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This document pretains to SES-MOD-20140319-00149 for Modification on a Satellite Earth Station filing.

IBFS_SESMOD2014031900149_1039695

Radiation Hazard Analysis SR2000 and SR3000 This analysis predicts the radiation levels around a proposed earth station complex, comprised of a single panel type antenna. This report is developed in accordance with the prediction methods contained in OET Bulletin No. 65, Evaluating Compliance with FCC Guidelines for Human Exposure to Radio Frequency Electromagnetic Fields, Edition 97-01, pp 26-30. The maximum level of non-ionizing radiation to which employees may be exposed is limited to a power density level of 5 milliwatts per square centimeter (5 mW/cm2) averaged over any 6 minute period in a controlled environment and the maximum level of non-ionizing radiation to which the general public is exposed is limited to a power density level of 1 milliwatt per square centimeter (1 mW/cm2) averaged over any 30 minute period in a uncontrolled environment. Note that the worse-case radiation hazards exist along the beam axis. Under normal circumstances, it is highly unlikely that the antenna axis will be aligned with any occupied area since that would represent a blockage to the desired signals, thus rendering the link unusable. Earth Station Technical Parameter Table Antenna Aperture Size 0.59 m x 0.08m Antenna Effective Diameter 0.245 meters Antenna Surface Area 0.047 sq. meters Antenna Isotropic Gain 27.5 dBi Number of Identical Adjacent Antennas 1 Nominal Antenna Efficiency (ε) 42% Nominal Frequency 14.25 GHz Nominal Wavelength (λ) 0.0211 meters Maximum Transmit Power / Carrier 40.0 Watts Number of Carriers 1 Total Transmit Power 40.0 Watts W/G Loss from Transmitter to Feed 1.5 dB Total Feed Input Power 28.32 Watts Radome Losses 0.5 dB Effective RF Power at radome 25.24 Watts Near Field Limit Rnf = D²/4λ = 0.714 meters Far Field Limit Rff = 0.6 D²/λ = 1.71 meters Transition Region Rnf to Rff = 0.714 meters to 1.71 meters In the following sections, the power density in the above regions, as well as other critically important areas will be calculated and evaluated. The calculations are done in the order discussed in OET Bulletin 65. 1.0 At the Antenna Surface The power density at the reflector surface can be calculated from the expression: PDas = 4P/A = 240.29 mW/cm² (1) Where: P = total power at feed, milliwatts A = Total area of reflector, sq. cm 1

In the normal range of transmit powers for satellite antennas, the power densities at or around the reflector surface is expected to exceed safe levels. This area will not be accessible to the general public. This antenna will incorporate a radome which has 0.5 dB of loss. The worst case power density at the surface of the radome is shown below: PDradome=4Prad/A = 214.16 mW/cm² (2) Where: Prad = total power at feed less radome losses, milliwatts A = Total area of reflector, sq. cm (this would represent worst case) Operators and technicians should receive training specifying this area as a high exposure area. Procedures must be established that will assure that all transmitters are rerouted or turned off before access by maintenance personnel to this area is possible. 2.0 On-Axis Near Field Region The geometrical limits of the radiated power in the near field approximate a cylindrical volume with a diameter equal to that of the antenna. In the near field, the power density is neither uniform nor does its value vary uniformly with distance from the antenna. For the purpose of considering radiation hazard it is assumed that the on-axis flux density is at its maximum value throughout the length of this region. The length of this region, i.e., the distance from the antenna to the end of the near field, is computed as Rnf above. The maximum power density in the near field is given by: PDnf = (16ε P)/(π D²) = 90.10 mW/cm² (3) from 0 to 0.713 meters Evaluation Uncontrolled Environment: Does Not Meet Controlled Limits Controlled Environment: Does Not Meet Uncontrolled Limits 3.0 On-Axis Transition Region The transition region is located between the near and far field regions. As stated in Bulletin 65, the power density begins to vary inversely with distance in the transition region. The maximum power density in the transition region will not exceed that calculated for the near field region, and the transition region begins at that value. The maximum value for a given distance within the transition region may be computed for the point of interest according to: PDtr = (PDnf)(Rnf)/R = dependent on R (4) where: PDnf = near field power density Rnf = near field distance R = distance to point of interest PDtr = 90.10 mW/cm² For: 0.713 < R < 1.71 meters We use Eq (4) to determine the safe on-axis distances required for the two occupancy conditions: 2

Evaluation Uncontrolled Environment Safe Operating Distance, (meters), Rsafeu: 64.2 Controlled Environment Safe Operating Distance, (meters), Rsafec: 12.8 4.0 On-Axis Far-Field Region The on- axis power density in the far field region (PDff) varies inversely with the square of the distance as follows: PDff = PG/(4πR²) = dependent on R (5) where: P = total power at feed G = Numeric Antenna gain in the direction of interest relative to isotropic radiator R = distance to the point of interest For: R > Rff = 1.71 meters PDff = 38.60 mW/cm² at Rff We use Eq (5) to determine the safe on-axis distances required for the two occupancy conditions: Evaluation Uncontrolled Environment Safe Operating Distance,(meters), Rsafeu : See Section 3 Controlled Environment Safe Operating Distance,(meters), Rsafec : See Section 3 5.0 Off-Axis Levels at the Far Field Limit and Beyond In the far field region, the power is distributed in a pattern of maxima and minima (sidelobes) as a function of the off-axis angle between the antenna center line and the point of interest. Off-axis power density in the far field can be estimated using the antenna radiation patterns prescribed for the antenna in use. Usually this will correspond to the antenna gain pattern envelope defined by the FCC or the ITU, which takes the form of: Goff = 32 - 25log(Θ) for Θ from 1 to 48 degrees; -10 dBi from 48 to 180 degrees (Applicable for commonly used satellite transmit antennas) Considering that satellite antenna beams are aimed skyward, power density in the far field will usually not be a problem except at low look angles. In these cases, the off axis gain reduction may be used to further reduce the power density levels. For example: At two (2) degrees off axis At the far-field limit, we can calculate the power density as: Goff = 32 - 25log(2) = 32 – 7.52 dBi = 280.2 numeric PD2 deg off-axis = PDffx 280.2/G = 19.23 mW/cm2 (6) 3

6.0 Off-Axis power density in the Near Field and Transitional Regions According to Bulletin 65, off-axis calculations in the near field may be performed as follows: assuming that the point of interest is at least one antenna diameter removed from the center of the main beam, the power density at that point is at least a factor of 100 (20 dB) less than the value calculated for the equivalent on-axis power density in the main beam. Therefore, for regions at least D meters away from the center line of the dish, whether behind, below, or in front under of the antenna's main beam, the power density exposure is at least 20 dB below the main beam level as follows: PDnf(off-axis) = PDnf /100 =0.901 mW/cm² at D off axis (7) See Section 7 for the calculation of the distance vs. elevation angle required to achieve this rule for a given object height. 7.0 Evaluation of Safe Occupancy Area in Front of Antenna The distance (S) from a vertical axis passing through the dish center to a safe off axis location in front of the antenna can be determined based on the dish diameter rule (Item 6.0). Assuming a flat terrain in front of the antenna, the relationship is: S = (D/ sin α) + (2h - D - 2)/(2 tan α) (8) Where: α = minimum elevation angle of antenna D = dish diameter in meters h = maximum height of object to be cleared, meters For distances equal or greater than determined by equation (8), the radiation hazard will be below safe levels for all but the most powerful stations (> 4 kilowatts RF at the feed). For α= 20 degrees, minimum elevation angle of antenna h= 2.0 meters, delta between antenna and object >1 m Then: α S 10 0.7 meters 15 0.5 meters 20 0.4 meters 25 0.3 meters 30 0.3 meters 4

8.0 Summary of Results The earth station site will be protected from uncontrolled access by virtue of the fact that it will be mounted on the roof of a vehicle. There will also be proper emission warning signs placed and all operating personnel will be aware of the human exposure levels at and around the earth station. The applicant agrees to abide by the conditions specified in Condition 18 provided below: (18) - The Raysat Antenna Systems LLC shall take all reasonable and customary measures to ensure that the MET does not create potential for harmful non- ionizing radiation to persons who may be in the vicinty of the MET when it is in operation. At a minimum, permanent warning label(s) shall be affixed to the MET warning of the radiation hazard and including a diagram showing the regions around the MET where the radiation levels could exceed 1.0mW/cm2. The operator of the MET shall be responsible for assuring that individuals do not stray into the region around the MET where there is a potential for exceeding the maximum permissible exposure limits required by Section 1.1310 of the Commission’s rules 47 C.F.R § 1.1310. This shall be accomplished by means of signs, caution tape, verbal warnings, placement of the MET so as to minimize access to the hazardous region and/or any other appropriate means The table below summarizes all of the above calculations. 5

Parameter Abbr. Units Formula Antenna Effective Diameter Df 0.245 meters Antenna Centerline h 2 meters 2 2 Antenna Surface Area Sa 0.047 meter (π*Df )/4 Antenna Ground Elevation GE 2 meters Frequency of Operation f 14.25 GHz Wavelength λ 0.0211 meters HPA Output Power PHPA 40 watts HPA to Antenna Loss LTx 1.5 dB Radome Loss LRad 0.5 dB -1 Transmit Power at Flange P 28.32 watts P/10Log (LTx/10) -1 Effective Power after Radome 25.24 watts P/10Log (Radome Loss/10) Antenna Gain Ges 27.5 dBi does not include radome loss Antenna Aperature Efficiency η 42% n/a 1. Reflector Surface Region Calculations 2 2 Antenna Surface Power Density Pdas 2402.9 W/m (16 * P)/(π * D ) 2 240.29 mW/cm 2 2 Power at Radome Surface Pdrad 2141.6 W/m (16 * P)/(π * D ) 2 (outside radome) 214.16 mW/cm Does not meet controlled limits Does not meet uncontrolled limits 2. On Axis Near Field Calculations 2 Extent of Near Field Rn 0.713 meters D / (4 * λ) 2.338 feet 2 2 Near Field Power Density PDnf 901.0 w/m (16 * η *P)/(π * D ) 2 90.10 mW/cm Does not meet controlled limits Does not meet uncontrolled limits 3. On Axis Transition Region Calculations 2 Extent of Transition Region (min) RTr 0.713 meters D / (4 * λ) Extent of Transition Region (min) 2.338 feet 2 Extent of Transition Region (max) RTr 1.711 meters 0.6 * D / λ Extent of Transition Region (max) 5.612 feet 2 Worst Case Transition Region Power Density PDtr 901.0 w/m 2 90.10 mW/cm Does not meet controlled limits Does not meet uncontrolled limits Uncontrolled enviorment safe operating distance Rsu 64.2 meters (PDnf)/Rnf)/Rsu Controlled enviorment safe operating distance Rsc 12.8 meters (PDnf)/Rnf)/Rsc 4. On Axis Far Field Calculations 2 Distance to Far Field Region Rf 1.71 meters 0.6 * D / λ 5.61 feet 2 2 On Axis Power Density in the Far Field PDff 386.0 W/m (Ges * P) / (4 * π * Rf ) 2 38.60 mW/cm Does not meet controlled limits Does not meet uncontrolled limits 5. Off-axis Power Density in the Far Field Limit and Beyond 2 2 Antenna Surface Power Density PDs 192.3 W/m (Ges * P) / (4 * π * Rf ) * (Goa/Ges) Goa/Ges at a sample angle of θ=2 degrees 0.498 Goa = 32 - 25*log(θ) 2 19.23 mW/cm 6. Off Axis Power Density in the Near Field and Transitional Region Calculations 2 2 Power Density of Wn/100 for 1 diameter PDs 9.01 W/m [(16 * η *P)/(π * D )] / 100 2 removed 0.901 mW/cm Meets controlled limits Meets Uncontrolled limits 7.0 Off-axis Safe Distances from Earth Station minimum elevation angle of antenna α 10 degree hieght of object to be cleared h 2 meter Groun elevation delta antenna-obstacle elevation ang GD S 10 0.7 meter S=(D/sinα) + (2h - D- 2) / (2tanα) 15 0.5 meter 20 0.4 meter 25 0.3 meter 30 0.3 meter Note: Maximum FCC power density limits for 6GHz is 1mW/cm2 for general population exposure as per FCC OS&T 6

StealthRay™ 2000 Te c h S p e c 2-way low-profile in-motion satellite antenna compatible with any external standard Ku band BUC (up to 50W) Physical Outdoor unit size 115 L x 90 W x 15 H cm (45 x 35 x 6 in) Outdoor unit weight 28 kg (62 lb) Indoor unit size 18 L x 23 W x 7 H cm (7 x 9 x 3 in) Indoor unit weight 1.3 kg (2.8 lb) (The radome is included in all measurements and dimensions) Electrical Frequency band Receive High band 11.7 - 12.75 GHz Low band 10.95 - 11.7 GHz (Factory option) Transmit 14.0 - 14.5 GHz Polarization Linear (auto polarization control) Gain Receive 30 dBi Transmit 27 dBi Antenna G/T 8 dB/°K at 30° elevation or 9 dB/°K at 45° elevation Uplink EIRP 41.7 dBW (with external 40 Watt BUC) Specifications subject to change without notice Cross polarization > 25dB IF input (Tx) 950 - 1450 MHz IF output (Rx) 950 - 2150 MHz Ku band input 14 - 14.5 GHz, 50W max. Power supply 10 - 30 VDC Continuous power consumption 55 W (ant. only, excluding BUC) Antenna Performance Elevation look angle range Automatically adjusted, 25° - 80° Azimuth angle range Automatically adjusted, 360° continuous Tracking rate 60°/sec Polarization angle range Automatically adjusted, -180º to +180º Initial satellite acquisition & lock < 60 sec, fully automated with integrated GPS Satellite re-acquisition < 10 sec (when LoS blocage is < 2 minutes) Azimuth tracking accuracy 0.5°@ 60°/s, 360°/s2 Elevation tracking accuracy 1.0°@ 45°/s, 180°/s2 Electrical Interfaces Tx input N (50Ω) Rx output TNC (50Ω) Environmental Temperature range -25º to +70ºC (-13º to +158ºF) Relative humidity Up to 95% Ground speed Up to 350 Km/h (220 mi/h) About RAS Established in 2006, Raysat Antenna Systems (RAS) is a world leader in providing low-profile,in-motion, two-way satellite antennas for land mobile applications of COTM (Comms on-the-move). RAS products are used extensively for mobile emergency communications, homeland security, governmental organizations, DSNG, private security, asset tracking, research & exploration, and general mobile satellite data communications. RAS products operate in both Ku and Ka bands. RAS is a wholly owned subsidiary of Gilat Satellite Networks (NASDAQ: GILT). RAS, LTD. 21 Yegia Kapayim Street, Kiryat Arye, Petach Tikva, Israel 49130 T: +972-3-9707800; F: +972-3-9707801 To Contact RAS International Sales & Marketing Team email sales-RAS@raysat.com l www.raysat.com


Document Created: 2014-03-19 13:56:36
Document Modified: 2014-03-19 13:56:36
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