Attachment Rad_Hazard

This document pretains to SES-LIC-20100817-01141 for License on a Satellite Earth Station filing.

IBFS_SESLIC2010081701141_831792

Exhibit A Page 1 of 17 9/22/09 20090915MV05_FSS4180LP_Rad_Hazard.doc RF Radiation Analysis for Datron FSS-4180 LP Ku Band Communications-on-the-Move (COTM) Antenna System 20090915MV05_FSS4180LP_Rad_Hazard.doc September 22, 2009 Prepared by Intellicom Technologies, Inc. for L3 Communications iNTELLICOM Satellite & Wireless Engineering and Management www.ITCcom.net

Exhibit A Page 2 of 17 9/22/09 20090915MV05_FSS4180LP_Rad_Hazard.doc Table of Contents 1.0 INTRODUCTION........................................................................................4 1.1 Assumptions used for this Analysis .......................................................................................... 6 2.0 ANALYSIS .................................................................................................9 2.1 Far Field Distance Calculation ................................................................................................. 9 2.2 Safe Far Field Distance Calculation ......................................................................................... 9 2.3 Near Field Distance Calculation ............................................................................................... 9 2.4 Transition Region Calculation................................................................................................ 10 2.5 Region between Main Reflector and Sub-reflector ................................................................ 10 2.6 Main Reflector Region ............................................................................................................ 10 2.7 Region between Main Reflector and Ground ......................................................................... 10 2.8 Safe Distances from Antenna.................................................................................................. 11 3.0 SUMMARY AND CONCLUSIONS ..........................................................14 3.1 Conclusions ............................................................................................................................. 14 3.2 Manufacturer Responsibility .................................................................................................. 15 3.2 Operator Responsibility.......................................................................................................... 17 iNTELLICOM Satellite & Wireless Engineering and Management www.ITCcom.net

Exhibit A Page 3 of 17 9/22/09 20090915MV05_FSS4180LP_Rad_Hazard.doc List of Figures Figure 1- Mounting of COTM Antenna on a HMMWV...........................................6 Figure 2 - Height at the Platform of a Stryker........................................................6 Figure 3 - Height at the Platform of a Bradley.......................................................7 Figure 4 - Height at the Rooftop of an Ambulance (Type III).................................7 Figure 5 - Antenna Beam Relative to Personnel .................................................11 Figure 6 - Radiation Keep out Zone - No Elevation Limit ....................................13 Figure 7 - Radiation Keep out Zone - 20o Elevation Limit ...................................13 Figure 8 - Radiation Hazard Warning Label Sample...........................................16 List of Tables Table 1 - Maximum Permissible Exposure Limits .................................................4 Table 2 - Formulas and Parameters Used in this Document ................................5 Table 3 - Summary of Expected Radiation Levels ..............................................14 Table 4 - Radiation Hazard Area.........................................................................14 iNTELLICOM Satellite & Wireless Engineering and Management www.ITCcom.net

Exhibit A Page 4 of 17 9/22/09 20090915MV05_FSS4180LP_Rad_Hazard.doc 1.0 INTRODUCTION This report is in response to the original 1985 FCC adoption of the 1982 American National Standards Institute (ANSI) guidelines and the further 1993 adoption of the 1992 ANSI and 1991 1 Institute of Electrical and Electronics Engineers (IEEE) guidelines for evaluating exposure to RF transmitters licensed and authorized by the FCC. In 1996, the FCC adapted a modified version 2 of its original proposal , which also fulfills the requirements of the Telecommunications Act of 3 1996 RF exposure guidelines . The Maximum Permissible Exposure (MPE) radiation limit specifies two separate tiers as shown in Table 1: • (A) Occupational/Controlled Exposure: The time-averaged exposure period is 6 minutes. • (B) General Population/Uncontrolled Exposure: The time-averaged exposure period is 30 minutes. Table 1 - Maximum Permissible Exposure Limits (A) Controlled Exposure (B) Uncontrolled Exposure (6-Minute Average) (30-Minute Average) Frequency Electric Field Magnetic Power Electric Field Magnetic Power Range Strength (E) Field Strength Density (S) Strength (E) Field Strength Density (S) 2 2 (MHz) (V/m) (H) (A/m) (mW/cm ) (V/m) (H) (A/m) (mW/cm ) 0.3-3.0 614 1.63 (100)* 2 3.0-30 1842/f 4.89/f (900/f )* 0.3-1.34 614 1.63 (100)* 1.34-30 824/f 2.19/f (180/f 2)* 30-300 61.4 0.163 1.0 27.5 0.073 0.2 300-1500 -- -- f/300 -- -- f/1500 1,500- -- -- 5 -- -- 1.0 100,000 F = frequency in MHz * = Plane Wave equivalent Power Density -- = Not specified. 1 ANSI/IEEE C95.1-1992 (IEEE Standard for Safety Levels with Respect to Human Exposure to RF Electromagnetic Fields, 3 kHz to 300 GHz) 2 Refer to ET Docket 93-62 References 55 and 56, and FCC Office of Engineering (OET) Bulletin 65 Reference 57 Edition 97-01 for detailed information. 3 See Section 704(b) of the Telecommunications Act of 1996, Pub. L No 104-104, Stat 56. iNTELLICOM Satellite & Wireless Engineering and Management www.ITCcom.net

Exhibit A Page 5 of 17 9/22/09 20090915MV05_FSS4180LP_Rad_Hazard.doc The satellite earth station being analyzed in this report is a dual optics parabolic antenna that 4 communicates via geosynchronous Ku band satellites. It is designed to be mounted on the rooftop of vehicles and operate while the vehicle is in motion over rough terrain. Precision tracking methods using an Inertial Navigation Unit and GPS tracking maintain the antenna pointing accuracy to within a few 10ths of a degree of boresight. The antenna is protected from the elements by an RF translucent radome. The earth station is intended to support receive data rates in excess of 1.544 Mbps, and 512 kbps for transmit. Sophisticated software algorithms include the automatic shutdown of RF transmissions when the following conditions exist: 1. When the antenna boresight error is greater than a several 10ths of a degree. This error is in Azimuth or Elevation, or a combination of both. This is a settable parameter. o o 2. When the elevation angle goes below a preprogrammed value (usually 5 to 20 ) or mask. 3. When the received signal is no longer available (blocked) and the demodulator fails to lock onto the signal. The purpose of this analysis is to determine the Power Flux Density (S) for the earth station and to compare these levels to the specified MPE’s of Table 1. Several formulas and parameters to be used for determining the Power Flux Densities are provided in Table 2. Table 2 - Formulas and Parameters Used in this Document 4 13.75 to 14.50 GHz Transmit, 10.95 to 12.75 GHz Receive iNTELLICOM Satellite & Wireless Engineering and Management www.ITCcom.net

Exhibit A Page 6 of 17 9/22/09 20090915MV05_FSS4180LP_Rad_Hazard.doc 1.1 Assumptions used for this Analysis This antenna system is designed to be mounted on the rooftop of vehicles that can communicate, while on-the-move, with a hub antenna via Ku band satellites. It is important to identify the majority of the types of vehicles that are destined to be the platform for this antenna, and to analyze the antenna profile as it applies to those vehicles. The primary usage is the US Military, particularly the Army and Marine divisions. The vehicles include, but are not limited to, the HMMWV, the Stryker, and the Bradley. A possibility of other vehicles of a commercial nature could also be chosen; in particular, emergency vehicles, such as ambulances and paramedic rescue vehicles. Photos of these vehicles are presented in Figures 1, 2, 3 and 4. The vehicle height is shown in each of these photos. Figure 1- Mounting of COTM Antenna on a HMMWV 8.72 ft Figure 2 - Height at the Platform of a Stryker iNTELLICOM Satellite & Wireless Engineering and Management www.ITCcom.net

Exhibit A Page 7 of 17 9/22/09 20090915MV05_FSS4180LP_Rad_Hazard.doc 11.8 ft Figure 3 - Height at the Platform of a Bradley 81.8” Figure 4 - Height at the Rooftop of an Ambulance (Type III) The lowest profile vehicle of the vehicles considered here is the Army’s and Marine’s HMMWV. It is this vehicle that is the basis for the following analysis. In the HMMWV photo, Figures 1, is shown the antenna in question, overlaid with an approximate radiation pattern of the main lobe and its two significant sidelobes. The HMMWV has a height of 74” (6’ 2”) measured from ground to the rooftop. Secondly, the o antenna boresight (if pointed at 0 elevation) rises another 8” above the platform (rooftop). The total width of the vehicle is 86”, so the center of the rooftop to the vehicle edge is 43”. Assuming that the lowest elevation angle (relative to the vehicle rooftop) that the antenna system is allowed o to transmit is 20 , the height of the beam at boresight is calculated with the following formula: Height of boresight @ vehicle edge is = 43” * TAN 20o = 15.7” o o However, the elevation beamwidth of the main lobe is 8 (null to null), or 4 on each side of boresight. So the minimum height of the main beam @ vehicle edge is: 43” * Tan (20o – 4o) = 12.3” The elevation sidelobes on either side of boresight are at 8o (main lobe axis to 2nd null). So the minimum height of the lower sidelobe @ vehicle edge becomes: 43” * Tan (20o – 8o) = 9.1” iNTELLICOM Satellite & Wireless Engineering and Management www.ITCcom.net

Exhibit A Page 8 of 17 9/22/09 20090915MV05_FSS4180LP_Rad_Hazard.doc Adding these heights to the vehicle height plus the antenna boresight from the platform thus becomes: Minimum main beam height @ vehicle edge 74” + 8” + 12.3” = 94.3”, or ~ 7’ 10” Minimum sidelobe height @ vehicle edge 74” + 8” + 9.1” = 91.1”, or ~ 7’ 7” The height of the main beam at a distance of 10’ away from the center of the antenna would be as follows: o o Height of boresight @ 10’ 120” *Tan (20 -4 ) = 34.4 Minimum main beam height @ 10’ 74” + 8” + 34.4” = 116.4”, or ~ 9’ 8” The height of the sidelobe at a distance of 10’ away from the center of the antenna would be as follows: o o Height of sidelobe @ 10’ 120” *Tan (20 -8 ) = 25.5” Minimum sidelobe height @ 10’ 74” + 8” + 25.5” = 107.5”, or ~ 8’ 12” This analysis shows that it is not easy to prevent the general public (Uncontrolled Exposure) or the occupational (Controlled Exposure) from maintaining a safe distance away from the vehicle. Further, those personnel entering and exiting the vehicle are well within the high power of the main beam and lower adjacent sidelobes of the antenna. It is this area that poses the greatest hazard. It is further exacerbated by the protective dome that surrounds the antenna, since it totally conceals the antenna’s direction. Those who may be in close proximity to the vehicle could be in a direct path of the main beam, and be exposed to harmful RF radiation. As a safety measure, the manufacturer of the antenna shall: • o pre-set a 20 elevation (relative to the vehicle rooftop) transmit limit on the antenna • provide warnings to the operator in the manual and in the GUI should the operator choose to override or change these settings iNTELLICOM Satellite & Wireless Engineering and Management www.ITCcom.net

Exhibit A Page 9 of 17 9/22/09 20090915MV05_FSS4180LP_Rad_Hazard.doc 2.0 ANALYSIS 2.1 Far Field Distance Calculation In the Far Field or Fraunhofer region of the antenna, the power density decreases inversely with the square of the distance from the main reflector. The distance to the beginning of the far field 5,6 is : 7 The maximum main beam power density at the beginning of the far field is : 2.2 Safe Far Field Distance Calculation It is important to know the minimum distance from the center of the antenna to where the Uncontrolled Exposure Power Density (S) in (mW/cm2) is considered safe. Per FCC OET 2 o Bulletin 65, a safe limit for uncontrolled exposure is 1.0 mW/cm . For a 0 elevation angle, the minimum distance at which this level is achieved is: 2.3 Near Field Distance Calculation In the radiating Near Field region, the average power density remains fairly constant at different distances from the antenna, although there are localized energy fluctuations. This area is called the Fresnel Region, or the focusing region of the antenna. The distance to the end of the Near Field is8: The maximum power density in the Near Field is9: 5 OET Bulletin 65 Edition 97-01 dated August 1997, Formula (16). 6 D1 = Width; D2 = Height 7 OET Bulletin 65 Edition 97-01 dated August 1997, Formula (18). 8 OET Bulletin 65 Edition 97-01 dated August 1997, Formula (12). 9 OET Bulletin 65 Edition 97-01 dated August 1997, Formula (13). iNTELLICOM Satellite & Wireless Engineering and Management www.ITCcom.net

Exhibit A Page 10 of 17 9/22/09 20090915MV05_FSS4180LP_Rad_Hazard.doc 2.4 Transition Region Calculation The area between the Near and Far Field regions is called the Transition region. Power density in this region decreases inversely with the distance from the antenna. This region extends from Rnf to Rff. The power density at a distance Rt in this region can be determined from the following equation10: 2.5 Region between Main Reflector and Sub-reflector The energy between the sub-reflector and the main reflector of a Cassegrain antenna can be calculated by determining the Power Density at the sub-reflector surface. This can be determined : from the following equation 2.6 Main Reflector Region 11 Power Density in the main reflector can be determined from the following equation : 2.7 Region between Main Reflector and Ground Assuming uniform illumination of the main reflector surface, the Power Density between the antenna and the ground can be determined from the following equation: 10 OET Bulletin 65 Edition 97-01 dated August 1997, Formula (17). 11 OET Bulletin 65 Edition 97-01 dated August 1997, Formula (11). iNTELLICOM Satellite & Wireless Engineering and Management www.ITCcom.net

Exhibit A Page 11 of 17 9/22/09 20090915MV05_FSS4180LP_Rad_Hazard.doc 2.8 Safe Distances from Antenna Following are calculations for determining the minimum safe distance a person must be away from the transmitting antenna. Per FCC OET Bulletin 65, a safe limit for uncontrolled exposure is 2 1.0 mW/cm . At the distances to be calculated, the power density will be less than or equal to 2. 1.0 mW/cm For the following calculations, it is assumed that a person would be at or below the level of the antenna. • With no elevation limits, personnel must be over 65 ft away from the main beam. Since a radome covers the antenna, one would not be certain where the antenna is pointing. • With elevation limits of 20 or greater, a safe distance would be 2 ft away from the o antenna in any direction as long as personnel are below the level of the antenna. Note that if the vehicle is not level with the ground, it is possible for personnel to be at or above the antenna level. As a precaution, the operator must ensure that personnel are over 65 feet away if they are at or above the antenna level. Figure 5 - Antenna Beam Relative to Personnel iNTELLICOM Satellite & Wireless Engineering and Management www.ITCcom.net

Exhibit A Page 12 of 17 9/22/09 20090915MV05_FSS4180LP_Rad_Hazard.doc iNTELLICOM Satellite & Wireless Engineering and Management www.ITCcom.net

Exhibit A Page 13 of 17 9/22/09 20090915MV05_FSS4180LP_Rad_Hazard.doc The following figures show the area that personnel must stay out of to be at or below 1.0 2 mW/cm . Figure 6 - Radiation Keep out Zone - No Figure 7 - Radiation Keep out Zone - Elevation Limit 20o Elevation Limit • Red shows keep out zone • Red shows keep out zone • Green Shows a simplified keep out zone • Green Shows a simplified keep out zone iNTELLICOM Satellite & Wireless Engineering and Management www.ITCcom.net

Exhibit A Page 14 of 17 9/22/09 20090915MV05_FSS4180LP_Rad_Hazard.doc 3.0 SUMMARY AND CONCLUSIONS 3.1 Conclusions Table 3 provides the summary of the previous calculations and the expected radiation levels. Based upon the above analysis, it is concluded that harmful levels of radiation levels exist in all regions identified in Table 3. This hazardous exposure applies to those who may be around the antenna while it is transmitting. Table 3 - Summary of Expected Radiation Levels Table – 4 provides a simplified summary of the radiation hazard area. It is recommended that the operator perform radiation flux density measurements around the antenna during typical operation to verify the area of hazard to personnel and ensure that personnel are restricted from entering the hazard area. Table 4 - Radiation Hazard Area Radiation Hazard Area IF IF • • o no elevation limits are used elevation limits of 20 or greater are • or if personnel are at or above the level used of the antenna • and personnel are below the level of the antenna THEN THEN 1. Keep a distance of 65 ft or more 1. Keep a distance of 2 ft or more 2. This area shall be roped off around 2. Access to this area shall be restricted the antenna, and radiation hazard and radiation hazard signs shall be signs shall be posted during the posted during the operation of this operation of this antenna. antenna. 3. Operator shall perform measurements 3. Operator shall perform measurements to verify hazard area. to verify hazard area. iNTELLICOM Satellite & Wireless Engineering and Management www.ITCcom.net

Exhibit A Page 15 of 17 9/22/09 20090915MV05_FSS4180LP_Rad_Hazard.doc 3.2 Manufacturer Responsibility 1. The manufacturer shall advise the owner/operator to have or seek sufficient knowledge on the safe operation of radio transmitters. 2. The manufacturer shall be responsible for installing permanent RF hazard warning labels on the antenna housing, similar to the one in Figure 5. 3. Radiation hazard warnings signs shall be of sufficient size and in clear view of personnel nearby. 4. Labels shall include a diagram (similar to Figures 6, 7) showing the regions around the 2 earth station where the levels could exceed 1.0 mW/cm . 5. The manufacturer shall include warnings in the Operation, Installation, and Maintenance Manuals furnished with each antenna system regarding the potential hazard from RF radiation. 6. The manufacturer shall impose elevation restrictions that turns off the RF transmission when the antenna elevation movements fall below the above specified limits (Table-4). 7. The manufacturer shall pre-program the antenna system with elevation restrictions (Table-4) before delivery. 8. The manufacturer shall provide safety warnings to the operator regarding reducing or removing elevation restrictions. 9. The manufacturer shall maintain this document particularly if parameters of the transmission system change which could impact safety. 10. If a system is delivered that includes a modem and an antenna system, the manufacturer shall ensure that the system is muted within 3 seconds if it is not locked to a receive signal. 11. The manufacturer shall include warnings that an operational system shall include a modem that mutes its transmitter within 3 seconds if it is not locked to a receive signal. 12. The manufacturer shall provide updated labels and documentation to all customers if the safety information is revised. 13. The manufacturer shall recommend that the operator perform a radiation safety test of the areas in which personnel will be located during transmission. If radiation exceeds recommended levels, all transmission shall cease until radiation levels have been corrected. iNTELLICOM Satellite & Wireless Engineering and Management www.ITCcom.net

Exhibit A Page 16 of 17 9/22/09 20090915MV05_FSS4180LP_Rad_Hazard.doc Figure 8 - Radiation Hazard Warning Label Sample iNTELLICOM Satellite & Wireless Engineering and Management www.ITCcom.net

Exhibit A Page 17 of 17 9/22/09 20090915MV05_FSS4180LP_Rad_Hazard.doc 3.2 Operator Responsibility 1. The operator shall have sufficient knowledge or seek training on the safe operation of radio transmitters. 2. The operator shall adhere to the warnings provided by the manufacturer’s labels, manuals, updates, or other documentation. 3. The operator shall keep the labels on the antenna platform in good shape and within clear view of anyone within close proximity. 4. The operator shall ensure that individuals will be prevented from straying within the hazard region (Table-4) by means of signs, fencing or caution tape, verbal warnings, and placement of the earth station or other appropriate means so as to minimize access to the hazardous region. 5. The operator shall perform a visual inspection of the area around the antenna within the hazard area to ensure that all personnel are below the antenna base and removed from the hazard area (Table-4) during transmission. 6. The operator shall ensure that the antenna system is configured with elevation restrictions (Table-4) that turn off the RF transmission when the antenna elevation falls below the above specified limits (Table-4). 7. The operator shall ensure that the system mutes its transmitter within 3 seconds if it is not locked to a receive signal. 8. The operator shall perform a radiation safety test of the areas in which personnel will be located during transmission. If radiation exceeds recommended levels, all transmission shall cease until radiation levels have been corrected. iNTELLICOM Satellite & Wireless Engineering and Management www.ITCcom.net


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Document Modified: 2019-04-23 15:23:30
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