Attachment Exhibit C - RadHaz

This document pretains to SES-MFS-20150424-00270 for Modification w/ Foreign Satellite (earth station) on a Satellite Earth Station filing.

IBFS_SESMFS2015042400270_1085990

Exhibit C Radiation Hazard Analysis Introduction This exhibit constitutes the Radiation Hazard Analysis for Row 44’s transmitter considering the FCC procedure outlined in FCC Bulletin #65. The limit for exposure to RF energy, (frequencies greater than 1.5 GHz), is 5 mW/cm2 up to a 6 minute duration (categorized as Occupational / ’Controlled Exposure’), and 1 mW/cm2 up to a 30 minute duration (categorized as General Population / ‘Uncontrolled Exposure’).1 Analysis regarding radiation exposure is presented considering behavior in the Near Field, Far Field and Transition ‘regions’. Appropriate separation-distances are provided for the ‘Controlled’ and ‘Uncontrolled Exposure’ scenarios, considering individuals located in the direction of either the antenna’s main beam or its side-lobes. Analysis The extent of the Near Field region in the main beam is defined as distances out to a radius Rnf according to the relation Rnf = D2/4λ where D is the antenna panel width and λ is the transmit wavelength. The Near Field maximum Power Density, Snf, is determined from Snf = 0.1η PPA/A (in mW/cm2) where PPA is the transmit power (after cable losses), A is the surface area of the antenna aperture, and η the efficiency of the antenna aperture. (With an antenna height h, the surface area A = Dh.) The Far Field region for the main beam is defined as beginning and continuing out-from a radius Rff , given by Rff = 0.60 D2/λ 1 “Questions and Answers about Biological Effects and Potential Hazards of Radiofrequency Electromagnetic Fields,” Federal Communications Commission, Office of Engineering and Technology, Bulletin 65, Fourth Edition, August, 1999, p.15. http://www.fcc.gov/Bureaus/Engineering_Technology/Documents/bulletins/oet56/oet56e4.pdf 1

The Far Field Power Density Sff at the Far Field radius and farther is determined (in terms of the EIRP, denoted by PEIRP) from Sff = PEIRP/4π Rff2 (in mW/cm2) (The value of PEIRP should already consider coax losses and aperture efficiency.) Note that when the radius is expressed in meters, the Power Density is in units of W/m2. The results are converted to units consistent with the FCC limits (mW/cm2) by multiplying values in W/m2 by 0.1. Exposure from the Main Antenna Beam Row 44’s antenna has dimensions D = 0.625 m (24.6”), h = 0.157 m (6.2”), and a surface area A = 0.098m2. At the highest transmit frequency of 14.5 GHz, the wavelength is 0.0207 m. The Near Field radius is then Rnf = 4.72 m The antenna aperture efficiency factor is 0.93 and the feeder coax loss is 4.58 dB. Based on the wavelength and panel-width given farther above, the Far Field radius is then Rff = 11.33 m In the operation of Row 44’s system, the antenna may be fed with ten different signal levels, as provided in Tables 1 and 2. The associated Near Field radius Power Density values are: Table 1 Transmit Power and Near Field Power Density at Distance Rnf Transmit power (dBm) EIRP (dBW) Snf (mW/cm2) 45.0 43.8 10.4 44.5 43.3 9.30 43.2 42.0 6.90 43.0 41.8 6.59 42.5 41.3 5.87 42.0 40.8 5.23 41.5 40.3 4.66 40.5 39.3 3.70 40.2 39.0 3.46 40.0 38.8 3.30 39.0 37.8 2.62 37.5 36.3 1.86 37.2 36.0 1.73 34.5 33.3 .930 2

(Note that the equation for the maximum Power Density in the Near Field considers a given radiated signal/ power confined-to and passing-through a physical area corresponding to that of the antenna aperture. Along these lines, the Snf values cannot be assumed to vary with distance from the antenna, for locations within the Near Field.) The associated Far Field radius Power Density values are as well: Table 2 Transmit Power, EIRP and Far Field Power Density at Distance Rff Transmit power (dBm) EIRP (dBW) Sff (mW/cm2) 45.0 43.8 1.49 44.5 43.3 1.33 43.2 42.0 .983 43.0 41.8 .939 42.5 41.3 .837 42.0 40.8 .746 41.5 40.3 .664 40.5 39.3 .528 40.2 39.0 .493 40.0 38.8 .470 39.0 37.8 .374 37.5 36.3 .265 37.2 36.0 .247 34.5 33.3 .133 We are considering exposure to two values of Power Density: 5 mW/cm2 and 1 mW/cm2. 5 mW/cm2 Analysis Some of the Snf values in Table 1 are greater than 5 mW/cm2, and some are less than 5 mW/cm2. As the Near Field analysis assumes that the Power Density in the Near Field does not vary with distance, for cases where Snf exceeds 5 mW/cm2, there is no location in the Near Field where the Power Density is less. An individual therefore cannot be located in the Near Field anywhere whatsoever at all to avoid such an exposure level. We’ll defer this analysis to the ‘Transition Region’ between the Near and Far Fields: Assuming that the Power Density decreases linearly between the Near Field radius and the Far Field radius, the distance at which the Power Density will equal 5 mW/cm2 (for the selected TX powers) is given in Table 3. Table 3 Separation for ‘Controlled Exposure’ Limit (Main Beam) Transmit power (dBm) Separation for ‘Controlled’ Limit (5 mW/cm2) meters feet 45.0 8.74 28.7 44.5 8.29 27.2 3

43.2 6.84 22.4 43.0 6.58 21.6 42.5 5.86 19.2 42.0 5.06 16.6 Somewhat similar to the above, applicable to cases where Snf is less than 5 mW/cm2, in attempting to determine the location at which the Power Density may equal 5 mW/cm2, we cannot project a location closer than Rnf. For such cases in the Near Field, we shall adopt a precautionary stance, and will assign (Table 4) the Near Field radius of 4.72 meters (15.5 feet) as the minimum physical separation to facilitate an exposure no greater than 5 mW/cm2. Table 4 Separation for ‘Controlled Exposure’ Limit (Main Beam) Transmit power (dBm) Separation for ‘Controlled’ Limit (5 mW/cm2) meters feet 41.5 4.72 15.5 40.5 4.72 15.5 40.2 4.72 15.5 40.0 4.72 15.5 39.0 4.72 15.5 37.5 4.72 15.5 37.2 4.72 15.5 34.5 4.72 15.5 1 mW/cm2 Analysis As the Snf values are each greater than 1 mW/cm2, we need consider distances greater than Rnf where the 1 mW/cm2 will be encountered: The EIRP and the resulting Far Field Power Density at distance Rff are once again provided in Table 5 for each transmit power value: Table 5 Transmit Power, EIRP and Far Field Power Density at Distance Rff Transmit power (dBm) EIRP (dBW) Sff (mW/cm2) 45.0 43.8 1.49 44.5 43.3 1.33 43.2 42.0 .983 43.0 41.8 .939 42.5 41.3 .837 42.0 40.8 .746 41.5 40.3 .664 40.5 39.3 .528 4

40.2 39.0 .493 40.0 38.8 .470 39.0 37.8 .374 37.5 36.3 .265 37.2 36.0 .247 34.5 33.3 .133 Some Sff values exceed 1 mW/cm2, and some do not. For the TX levels where Sff is greater than 1 mW/cm2, we’ll use standard ‘inverse- squared’ analysis to identify the necessary separations listed in Table 6: Table 6 Separation for ‘Uncontrolled Exposure’ Limit (Main Beam) Transmit power (dBm) Separation for ‘Uncontrolled’ Separation for ‘Uncontrolled’ Limit of 1 mW/cm2 (m) Limit of 1 mW/cm2 (feet) 45.0 13.8 45.3 44.5 13.0 42.7 For the remaining TX levels, we need interpolate the Power Density values between Rnf and Rff to project the location at which 1 mW/cm2 exists. Assuming that the Power Density decreases linearly between the Near Field radius and the Far Field radius, the distances at which the Power Density equals 1 mW/cm2 are projected according to Table 7. Table 7 Separation for ‘Uncontrolled Exposure’ Limit (Main Beam) Transmit power (dBm) Separation for ‘Uncontrolled’ Limit (1 mW/cm2) meters feet 43.2 11.3 37.1 43.0 11.3 37.1 42.5 11.1 36.5 42.0 11.0 35.9 41.5 10.8 35.4 40.5 10.3 33.9 40.2 10.2 33.5 40 10.1 33.1 39 9.49 31.1 37.5 8.28 27.2 37.2 7.98 26.2 34.5 4.14 13.6 Exposure from Antenna Beam Side-Lobes 5

The previous calculations assumed the individual was located in the ‘sight’ of the main antenna beam. (The main antenna beam is less than 10 degrees-wide in azimuth.) The following analysis provides insight into the exposure when an individual is located to- the-side or behind the antenna. Table 8 provides Power Density values at distances Rnf and Rff when an individual is located in the direction of the highest antenna side-lobe (which corresponds to a 12 dB gain reduction from the main beam). Table 8 TX Power, Sidelobe Attenuation, and Power Density at Rnf and Rff Tx power (dBm) Sidelobe (dB) Snf (mW/cm2) Sff (mW/cm2) 45.0 -12 0.659 0.0939 44.5 -12 0.587 0.0837 43.2 -12 0.435 0.0620 43.0 -12 0.416 0.0592 42.5 -12 0.370 0.0528 42.0 -12 0.330 0.0470 41.5 -12 0.294 0.0419 40.5 -12 0.234 0.0333 40.2 -12 0.218 0.0311 40.0 -12 0.208 0.0297 39.0 -12 0.165 0.0236 37.5 -12 0.117 0.0167 37.2 -12 0.109 0.0156 34.5 -12 0.0587 0.00837 As is obvious, neither the Snf or Sff values (at distances Rnf and Rff) exceed even the ‘Uncontrolled’ Limit of 1 mW/cm2. Therefore, no minimum distance of separation will apply for individuals located in directions outside the antenna’s main beam. Summary This document presents the radiation hazard analysis for Row 44’s transmitter transmitting at EIRP values of 43.8, 43.3, 42.0, 41.8, 41.3, 40.8, 40.3, 39.3, 39.0, 38.8, 37.8, 36.3, 36.0, or 33.3 dBW. Considering the worst-case, individuals positioned in the direction of the main beam of the antenna, and in a ‘Controlled Exposure’ environment should be at least 8.74 meters (28.7 feet) away from the antenna aperture (for a 6 minute duration). Under the same circumstances, individuals in a ‘Uncontrolled Exposure’ environment should be at least 13.8 meters (45.3 feet) away from the antenna aperture (for a 30 minute duration). For individuals located in directions which are outside the antenna’s main beam, no minimum distance of separation is applicable. 6


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Document Modified: 2015-04-16 14:11:55
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