Attachment ATTACHED ONE

ATTACHED ONE

REQUEST FOR SUPPLEMENTAL INFORMATION submitted by Christine A. Reilly

ATTACHED ONE

2003-09-30

This document pretains to SES-LIC-20030904-01219 for License on a Satellite Earth Station filing.

IBFS_SESLIC2003090401219_336645

ATTACHMENT B Page 1 of 5 Analysis of Non—Tonizing Radiation for a 7.0 Meter Earth Station System This report analyzes the non—ionizing radiation levels for a 7.0 meter earth station system. The analysis and calculations performed in this report are in compliance 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 dependant 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 described 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 subreflector or feed and main reflector surface, at the main reflector surface, and between the antenna edge and the ground and to compare these levels to the specified MPEs. Table 1. Limits for General Population/Uncontrolled Exposure (MPE) Frequency Range (MHz) Power Density (mWatts/om**2) 30—300 0.2 300—1500 Frequency (MHz) * (0 . 8/1200) 1500—100, 000 1.0 Table 2. Limits for Occupational/Controlled Exposure (MPE) Frequency Range (MHZz) Power Density (mWatts/cm**2) 30—300 1.0 300—1500 Frequency (MHz) * (4 . 0/1200) 1500—100, 000 5.0 Table 3 contains the parameters that are used to calculate the various power densities for the earth stations.

ATTACHMENT B Page 2 of 5 Table 3. Formulas and Parameters Used for Determining Power Flux Densities Parameter Abbreviation Value Units Antenna Diameter D 7.0 meters Antenna Surface Area Sa II * D**2/4 meters**2 Subreflector Diameter Ds 60. 0 cm Area of Subreflector As II * Ds**2/4 cm**2 Frequency Frequency 6175 MHz Wavelength lambda 300 /frequency (MHz) meters Transmit Power P 500. 00 Watts Antenna Gain Ges 51.1 aBi pi II 3.1415927 n/a Antenna Efficiency n 0.63 n/a 1. Far Field Distance Calculation The distance to the beginning of the far field can be determined from the following equation: (1) Distance to the Far Field Region, (Rf) = 0.60 * D**2 / lambda (1) 605.1 meters n The maximum main beam power density in the Far Field can be determined from the following equation: (2) On—Axis Power Density in the Far Field, (Wf) = Ges * P / 4 * II * Rf**2 (2) 13.997 Watts/meters**2 1.400 mWatts/om**2 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: (3) Extent of the Near Field, (Rn) D+*2 / (4 * lambda) (3) = 252.1 meters The maximum power density in the Near Field can be determined from the following equation: (4) Near Field Power Density, (Wn) 16.0 * n * P / II + D++2 (4) 1 32.675 Watts/meters**2 3.268 mWatts/om**2 1

ATTACHMENT B Page 3 of 5 3. Transition Region Calculations 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: (5) Transition region Power Density, (Tt) Wn * Rn / Rt (5) 3.268 mWatts/om**2 4. Region between Main Reflector and Subreflector Transmissions from the feed assembly are directed toward the subreflector surface, and are reflected back toward the main reflector. The most common feed assemblies are waveguide flanges, horns or subreflectors. The energy between the subreflector and the reflector surfaces can be calculated by determining the power density at the subreflector surface. This can be determined from the following equation: (6) Power Density at Feed Flange, (Ws) = 4 * P / As (6) = 707.355 mWatts/om**2 5. Main Reflector Region The power density in the main reflector is determined in the same manner as the power density at the subreflector. The area is now the area of the main reflector aperture and can be determined from the following equation: (7) Power Density at the Main Reflector Surface, (Wm) = 4 * P / Sa (7) = 51.969 Watts/meters**2 = 5.197 mWatts/om**2 6. Region between Main Reflector and Ground Assuming uniform illumination of the reflector surface, the power density between the antenna and ground can be determined from the following equation: (8) Power Density between Reflector and Ground, (Wg) P / Sa (8) 1 12.992 Watts/meters**2 1.299 mWatts/om**2 n

ATTACHMENT B Page 4 of 5 Table 4. Summary of Expected Radiation levels for Uncontrolled Environment Calculated Maximum Radiation Power Density Level Region (mWatts/om**2) Hazard Assessment 1. Far Field (Rf) = 605.1 meters 1.400 Potential Hazard 2. Near Field (Rn) = 252.1 meters 3.268 Potential Hazard 3. Transition Region Rn < RE < Rf, (Rt) 3.268 Potential Hazard 4. Between Main Reflector 707 .355 Potential Hazard and Subreflector 5. Main Reflector $.197 Potential Hazard 6. Between Main Reflector 1.299 Potential Hazard and Ground Table 5. Summary of Expected Radiation levels for Controlled Environment Calculated Maximum Radiation Power Density Level Region (mWatts/om**2) Hazard Assessment 1. Far Field (Rf) = 605.1 meters 1.400 Satisfies FCC MPE 2. Near Field (Rn) = 252.1 meters 3.268 Satisfies FCC MPE 3. Transition Region Rn < RE < Rf, (Rt) 3.268 Satisfies PCC MPE 4. Between Main Reflector 707 .355 Potential Hazard and Subreflector 5. Main Reflector $.197 Potential Hazard 6. Between Main Reflector 1.299 Satisfies FCC MPE and Ground It is the applicant‘s responsibility to ensure that the public and operational personnel are not exposed to harmful levels of radiation.

ATTACHMENT B Page 5 of 5 Conclusions Based on this analysis it is concluded that the FCC RF Guidelines have been exceeded in the specific regions of Tables 1 and 2. The applicant proposes to comply with the Maximum Permissible Exposure (MPE) limits of 1 mW/cm2 for the Uncontrolled areas and the MPE limits of 5 mW/cm2 for the Controlled areas by one or more of the following methods: Means of Compliance Uncontrolled Areas This antenna will be located in a fenced area. The area will be sufficient to prohibit access to the areas that exceed the MPE limited. The general public will not have access to areas within % diameter removed from the edge of the antenna. Since one diameter removed from the main beam of the antenna or % diameter removed from the edge of the antenna the RF levels are reduced by a factor of 100 or 20 dB. None of the areas exceeding the MPE levels will be accessible by the general public. Radiation hazard signs will be posted while this earth station is in operation. The applicant will ensure that no buildings or other obstacles will be in the areas that exceed the MPE levels. Means of Compliance Controlled Areas The earth station‘s operational will not have access to the areas that exceed the MPE levels while the earth station is in operation. The transmitters will be turned off during antenna maintenance.

ATTACHMENT B Page 1 of 5 Analysis of Non—Tonizing Radiation for a 10.0 Meter Earth Station System This report analyzes the non—ionizing radiation levels for a 10.0 meter earth station system. The analysis and calculations performed in this report are in compliance 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 ReO 96—326. Bulletin No. 65 and the rCC R&O specifies that there are two separate tiers of exposure limits that are dependant 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 described 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 subreflector or feed and main reflector surface, at the main reflector surface, and between the antenna edge and the ground and to compare these levels to the specified MPEs. Table 1. Limits for General Population/Uncontrolled Exposure (MPE) Frequency Range (MHz) Power Density (mWatts/cm**2) 30—300 0.2 300—1500 Frequency (MHz) * (0 . 8/1200) 1500—100, 000 1.0 Table 2. Limits for Occupational/Controlled Exposure (MPE) Frequency Range (MHz) Power Density (mWatts/om**2) 30—300 1.0 300—1500 Frequency (MHz) * (4 . 0/1200) 1500—100, 000 c $.0 Table 3 contains the parameters that are used to calculate the various power densities for the earth stations.

ATTACHMENT B Page 2 of 5 Table 3. Formulas and Parameters Used for Determining Power Flux Densities Parameter Abbreviation Value Units Antenna Diameter D 10.0 meters Antenna Surface Area Sa II * D+*2/4 meters**2 Subreflector Diameter Ds 94.4 cm Area of Subreflector As II * Ds**2/4 cme*2 Frequency Frequency 6175 MHz Wavelength lambda 300 /frequency (MHz) meters Transmit Power P 500. 00 Watts Antenna Gain Ges 54 .0 asi pi II 3.1415927 n/a Antenna Efficiency n 0.60 n/a 1. Far Field Distance Calculation The distance to the beginning of the far field can be determined from the following equation: (1) Distance to the Far Field Region, (Rf) = 0.60 * D+**2 / lambda (2) 1235.0 meters The maximum main beam power density in the Far Field can be determined from the following equation: (2) On—Axis Power Density in the Far Field, (Wf) = Ges * P / 4 * II * Rf**2 (2) 6.553 Watts/meters**2 0.655 mWatts/om**2 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: (3) Extent of the Near Field, (Rn) D+*2 / (4 * lambda) (3) 1 514.6 meters The maximum power density in the Near Field can be determined from the following equation: (4) Near Field Power Density, (Wn) 16.0 * n * P / II * D+*2 (4) 1 15.297 Watts/meters**2 1.530 mWatts/on**2 n

ATTACHMENT B Page 3 of 5 3. Transition Region Calculations 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:(5) Transition region Power Density, (Tt) Wn * Rn / Rt (5) = 1.530 mWatts/om**2 4. Region between Main Reflector and Subreflector Transmissions from the feed assembly are directed toward the subreflector surface, and are reflected back toward the main reflector. The most common feed assemblies are waveguide flanges, horns or subreflectors. The energy between the subreflector and the reflector surfaces can be calculated by determining the power density at the subreflector surface. This can be determined from the following equation: (6) Power Density at Feed Flange, (Ws) 4 * P / As (6) n 285.757 wWatts/om**2 5. Main Reflector Region The power density in the main reflector is determined in the same manner as the power density at the subreflector. The area is now the area of the main reflector aperture and can be determined from the following equation: (7) Power Density at the Main Reflector Surface, (Wm) = 4 * P / Sa (7) = 25.465 Watts/meters**2 = 2.546 mWatts/om**2 6. Region between Main Reflector and Ground Assuming uniform illumination of the reflector surface, the power density between the antenna and ground can be determined from the following equation: (8) Power Density between Reflector and Ground, (Wg) P / Sa (8) n in 6.366 Watts/meters**2 0.637 mWatts/cm**2

ATTACHMENT B Page 4 of 5 Table 4. Summary of Expected Radiation levels for Uncontrolled Environment Calculated Maximum Radiation Power Density Level Region (mWatts/om**2) Hazard Assessment 1. Far Field (Rf) = 1235.0 meters 0.655 Satisfies FCC MPE 2. Near Field (Rn) = 514.6 meters 1.530 Potential Hazard 3. Transition Region Rn < Rt < Rf, (RE) 1.530 Potential Hazard 4. Between Main Reflector 285 .757 Potential Hazard and Subreflector 5. Main Reflector 2.546 Potential Hazard 6. Between Main Reflector 0.637 Satisfies FCC MPE and Ground Table 5. Summary of Expected Radiation levels for Controlled Environment Calculated Maximum Radiation Power Density Level Region (mWatts/om**2) Hazard Assessment 1. Far Field (Rf) =1235.0 meters 0.655 Satisfies FCC MPE 2. Near Field (Rn) = 514.6 meters 1.530 Satisfies FCC MPE 3. Transition Region Rn < Rt < Rf, (Rt) 1.530 Satisfies FCC MPR 4. Between Main Reflector 285 .757 Potential Hazard and Subreflector 5. Main Reflector 2.546 Satisfies FCC MPE 6. Between Main Reflector 0.637 Satisfies FCC MPR and Ground It is the applicant‘s responsibility to ensure that the public and operational personnel are not exposed to harmful levels of radiation.

ATTACHMENT B Page 5 of 5 7. Conclusions Based on this analysis it is concluded that the FCC RF Guidelines have been exceeded in the specific regions of Tables 1 and 2. The applicant proposes to comply with the Maximum Permissible Exposure (MPE) limits of 1 mW/cm2 for the Uncontrolled areas and the MPE limits of 5 mW/cm2 for the Controlled areas by one or more of the following methods: Means of Compliance Uncontrolled Areas This antenna will be located in a fenced area. The area will be sufficient to prohibit access to the areas that exceed the MPE limited. The general public will not have access to areas within % diameter removed from the edge of the antenna. Since one diameter removed from the main beam of the antenna or % diameter removed from the edge of the antenna the RF levels are reduced by a factor of 100 or 20 dB. None of the areas exceeding the MPE levels will be accessible by the general public. Radiation hazard signs will be posted while this earth station is in operation. The applicant will ensure that no buildings or other obstacles will be in the areas that exceed the MPE levels. Means of Compliance Controlled Areas The earth station‘s operational will not have access to the areas that exceed the MPE levels while the earth station is in operation. The transmitters will be turned off during antenna maintenance.


Document Created: 2003-09-30 10:41:39
Document Modified: 2003-09-30 10:41:39
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