Attachment Exhibit B

This document pretains to SES-MOD-20151203-00909 for Modification on a Satellite Earth Station filing.

IBFS_SESMOD2015120300909_1117147

                                           FCC Form 312
                                             Exhibit B
                                  RF Hazard Analysis of the Terminal


Analysis of Non-Ionizing Radiation for MT2220 Earth Station Antenna System

This report analyzes the non-ionizing radiation levels for the MT2220 earth station antenna system.

The FCC’s Office of Engineering Technology’s Bulletin No. 65 specifies that there are two separate
tiers of exposure limits that are dependent upon the situation in which the exposure takes place and/or
the status of the individuals who are subject to the exposure. The two tiers are General Population /
Uncontrolled environment, and an Occupational / Controlled environment.

The applicable exposure limit for the General Population / Uncontrolled environment, i.e., areas that
people may enter freely, at this frequency of operation is 1 mW/cm2 average power density over a 30
minute period.

The applicable exposure limit for the Occupational / Controlled environment, i.e., areas that only
authorized / trained personnel have access to, at this frequency of operation is 5 mW/cm2 average power
density over a 6 minute period.


Summary of expected radiation levels for an Uncontrolled environment


Region                                Maximum Power Density                 Hazard Assessment

Safe region range (R) ≥ 0.44 m                1.0 mW/cm2                    Satisfies FCC MPE

Far field (Rff) = 0.13 m                      11.3 mW/cm2                   Potential Hazard



Conclusions

The proposed earth station system will be mounted on the top of a vehicle. During operation, the user will
be greater than 0.44 m (17.6 inches) away from the unit. The maximum gain (used in this analysis) occurs
at a 90 degree elevation angle and is reduced significantly at an elevation angle of 15 degrees or less. At
the edge of far field region, a PFD of 11.3 mW/cm2 is obtained, decaying rapidly to 1 mW/cm2 at a
distance of 0.44m (17.6 inches) from the antenna axis. Power decays dramatically from that point towards
personnel near or inside the vehicle, remaining below hazardous PSD levels

Based on the above analysis it is concluded that no hazard exists for the public.


Analysis

The analysis and calculations that follow in this report are performed in compliance with
the methods described in the OET Bulletin No. 65.

Definition of terms

The terms are used in the formulas here are defined as follows:
S = power density at the specified distance
Rff = distance to the beginning of the far-field
R = 0.44 m (17.6 in)          distance to point of interest
P = 6.3W                      power fed to the antenna in Watts
D = 0.2 m                     effective diameter of antenna array
G=4                           power gain relative to an isotropic radiator
F = 1660.5                    frequency in MHz
λ = 0.181 m                   wavelength in meters (300/MHz)

Figure 1 illustrates a typical configuration in which the antenna is installed on top on a
vehicle. The exact mounting location will vary depending on the vehicle. It will be shown
in this report for this analytical case that the RF exposure hazard environment is benign
for personnel on the ground or in the vehicle.


..




             Figure 1: MT2220/Explore 122 Mobile SATCOM Terminal


Far-Field Region. The power density in the far-field or Fraunhofer region of the
antenna pattern decreases inversely as the square of the distance. The distance to the start
of the far field can be calculated by the following equation:

Rff    = (0.6 * D2) / λ.

       = (0.6 * (0.2 m)2) / 0.181 m =

       0.13 m

The power density at the start of the far-field region of the radiation pattern can be
estimated by the equation:

Sff    = (P * G) / (4 * π * Rff )2




       = (6.3 W * 4) / (4 * π * (0.13 m)2) = 11.3 mW/cm2


The power density at the point of interest in the far-field region of the radiation pattern
can be estimated by the equation:

Sff    = (P * G) / (4 * π* R2)

       = (1.5 W * 4) / (4 * π * (0.45 m)2) =

       0.999 mW/cm    2



Document Created: 0660-04-14 00:00:00
Document Modified: 0660-04-14 00:00:00

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