Attachment Exhibit B

This document pretains to SES-MOD-20170706-00732 for Modification on a Satellite Earth Station filing.

IBFS_SESMOD2017070600732_1235734

Radiation Hazard Report Exhibit B Page 1 of 5 Analysis of Non-Ionizing Radiation for a 0.75-Meter Flexible Earth Station Antenna System This report analyzes the non-ionizing radiation levels for a 0.75-meter flexible earth station system. The analysis and calculations performed in this report comply with the methods described in the FCC Office of Engineering and Technology Bulletin No. 65, first published in 1985 and revised in 1997 in Edition 97-01.The radiation safety limits used in the analysis are in conformance with the FCC R&O 96-326. Bulletin No. 65 and the FCC R&O specifies that there are two separate tiers of exposure limits that are dependent on the situation in which the exposure takes place and/or the status of the individuals who are subject to the exposure. The Maximum Permissible Exposure (MPE) limits for persons in a General Population/Uncontrolled environment are shown in Table 1. The General Population/Uncontrolled MPE is a function of transmit frequency and is for an exposure period of thirty minutes or less. The MPE limits for persons in an Occupational/Controlled environment are shown in Table 2. The Occupational MPE is a function of transmit frequency and is for an exposure period of six minutes or less. The purpose of the analysis in this report is to determine the power flux density levels of the earth station in the far-field, near-field, transition region, between the feed and reflector surface, at the reflector surface, between the antenna edge and the ground, and off-axis in the near-field, and to compare these levels to the specified MPEs. Table 1. Limits for General Population/Uncontrolled Exposure (MPE) Frequency Range (MHz) Power Density (mW/cm2) Averaging Time (minutes) 30 - 300 0.2 30 300 - 1500 Frequency [MHz] / 1500 30 1500 - 100000 1.0 30 Table 2. Limits for Occupational/Controlled Exposure (MPE) Frequency Range (MHz) Power Density (mW/cm2) Averaging Time (minutes) 30 - 300 1.0 6 300 - 1500 Frequency [MHz] / 300 6 1500 - 100000 5.0 6 Table 3. Formulas and Parameters Used for Determining Power Flux Densities Parameter Symbol Formula Value Units Antenna Diameter D Input 0.75 m Antenna Surface Area Asurface π ∙ D2 /4 0.442 m2 Feed Flange Diameter Dfa Input 6.5 cm Area of Feed Flange Afa π ∙ Dfa 2 /4 33.183 cm2 Frequency F Input 14250 MHz Wavelength λ c/F 0.02104 m Transmit Power P Input 15 Watts Antenna Gain (dBi) Ges Input 38.8 dBi Antenna Gain (factor) G 10Ges /10 7.534 ∙ 103 - Antenna Efficiency η G ∙ λ2 /(π2 ∙ D2 ) 0.60060 - Pi π Constant 3.14159265 - Speed of Light c Constant 2.9979 ∙ 108 m/s GATR Technologies, Inc.

Radiation Hazard Report Exhibit B Page 2 of 5 1. Far Field Calculation The distance to the beginning of the Far Field can be determined from the following equation: 0.60∙D2 Distance to the Far Field Region R ff = = 16.042 m (1) λ The maximum main beam power density in the Far Field can be determined from the following equation: G∙P mW On-Axis Far Field Power Density Sff = 2 = 34.94 mW2 = 3.494 (2) 4∙π∙Rff cm2 2. Near Field Calculation Power flux density is considered to be at a maximum value throughout the entire length of the defined Near Field region. The region is contained within a cylindrical volume having the same diameter as the antenna. Past the boundary of the Near Field region, the power density from the antenna decreases linearly with respect to increasing distance. The distance to the end of the Near Field can be determined from the following equation: D2 Extent of the Near Field R nf = = 6.684 m (3) 4∙λ The maximum main beam power density in the Near Field can be determined from the following equation: 16.0∙η∙P mW On-Axis Near Field Power Density Snf = = 81.57 mW2 = 8.157 (4) π∙D2 cm2 3. Transition Region Calculation The Transition region is located between the Near and Far Field regions. The power density begins to decrease linearly with increasing distance in the Transition region. While the power density decreases inversely with distance in the Transition region, the power density decreases inversely with the square of the distance in the Far Field region. The maximum power density in the Transition region will not exceed that calculated for the Near Field region. The power density calculated in Section 1 is the highest power density the antenna can produce in any of the regions away from the antenna. The power density at a distance Rt can be determined from the following equation: Snf ∙Rnf mW Transition Region Power Density St = = 8.157 cm 2 (5) Rt GATR Technologies, Inc.

Radiation Hazard Report Exhibit B Page 3 of 5 4. Region between the Feed Assembly and the Antenna Reflector Transmissions from the feed assembly are directed toward the antenna reflector surface, and are confined within a hemispherical shape defined by the type of feed assembly. The energy between the feed assembly and reflector surface can be calculated by determining the power density at the feed assembly surface. This can be determined form the following equation: 4000∙P mW Power Density at the Feed Flange Sfa = = 1808 (6) Afa cm2 5. Main Reflector Region The power density in the main reflector is determined in the same manner as the power density at the feed assembly. The area is now the area of the reflector aperture and can be determined from the following equation: 4∙P mW Power Density at the Reflector Surface Ssurface = = 13.581 (7) Asurface cm2 6. Region between the Reflector and the Ground Assuming uniform illumination of the reflector surface, the power density between the antenna and the ground can be determined from the following equation: P mW Power Density between Reflector and Ground Sg = = 3.395 (8) Asurface cm2 7. Near Field Off-Axis Calculation For off-axis calculations in the near-field and in the transition region, it can be assumed that, at distances of at least one diameter removed from the center of the main beam, the power density will be a least 20 dB less than the value calculated for the equivalent distance in the main beam. Therefore, for off-axis regions at least 4 meters away from the center of the main beam, the power density can be determined from the following equation: mW Off-Axis Near Field Power Density Snf−offa = Snf − 20dB = 0.08157 cm 2 (9) GATR Technologies, Inc.

Radiation Hazard Report Exhibit B Page 4 of 5 8. Summary of Calculations Table 4. Summary of Expected Radiation Levels for Uncontrolled Environment Calculated Maximum Radiation Region Power Density Level Hazard Assessment (mW/cm2) 1. Far Field (R t ≥ R ff = 456.316 m) Sff 3.494 Potential Hazard 2. Near Field (R t ≤ R nf = 190.132 m) Snf 8.157 Potential Hazard 3. Transition Region (R nf < R t < R ff ) St 8.157 Potential Hazard 4. Between Feed Assembly and Sfa 1808.154 Potential Hazard Antenna Reflector 5. Main Reflector Ssurface 13.581 Potential Hazard 6. Between Reflector and Ground Sg 3.395 Potential Hazard 7. Off-Axis Near Field Snf−offa 0.082 Satisfies FCC MPE Table 5. Summary of Expected Radiation Levels for Controlled Environment Calculated Maximum Radiation Region Power Density Level Hazard Assessment (mW/cm2) 1. Far Field (R t ≥ R ff = 456.316 m) Sff 3.494 Satisfies FCC MPE 2. Near Field (R t ≤ R nf = 190.132 m) Snf 8.157 Potential Hazard 3. Transition Region (R nf < R t < R ff ) St 8.157 Potential Hazard 4. Between Feed Assembly and Sfa 1808.154 Potential Hazard Antenna Reflector 5. Main Reflector Ssurface 13.581 Potential Hazard 6. Between Reflector and Ground S g 3.395 Satisfies FCC MPE 7. Off-Axis Near Field Snf−offa 0.082 Satisfies FCC MPE 9. Conclusions Based upon the above analysis, it is concluded that FCC RF Guidelines have been exceeded in the specified region(s) of Table 4 and Table 5. The applicant proposes to comply with the MPE limits by one or more of the following methods. The applicant will ensure that the main beam of the antenna will be pointed at least one diameter (0.75 meters) away from any buildings or other obstacles in those areas that exceed the MPE levels. The area around the antenna equal to one diameter removed from the main beam will be secured off, and public access will be denied. This distance satisfies the FCC MPE for both Controlled and Uncontrolled Environments. In addition, radiation hazard decals attached to the antenna radome will further indicate to the general public the potential hazard associated closer to the antenna. All operating personnel will be trained and made aware of the human exposure levels at and around the earth station. Specifically, concerning Region 4: due to the Antenna Reflector being confined to a radome that also contains the feed assembly, the region between the Feed Assembly and Antenna GATR Technologies, Inc.

Radiation Hazard Report Exhibit B Page 5 of 5 Reflector is not physically accessible without disassembly of the system. Furthermore, the earth station’s operating personnel will not require access to this area while the earth station is in operation, and the transmitter will be turned off during any antenna maintenance. The applicant agrees to abide by the conditions specified in Condition 5208 provided below: Condition 5208 – The licensee shall take all necessary measures to ensure that the antenna does not create potential exposure of humans to radiofrequency radiation in excess of the FCC exposure limits defined in 47 CFR §§1.1307(b) and 1.1310 wherever such exposures might occur. Measures must be taken to ensure compliance with limits for both occupational/controlled exposure and for general population/uncontrolled exposure, as defined in these rule sections. Compliance can be accomplished in most cases by appropriate restrictions such as fencing. Requirements for restrictions can be determined by predictions based on calculations, modeling or by field measurements. The FCC’s OET Bulletin 65 (available on-line at www.fcc.gov/oet/rfsafety) provides information on predicting exposure levels and on methods for ensuring compliance, including the use of warning and alerting signs and protective equipment for workers. GATR Technologies, Inc.


Document Created: 2017-06-08 13:45:02
Document Modified: 2017-06-08 13:45:02
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