Motorola Solutions Inc. 99FT4100 Manual De Usuario

where 

is the free-space wavenumber and L is the effective antenna length yielding

the appropriate vertical beamwidth, while H is the antenna height above ground and d is the point of
interest (POI) distance from the vertical antenna projection to ground (see the following figure). The
multiplicative factor 2.56 is introduced to enforce near-perfect, in-phase ground reflection as
recommended in [2]. In this case, spatial averaging is not carried out to make the EME exposure
assessment more conservative.

The SLR 1000 Repeater operates in different frequency ranges with different channels transmitting 10
W radio frequency (RF) power.

The typical system configuration comprises an omnidirectional array antenna featuring 6–10 dBd gain,
installed at or above 20 m from ground level, and fed by the repeater through a combiner characterized
by a typical 3 dB transmission loss, and a 30 m 7/8" coaxial cable characterized by a typical 2.7 dB/
100m loss, resulting in a total 3.9 dB transmission loss. Based on these characteristics, the RF power
at the antenna input is about 20 W.

Since shorter antennas provide a conservative EME exposure assessment from equation (1), when

, the parameters of a typical 6.6 dBd antennas are employed (it has to be verified that the

resulting compliance distances are indeed smaller than 

). Such an antenna (such as, Andrew

DB408) would exhibit a typical elevation beamwidth of about 14 degrees.

Guidelines are used for the EME exposure assessment.

Based on the operating frequency range, the most conservative power density limits are those defined
in the ICNIRP guidelines [1]. The guidelines are 10.1 W/m

2

 for occupational exposure, and 2.02 W/m

2

for general public exposure.

MN003557A01-AA
Appendix E: MOTOTRBO Repeater EME Assessment

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