Attachment Technical Appendix

This document pretains to SES-LIC-20180201-00081 for License on a Satellite Earth Station filing.

IBFS_SESLIC2018020100081_1331789

TECHNICAL APPENDIX RBC Signals LLC Fixed Earth Station License Application I. 400 MHz Yagi Earth Station Radiation Hazard Report II. 450 MHz Yagi Earth Station Radiation Hazard Report III. 3 Diamonds Satellites A. Orbital Debris and Deorbit Report B. TT&C Link Budgets C. TT&C Contours Map IV. Technical Certification

I. 400 MHz Yagi Earth Station Radiation Hazard Report This study analyzes the non-ionizing radiation levels for a 400 MHz Yagi tracking earth station. 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. Bulletin No. 65 specifies that there are two separate tiers of exposure limits that are depending on the area of exposure and/or the status of the individuals who are subject to the exposure -- the General Population/Uncontrolled Environment and the Controlled Environment, where the general population cannot access. The maximum level of non-ionizing radiation to which individuals may be exposed is limited to a power density level of 1.33 milliwatts per square centimeter (1.33 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 0.27 milliwatt per square centimeter (0.27 mW/cm2) averaged over any 30 minute period in a uncontrolled environment. In the normal range of transmit powers for satellite antennas, the power densities at or around the antenna surface are expected to exceed safe levels. The purpose of this study is to determine the power flux density levels for the earth station under study as compared with the MPE limits. This comparison is done in each of the following regions: 1. Far-field region 2. Near-field region 3. Transition region 4. The region between the antenna edge and the ground Input Parameters The following input parameters were used in the calculations: Parameters: Value Unit Symbol Antenna Diameter 3.57 m D Antenna Transmit Gain 18 dBi G Transmit Frequency 400 MHz f Power Input to the Antenna 8.93 W P Calculated Parameters: The following values were calculated using the above input parameters and the corresponding formulas: Parameter Value Unit Symbol Formula 2

Antenna Surface Area 2.973 m2 A Gλ2/(4π)/λ Antenna Efficiency 0.95 η Gλ2/( π2D2) Gain Factor 63.1 g 10 G/10 Wavelength 0.75 m λ 300/f Behavior of EM Fields as a Function of Distance The behavior of the characteristics of EM fields varies depending on the distance from the radiating antenna. These characteristics are analyzed in three primary regions: the near-field region, the far-field region and the transition region. Of interest also is the region between the antenna and ground. For yagi antennas with circular cross sections, such as the antenna under study, the near-field, far-field and transition region distances are calculated as follows: Parameter Value Unit Formula Near-Field Distance 4.25 m Rnf = D2/(4λ) Distance to Far-Field 10.2 m Rff = 0.60D2/(λ) Distance of Transition Region 4.25 m Rt = Rnf The distance in the transition region is between the near and far fields. Thus, R nf < Rt < Rff. However, the power density in the transition region will not exceed the power density in the near- field. Therefore, for purposes of the present analysis, the distance of the transition region can equate the distance to the near-field. Power Flux Density Calculations The power flux density is considered to be at a maximum through the entire length of the near- field. This region is contained within a cylindrical volume with a diameter, D, equal to the diameter of the antenna. In the transition region and the far-field, the power density decreases inversely with the square of the distance. The following equations are used to calculate power density in these regions. Parameter Value Unit Symbol Formula Power Density in the Near-Field 1.14 mW/cm2 Snf 16.0 η P/(πD2) Power Density in the Far-Field 0.043 mW/cm2 Sff GP/(4π Rff2) Power Density in the Transition Region 1.14 mW/cm2 St Snf Rnf /(Rt) The power density between the antenna and ground, is calculated as follows: Parameter Value Unit Symbol Formula Power Density b/w Reflector and Ground 0.300 mW/cm2 Sg P/A The below table summarizes the calculated power flux density values for each region. In a controlled environment, the only regions that exceed FCC limitations are shown below. These regions are only accessible by trained technicians who, as a matter of procedure, turn off transmit power before performing any work in these areas. 3

Power Density Value Unit Controlled Environment 2 Far Field Calculation 0.043 mW/cm Satisfies FCC MPE 2 Near Field Calculation 1.14 mW/cm Exceeds Limits 2 Transition Region 1.14 mW/cm Exceeds Limits 2 Region b/w Antenna & Ground 0.300 mW/cm Satisfies FCC MPE In conclusion, the results show that the antenna, in a controlled environment, may exist in the regions noted above and applicant will take the proper mitigation procedures to ensure it meets the guidelines specified in 47 C.F.R. § 1.1310. The antenna will be installed at DS12 Access Road, Prudhoe Bay, Alaska 99734. Access to the antenna requires a 45 ft man-lift, which should safely restrict any public access. The earth station will be marked with the standard radiation hazard warnings, as well as the area in the vicinity of the earth station to inform the general population, who might be working or otherwise present in or near the path of the main beam. The applicant will ensure that the main beam of the antenna will be pointed at least one diameter away from any building, or other obstacles in those areas that exceed the MPE limits. Since one diameter removed from the center of the main beam the levels are down at least 20 dB, or by a factor of 100, public safety will be ensured. Finally, the earth station’s operational personnel will not have access to areas that exceed the MPE limits while the earth station is in operation. The transmitter will be turned off during periods of maintenance so that the MPE standard of 1.33 mW/cm2 will be complied with for those regions in close proximity to the antenna, which could be occupied by operating personnel. 4

II. 450 MHz Yagi Earth Station Radiation Hazard Report This study analyzes the non-ionizing radiation levels for a 450 MHz Yagi tracking earth station. 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. Bulletin No. 65 specifies that there are two separate tiers of exposure limits that are depending on the area of exposure and/or the status of the individuals who are subject to the exposure -- the General Population/Uncontrolled Environment and the Controlled Environment, where the general population cannot access. The maximum level of non-ionizing radiation to which individuals may be exposed is limited to a power density level of 1.5 milliwatts per square centimeter (1.5 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 0.3 milliwatt per square centimeter (0.3 mW/cm2) averaged over any 30 minute period in a uncontrolled environment. In the normal range of transmit powers for satellite antennas, the power densities at or around the antenna surface are expected to exceed safe levels. The purpose of this study is to determine the power flux density levels for the earth station under study as compared with the MPE limits. This comparison is done in each of the following regions: 1. Far-field region 2. Near-field region 3. Transition region 4. The region between the antenna edge and the ground Input Parameters The following input parameters were used in the calculations: Parameters: Value Unit Symbol Antenna Diameter 3.15 m D Antenna Transmit Gain 16.5 dBi G Transmit Frequency 450 MHz f Power Input to the Antenna 60.26 W P Calculated Parameters: The following values were calculated using the above input parameters and the corresponding formulas: 5

Parameter Value Unit Symbol Formula Antenna Surface Area 1.663 m2 A Gλ2/(4π)/λ Antenna Efficiency 0.95 η Gλ2/( π2D2) Gain Factor 44.7 g 10 G/10 Wavelength 0.67 m λ 300/f Behavior of EM Fields as a Function of Distance The behavior of the characteristics of EM fields varies depending on the distance from the radiating antenna. These characteristics are analyzed in three primary regions: the near-field region, the far-field region and the transition region. Of interest also is the region between the antenna and ground. For yagi antennas with circular cross sections, such as the antenna under study, the near-field, far-field and transition region distances are calculated as follows: Parameter Value Unit Formula Near-Field Distance 3.72 m Rnf = D2/(4λ) Distance to Far-Field 8.93 m Rff = 0.60D2/(λ) Distance of Transition Region 3.72 m Rt = Rnf The distance in the transition region is between the near and far fields. Thus, R nf < Rt < Rff. However, the power density in the transition region will not exceed the power density in the near- field. Therefore, for purposes of the present analysis, the distance of the transition region can equate the distance to the near-field. Power Flux Density Calculations The power flux density is considered to be at a maximum through the entire length of the near- field. This region is contained within a cylindrical volume with a diameter, D, equal to the diameter of the antenna. In the transition region and the far-field, the power density decreases inversely with the square of the distance. The following equations are used to calculate power density in these regions. Parameter Value Unit Symbol Formula Power Density in the Near-Field 13.77 mW/cm2 Snf 16.0 η P/(πD2) Power Density in the Far-Field 0.27 mW/cm2 Sff GP/(4π Rff2) Power Density in the Transition Region 13.77 mW/cm2 St Snf Rnf /(Rt) The power density between the antenna and ground, is calculated as follows: Parameter Value Unit Symbol Formula 2 Power Density b/w Reflector and Ground 3.62 mW/cm Sg P/A The below table summarizes the calculated power flux density values for each region. In a controlled environment, the only regions that exceed FCC limitations are shown below. These regions are only accessible by trained technicians who, as a matter of procedure, turn off transmit power before performing any work in these areas. 6

Power Density Value Unit Controlled Environment 2 Far Field Calculation 0.27 mW/cm Satisfies FCC MPE 2 Near Field Calculation 13.77 mW/cm Exceeds Limits 2 Transition Region 13.77 mW/cm Exceeds Limits 2 Region b/w Antenna & Ground 3.62 mW/cm Exceeds Limits In conclusion, the results show that the antenna, in a controlled environment, may exist in the regions noted above and applicant will take the proper mitigation procedures to ensure it meets the guidelines specified in 47 C.F.R. § 1.1310. The antenna will be installed at DS12 Access Road, Prudhoe Bay, Alaska 99734. Access to the antenna requires a 45 ft man-lift, which should safely restrict any public access. It should be noted that all spaces at least 8.5 m away from the antenna satisfy the FCC MPE limits for the general population. The earth station will be marked with the standard radiation hazard warnings, as well as the area in the vicinity of the earth station to inform the general population, who might be working or otherwise present in or near the path of the main beam. The applicant will ensure that the main beam of the antenna will be pointed at least one diameter away from any building, or other obstacles in those areas that exceed the MPE limits. Since one diameter removed from the center of the main beam the levels are down at least 20 dB, or by a factor of 100, public safety will be ensured. Finally, the earth station’s operational personnel will not have access to areas that exceed the MPE limits while the earth station is in operation. The transmitter will be turned off during periods of maintenance so that the MPE standard of 1.5 mW/cm2 will be complied with for those regions in close proximity to the antenna, which could be occupied by operating personnel. 7

III. 3 Diamonds Satellites 8

A. Compliance with Orbital Debris and Deorbit Related Requirements Assessment has been made for the Three Diamond Satellites for compliance with the requirements of §25.114(d)(14): (i) The Three Diamonds satellite deployment planning and operational design was assessed to determine compliance with orbital debris release requirements. The Three Diamonds satellites are deployed from a qualified ISIS Quadpack system. The operational design of the Three Diamonds satellite does not include release of any debris during operations in any mission phase. An assessment of the probability of the space station becoming a source of debris by collisions with small debris or meteoroids was performed using the NASA Debris Assessment Software (DAS), version 2.0.2. The Three Diamonds satellite was found to be compliant with the requirement (NS 8719.14 Requirement 4.5-2, Probability of Damage from Small Objects). Figure 1 below shows the DAS summary output screen. (ii) The Three Diamonds satellite design has been assessed and found that the design limits the probability of accidental explosions during and after completion of mission operations. The only energy sources on board the satellite are the Li-Ion battery and the reaction wheel. Both are planned to be passivated at the end of mission. The Three Diamonds satellites have no propulsion systems, and hence have no residual fuel at end of mission. (iii) The Three Diamonds satellite design has been assessed and found that the probability of the space station becoming a source of debris by collisions with large debris or other operational space stations is compliant with the requirement (NS 8719.14 Requirement 4.5-1, Probability of Collision with Large Objects). Figure 1 below shows the DAS summary output screen. The anticipated evolution over time of the orbit of the Three Diamonds satellites has been assessed with DAS. The predicted orbital lifetime of the satellites is 5.3 years until re-entry into the atmosphere. The DAS orbital evolution is shown in Figure 2 below. (iv) For the Three Diamonds satellites, the post-mission disposal plans at end of life are to rely on the natural orbital evolution, as shown in Figure 2 below, to culminate in atmospheric re- entry. As the satellites have no propulsion system, there is no fuel or other active propulsive means employed during deorbit. For the Three Diamonds Satellites, a casualty risk assessment was performed because the planned post-mission disposal involves atmospheric re-entry. DAS analysis was performed as shows the satellites to be compliant with the requirement (NS 8719.14 Requirement 4.7-1, Casualty Risk from Reentry Debris). Assessment of the Three Diamonds Satellites using DAS has shown the design and operational planning to be compliant with all requirements as shown in Figure 1 below. Note that compliance with Requirement 4.3-2, Mission-Related Debris Passing Near GEO, does not pertain to the Three Diamonds Satellites as they will not approach GEO orbits. Figure 1 also 9

shows compliance with Requirement 4.4-3, Long Term Risk from Planned Breakups, because there are no planned breakups for these satellites. Compliance with Requirement 4.8-1, Collision Hazards with Space Tethers, does not pertain to the Three Diamonds Satellites as they do not employ tethers. Figure 1 - Debris Assessment Software Requirements Compliance Figure 2 – DAS Orbit Evolution 10

UHF Link — Uplink Link parameters Unit Notes Carrier Frequency 399.938 MHz Carrier wavelength 0.75 m Boltzmann constant —228.6 dBwW/K/Hz BASIC PARAMETERS Orbit height 500 km Earth radius 6371 km Horizon height ToR distance 2573 km Ground Segment Antenna Gain 17.0 dBi Dual Crossed Yagis Tx RF power 25.0 W Tx losses 1.6 dB Cable and connector Tx EIRP 29.4 dBw PROPAGATION GS antenna pointing loss 0.5 dB Polarization losses 3.0 dB Worst—case Free space losses 152.7 dB Atmospheric Losses 2.1 dB lonospheric losses 0.4 dB Total Propagation Losses 158.7 dB Satellite Segment Satellite Antenna Pointing Loss 0.0 dB Antenna Gain 0.0 dBi Spacecraft Tx line losses 0.2 dB Antenna Temperature 150 K Earth is half of F.0.V. Satellite Noise Temperature 500 K Estimate System Noise Temperature 650.0 System Noise Temperature 28.1 dBK Rx GIT 28.3 dB/K Final C/No 71.0 dBHz

Receive Channel Bandwidth 7.2 kHz typically 1.5x bit rate Useful bitrate 4.8 kBit GMSK, Conv. R=1/2,K=7 & R.S. Required Eb/No 4.8 dB (255,223) Receiver Implementation Loss 3.0 dB Demodulator phase offset C/No required 46.37 dBHz MARGIN A —> B dB

UHF Link — Downlink Link parameters Unit Notes Carrier Frequency 401.50 MHz 401 — 402 MHz Carrier wavelength 0.75 ul Boltzmann constant —228.6 dBW/K/Hz BASIC PARAMETERS Orbit height 500 km Earth radius 6371 km Horizon height ToR distance 2573 km Satellite Segment Tx antenna gain 0.0 dBi Tx RF power 1.0 W Tx losses 0.5 dB Cable and connector Tx EIRP dBw PROPAGATION Satellite Antenna Pointing Loss 0.0 dB Polarization Loss 3.0 dB Worst—case Free space losses 152.7 dB Atmospheric Loss 2.1 dB lonospheric Loss 0.4 dB Total Propagation Losses 158.2 dB Ground Segment GS Antenna Pointing Loss 0.5 dB Antenna Gain 17.0 dBi Dual Crossed Yagis GS Transmission Line Losses 0.5 dB Worst—case at 0° Antenna Temperature 170 K elevation Ground Noise Temperature 300 K Estimate System Noise Temperature 470.0 System Noise Temperature 26.7 dBK Rx GIT ~10.7 dB/K Final C/No 59.2 dBHz

Receive Channel Bandwidth 28.8 kHz typically 1.5x bit rate Useful bitrate 19.2 kBit GMSK, Conv. R=1/2,K=7 & RS. Required Eb/No 4.80 dB (255,223) Demodulator phase Receiver Implementation Loss 3.00 dB offset C/No required 52.39 dBHz MARGIN A —> B dB

C. TT&C Contours Map Note that the contours at 2 dB below peak fall entirely beyond the edge of the visible Earth. 15

IV. Technical Certification I, David Morse, hereby certify that I am the technically qualified person responsible for the preparation of the technical information contained in the RBC Signals earth station license application and the accompanying Technical Appendix, that I am familiar with Part 25 of the Commission’s Rules (47 C.F.R. Part 25), and that I have either prepared or reviewed the technical information submitted in this application and found it to be complete and accurate to the best of my knowledge and belief. By: /s/David Morse Title: VP, Communication Systems Avaliant, LLC Date: January 29, 2018 16


Document Created: 2018-01-29 22:47:15
Document Modified: 2018-01-29 22:47:15
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