Attachment to April 26 Response

0970-EX-CN-2018 Text Documents

WorldVu Satellites Limited

2019-04-26ELS_228598

APPENDIX A RADIATION HAZARD REPORT: INTELLIAN 12 dB/K DUAL PARABOLIC ANTENNA In accordance with OET Bulletin 65, this Radiation Hazard Report measured radiation exposure levels in seven zones for two cases—general population and occupational—at the closest point to the uncontrolled area of any testing location and measured at the lowest elevation angle of any testing location. The radiation levels calculated for each zone in Section II are derived from the calculations made in Section I. The results in Section III for OneWeb’s 12 dB/K Dual Parabolic antenna illustrate any radiation hazard that may exist for the general public and/or occupationally will be mitigated by a protective layer covering the antenna. I. Defined Variables for OET Bulletin 65 Calculated Variables OET 65 Calculated Variables Value Unit Formula Value Unit Variables D= λ= Aperture 0.75 Meters c/F 0.0210 Meters Wavelength Diameter d= PI = Subreflector 0.085 Meters Total Antenna Input P*p 1.15 Watts Diameter Power η= A= Aperture 70% Percentage π(D/2)2 0.44179 Meters2 Area of reflector Efficiency a= FCC Designation Ku Band area of π(d/2)2 0.00567 Meters2 sub-reflector F= G= G= 14250 MHz 8780.28545 Linear Frequency Antenna Gain 4πηA/λ2 P= Transmitter 1.15 Watts Antenna Gain dB 10log 10 (G) 39.44 dBi Power Watts p= R nf = Number of 1 # R nf = D2/4λ 6.68 Meters Near-Field Region Transmitters R ua = Closest Point to 0.38 Meters 6.68 >Meters Uncontrolled Area Transition Region >R nf <R ff R ua = Elevation angle 30 Degrees 16.04 <Meters at closest point 16.04 Meters R ff = R ff = Meters Far-Field Region 0.6D2/λ 9.2 AGL 1

II. Radiation Levels in Each Zone Exposure Limits Met General Radiation Analysis Zone Formula Level Value Occupational Public <1mW/cm2 <5mW/cm2 1 Power Sub-reflector 4P I/a 81.064 mW/cm2 No No 2 Antenna Surface 4P I/A 1.041 mW/cm2 No Yes 3 Main Reflector Ground P I/A 0.260 mW/cm2 Yes Yes S nf = 4 Near-Field 4η(P I/A) 0.729 mW/cm2 Yes Yes Power Density Transition 5 S nf *R nf /R nf 0.729 mW/cm2 Yes Yes Max Power Density Far-Field 6 P I*G/4πR2 0.312 mW/cm2 Yes Yes Max Power Density 7 Off-axis Near Field Snf-20dB 0.00729 mW/cm2 Yes Yes III. Results OneWeb’s 12 dB/K Dual Parabolic antenna creates no general population nor occupational radiation hazard. Zones 3 through 7 create no radiation hazard concerns because the radiation levels are below the acceptable exposure limits. Although Zone 1—Power Sub-reflector—exceeds the acceptable general population and occupational radiation exposure limits and Zone 2—Antenna Surface—exceeds the acceptable general population radiation exposure limits, there is no radiation hazard concern because these zones are contained within a protective radome. Accordingly, there is no risk of radiation exposure beyond the acceptable limits. 2

APPENDIX B RADIATION HAZARD REPORT: 15 dB/K DUAL PARABOLIC ANTENNA In accordance with OET Bulletin 65, this Radiation Hazard Report measured radiation exposure levels in seven zones for two cases—general population and occupational—at the closest point to the uncontrolled area of any testing location and measured at the lowest elevation angle of any testing location. The radiation levels calculated for each zone in Section II are derived from the calculations made in Section I. The results in Section III for OneWeb’s 15 dB/K Dual Parabolic antenna illustrate any radiation hazard that may exist for the general public and/or occupationally will be mitigated by a protective layer covering the antenna. I. Defined Variables for OET Bulletin 65 Calculated Variables OET 65 Calculated Variables Value Unit Formula Value Unit Variables D= λ= Aperture 1.0 Meters c/F 0.0210 Meters Wavelength Diameter d= PI = Subreflector 0.085 Meters Total Antenna Input P*p 0.58 Watts Diameter Power η= A= Aperture 70% Percentage π(D/2)2 0.78540 Meters2 Area of reflector Efficiency a= FCC Designation Ku Band area of π(d/2)2 0.00567 Meters2 sub-reflector F= G= G= 14250 MHz 15609.3963 Linear Frequency Antenna Gain 4πηA/λ2 P= Transmitter 0.58 Watts Antenna Gain dB 10log 10 (G) 41.93 dBi Power Watts p= R nf = Number of 1 # R nf = D2/4λ 11.88 Meters Near-Field Region Transmitters R ua = Closest Point to 0.52 Meters 11.88 >Meters Uncontrolled Area Transition Region >R nf <R ff R ua = Elevation angle 30 Degrees 28.52 <Meters at closest point 28.52 Meters R ff = R ff = Meters Far-Field Region 0.6D2/λ 16.5 AGL 3

II. Radiation Levels in Each Zone Exposure Limits Met General Radiation Analysis Zone Formula Level Value Occupational Public <1mW/cm2 <5mW/cm2 1 Power Sub-reflector 4P I/a 40.885 mW/cm2 No No 2 Antenna Surface 4P I/A 0.295 mW/cm2 Yes Yes 3 Main Reflector Ground P I/A 0.074 mW/cm2 Yes Yes S nf = 4 Near-Field 4η(P I/A) 0.207 mW/cm2 Yes Yes Power Density Transition 5 S nf *R nf /R nf 0.207 mW/cm2 Yes Yes Max Power Density Far-Field 6 P I*G/4πR2 0.089 mW/cm2 Yes Yes Max Power Density 7 Off-axis Near Field Snf-20dB 0.00207 mW/cm2 Yes Yes III. Results OneWeb’s 15 dB/K Dual Parabolic antenna creates no general population nor occupational radiation hazard. Zones 2 through 7 create no radiation hazard concerns because the radiation levels are below the acceptable exposure limits. Although Zone 1—Power Sub-reflector—exceeds the acceptable general population and occupational radiation exposure limits, there is no radiation hazard concern because this zone is contained within a protective radome. Accordingly, there is no risk of radiation exposure beyond the acceptable limits. 4

APPENDIX C The Ku-band EPFDup results from the EPFD validation computer program using the input data explained above are shown below. The labeling of the diagram indicates the frequency (in GHz), the reference bandwidth (40 kHz), the beamwidth of the reference GSO satellite receiving antenna beam (4.0 degrees) and the fact that this is a FSS EPFD limit. 1 Also stated is the worst- case geometry defined by the latitude of the pointing direction of the reference GSO satellite receiving beam and the Δlong (difference in longitude between this pointing direction and the corresponding GSO satellite). This worst-case geometry has been determined by the EPFD validation software to be the worst case (i.e., highest EPFD levels) according to the Recommendation ITU-R S.1503-2. The resulting EPFD level is shown by the blue curve and the EPFD mask is shown by the red line. Worst-case geometry: GSO satellite pointing direction latitude = 42.552°N, Δlong = 0.0° The results above demonstrate that the OneWeb system complies with the Commission’s and the ITU’s EPFDdown and EPFDup limits. 1 The frequency used for the analysis is determined by the EPFD validation software and is the lower end of the range of frequencies for the particular GSO allocation. For example, the frequency is 14.0 GHz for the FSS frequency range of 14.0-14.5 GHz. 5


Document Created: 2019-04-26 17:52:44
Document Modified: 2019-04-26 17:52:44
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