Attachment RF Hazard Study

This document pretains to SES-AMD-20120210-00165 for Amended Filing on a Satellite Earth Station filing.

IBFS_SESAMD2012021000165_938250

MPE Analysis For Earth Station TeleBEEPER of New Mexico, Inc. Site Location 4545 McLeod, Albuquerque, NM 87109 Latitude: 35 °08 ’15.9 "N Longitude: 106 °35 ’40.4 "W February 3, 2012

Analysis of Non-Ionizing Radiation for TeleBEEPER 1.8m Earth Station System This report analyzes the non-ionizing radiation levels for a 1.8-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 01-01. 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 30 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 sub-reflector 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 MPE's. Table 1 - FCC Limits for Maximum Permissible Exposure (MPE) Limits for Occupational (Controlled) Exposure Electric Power Averaging Frequency Magnetic Field Field Density Time Band Strength Range Strength (H) (S) |E|, |H| or S (E) (MHz) (V/m) (A/m) (mW/cm2) (minutes) 1 0.3-3.0 614 1.63 (100)* 6 2 3.0-30 1842/f 4.89/f (900/f2)* 6 3 30-300 61.4 0.163 1 6 4 300-1500 -- -- f/300 6 1500- 5 -- -- 5 6 100,000 f = frequency in MHz *Plane-wave equivalent power density T eleBEEPER of New Mexico, Inc Page |1

MPE Analysis February 3, 2012 Table 2 - FCC Limits for Maximum Permissible Exposure (MPE) Limits for General Population (Uncontrolled) Exposure Electric Magnetic Power Frequency Averaging Time Field Field Density Band Range Strength (E) Strength (H) (S) |E|, |H| or S (MHz) (V/m) (A/m) (mW/cm2) (minutes) 1 0.3-1.34 614 1.63 (100)* 30 2 1.34-30 824/f 2.19/f (180/f2)* 30 3 30-300 27.5 0.073 0.2 30 4 300-1500 -- -- f/1500 30 1500- 5 -- -- 1 30 100,000 f = frequency in MHz *Plane-wave equivalent power density TeleBEEPER parameters for its earth station is shown in Table 3 below Table 3 - Earth Station Parameters Antenna Diameter D 1.8 meter Sub‐reflector Diameter Ds 15.78 cm Frequency F 14250 MHz Wavelength (300/F) λ 0.021053 m Transmit Power = 6.02 dBw PFeed 4 Watts Antenna Gain G 46.5 dBi Antenna GainNumberic GNumeric 44668.36 Effective Radiated Isotropic Power (108908.05) Watts EiRP 52.52 dBiW Pi Π 3.141593 n/a Antenna Efficiency ή 0.7 n/a Table 4 represents the power density calculations based on FCC Bulletin 65 T eleBEEPER of New Mexico, Inc Page |2

MPE Analysis February 3, 2012 Table 4 - Power Density Formulas and Calculation I. Near Field: RNear = extent of the near‐field (m) D = diameter of the antenna main reflector (m) 1.8 m λ = wavelength of the RF transmit frequency (m) 0.021053 m 2 RNear =(D) /4λ Rnear = 38.48 m 2 SNear = maximum on axix power density within near field (mW/cm ) ή = antenna aperture efficiency 0.7 PFeed = maximum power into antenna feed flange (W) 4W D = diameter of the antenna main reflector (m) 1.8 m Π = Pi 3.141593 2 2 SNear ={(16ήPfeed)/[Π(D) ]}/10 Snear = 0.440132 mW/cm II. Far Field RFar = distance to beginning of far field (m) D = diameter of the antenna main reflector (m) λ = wavelength of the RF transmit frequency (m) 2 RFar =[0.6(D) ]/λ RFar= 92.34 m 2 SFar = maimum on‐axis power density in the far field (mW/cm ) PFeed = maximum power into antenna feed flange (W) 4W GNumeric = antenna main beam gain at RF transmit frequency (number) 44668.36 RFar = distance to beginning of far field (m) 92.34 m 2 2 SFar = [(PFeed G numeric)/4Π(RFar) ]/10 SFar = 0.166752 mW/cm III. Antenna Transition Region Power Density Calculation 2 STr = maximum on‐axis power density in transition region (mW/cm ) 2 SNear = maximum on‐axis power density within near field (mW/cm ) RNear = extent of the near‐filed (m) RTra = distance within transition region between near field and far field region RTra = RFar ‐ RRear Rtra = 53.87 2 STr = SNearRNear/R Stra = 0.31438 mW/cm STr < Snear then it is OK IV. Antenna Feed‐Flange (Or Sub reflector) Power Density Calculation 2 SFeed ‐ Sub = max power density at antenna feed flange or sub‐reflector surface (mW/cm ) PFeed = maximum power into antenna feed flange (W) 4W DFeed‐ Sub = diameter of the antenna feed‐flange or sub‐reflector (cm) 15.78 cm 2 2 SFeed‐Sub = 1000{[4(PFeed)]/{[Π(DFeed‐Sub) ]/4}} 81.81183 mW/cm V. Antenna Main Reflector Power Density Calculation 2 SAnt = maximum power density in the antenna main reflector region (mW/cm ) PFeed = maximum power into antenna feed flange (W) 4W D = diameter of the antenna main reflector (m) 1.8 m 2 2 SAnt = {[4(PFeed)]/{[ΠD) /4}}/10 0.62876 mW/cm VI. Power Density Calculation between the Antenna Main Reflector and the Ground 2 SGround = maximum power density between the antenna main reflector and ground (mW/cm ) PFeed = maximum power into antenna feed flange (W) 4W D = diameter of the antenna main reflector (m) 1.8 m 2 2 SGround ={PFeed/{[Π(D) ]/4}}/10 0.15719 mW/cm T eleBEEPER of New Mexico, Inc Page |3

MPE Analysis February 3, 2012 The non-ionize RF radiation summary can be found in Tables 5 and 6 Table 5 - Summary of Expected Radiation levels for Uncontrolled Environment Region Calculated Hazard Assessment Diannce Near Field (RNear) 38.48 m Distance to the Far Field (RFar) 92.34 m 2 Power Density Near Field 0.440132 mW/cm Satisfies FCC MPE 2 Power Density Far Field 0.166752 mW/cm Satisfies FCC MPE Transition Region RNear < RTra < Rfar RNear =38.475 < RTran =53.865 < RFar =92.34 2 Power Density Transition Region 0.314380 mW/cm Satisfies FCC MPE 2 Power Density Antenna Feed Flange 81.811828 mW/cm Potential Hazard 2 Power Density Antenna Main ReflectorReflector Surface 0.628760 mW/cm Satisfies FCC MPE 2 Power Density Between Reflector and the Ground Between Reflector 0.157190 mW/cm Satisfies FCC MPE Table 6 - Summary of Expected Radiation levels for Controlled Environment Region Calculated Hazard Assessment Diannce Near Field (RNear) 38.48 m Distance to the Far Field (RFar) 92.34 m 2 Power Density Near Field 0.440132 mW/cm Satisfies FCC MPE 2 Power Density Far Field 0.166752 mW/cm Satisfies FCC MPE Transition Region RNear < RTra < Rfar RNear =38.475 < RTran =53.865 < RFar =92.34 2 Power Density Transition Region 0.314380 mW/cm Satisfies FCC MPE 2 Power Density Antenna Feed Flange 81.811828 mW/cm Potential Hazard 2 Power Density Antenna Main ReflectorReflector Surface 0.628760 mW/cm Satisfies FCC MPE 2 Power Density Between Reflector and the Ground Between Reflector 0.157190 mW/cm Satisfies FCC MPE The above analysis confirms the presence of potentially hazardous power flux densities at the TeleBEEPER terminal which will require physical and operational protections to manage General Population and Occupational exposure. The TeleBEEPER Antenna at the Albuquerque, NM facility will be located on a roof of an existing building where for RF safety, physical safety, and security purposes access to the antenna is controlled by TeleBEEPER. The size of the access area on the roof will consider the RF hazards, moving antenna 'swept volume', and the surrounding terrain. In addition to fencing, the area will contain signage which clearly states the standard Radiation Hazard warning. TeleBEEPER will ensure antenna tracking geometry maintains angular limits and other occupied areas where the calculated General Population MPE levels may be exceeded. T eleBEEPER of New Mexico, Inc Page |4


Document Created: 2012-02-06 09:00:52
Document Modified: 2012-02-06 09:00:52
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