Bulletin 65.

• Health Canada limits for the general population. See the Health Canada web site at

http://www.hc-sc.gc.ca/rpb

and Safety Code 6.

• ICNIRP (International Commission on Non-Ionizing Radiation Protection) guidelines for the

general public. See the ICNIRP web site at http://www.icnirp.de/ and Guidelines for Limiting

Exposure to Time-Varying Electric, Magnetic, and Electromagnetic Fields.

The applicable power density exposure limits from the documents referenced above are

• 6 W/m

for RF energy in the 900-MHz frequency band in the US and Canada.

• 10 W/m

for RF energy in the 2.4-, 5.2-, 5.4-, and 5.7-GHz frequency bands.

Peak power density in the far field of a radio frequency point source is calculated as follows:

S =

P ⋅ G

where

S = power density in W/m

P = RMS transmit power capability of the radio, in W

G = total Tx gain as a factor, converted from dB

d = distance from point source, in m

Rearranging terms to solve for distance yields

d =

P ⋅ G

Table 44 shows calculated minimum separation distances d, recommended distances and resulting

power compliance margins for each frequency band and antenna combination.