Attachment NBC_NV4_Engineering_

This document pretains to SES-LIC-20050513-00592 for License on a Satellite Earth Station filing.

IBFS_SESLIC2005051300592_431835

NBC Temporary Fixed Satellite Earth Station Environmental Impact / Radiation Hazard Study The attached FCC OET-65 RF Exposure Study analyzes the non-ionizing radiation levels for the proposed Transportable Ku-band Uplink utilizing a 1.5 meter Earth Station Antenna. The Study shows predicted RF power density in areas around the antenna and in the main beam when the Uplink is operating at its maximum power. The NBC Radio Frequency (RFR) Safety and Health Program establishes Safety Zones for Satellite News Gathering Trucks. In an area designated as a Red Zone, NBC authorized personel will be allowed to enter the area only after the emitter has been shut down or reduced in power to bring the RF power density in the area below maximum permissible exposure (MPE) limits for general population/uncontrolled environments. Areas are considered in the “Yellow Zone” if they have RF power densities at or above FCC MPE limits for general protection/uncontrolled environments but below the MPE limits for occupational/controlled environments or if they have the potential, should a transmission line leak or multiple on-demand antennas activate, to excced the MPE limits for general population/uncontrolled environments. Areas where RF power density does not exceed the FCC MPE limits for general population/uncontrolled environments are identified as Green zones. Only NBC authorized personnel that have received RF safety training, are fully aware, and are able to exercise control over their exposure to RF fields will be allowed in Yellow and Red zones. The NBC RFR Safety Zones for Remote Operations table defines any area in the main beam of an SNG truck antenna as a Red Zone. Areas where waveguide is exposed (panels open) is considered a Yellow zone. Warning signs attached to the vehicle warn individuals of the potential for hazardous radiation. RF power densities in the main beam of the antenna are predicted to exceed those specified in 47CFR §1.1310 for uncontrolled/public exposure at distances less than 147 meters from the antenna. At this minimum authorized antenna elevation angle, the main beam will be approximately 16 meters above ground. Operating procedures have been established for operational personnel to verify the antenna is not pointing at any building or populated area prior to energizing the antenna. Using FCC OET Bulletin 65 methods, off-axis near field power densities are calculated to be below MPE limits for general population/uncontrolled environments specified in specified in 47CFR §1.1310 at distances greater than 1.5 meters from the center of the satellite antenna. The center of the antenna is over 3.12 meters above ground and the antenna will not be used at elevation angles below 5 degrees, so based on the OET-65 calculations, people in areas around the Satellite News Gathering truck will not be exposed to power densities exceeding the MPE limits for general population/uncontrolled environments specified in specified in 47CFR §1.1310. Doug Lung, May 12, 2005

FCC OET-65 RF Exposure Study - Satellite Uplink Facility NBC News Burbank 1.5 meter Digital SNG Vehicle FCC Maximum Permissible Exposure Levels Source Units Public/uncontrolled area exposure limit 47CFR §1.1310 1 mW/cm2 Occupational/controlled area exposure limit 47CFR §1.1310 5 mW/cm2 Input Data Antenna Diameter datasheet 150.0 cm Antenna surface area calculated 17671 cm2 Feed flange diameter measured 8.890 cm Feed flange area calculated 62 cm2 Frequency (entry) 14250 MHz Wavelength (speed of light = 299,792,458 m/s) calculated 2.104 cm Transmit power at flange datasheet 70000 milliwatts Antenna gain datasheet 45.9 dBi Antenna gain factor calculated 38905 Height of base of antenna above ground measured 2.11 m Height of center of antenna above ground measured 3.12 m Minimum Elevation Angle (entry) 5 degrees Minimum Elevation Angle calculated 0.08727 radians FCC Maximum Permissible Exposure (MPE) Results calculated using FCC Bulletin OET-65 (Edition 97-01 August 1997) Uncontrolled Controlled Maximum power density at antenna surface Eq. 11 Pg 27 15.84 mW/cm2 Potential Hazard Potential Hazard Power density at feed flange Eq. 11 Pg 27 4510.91 mW/cm2 Potential Hazard Potential Hazard Extent of near-field Eq. 12 Pg 27 2674 cm Maximum new-field power density Eq. 13 Pg 28 12.29 mW/cm2 Potential Hazard Potential Hazard Aperture efficiency Eq. 14 Pg 28 0.78 Distance to beginning of far-field Eq. 16 Pg 29 6416.94 cm Power density at end of the transition regiion Eq. 17 Pg 29 5.12 mW/cm2 Potential Hazard Potential Hazard Maximum far-field power density Eq. 18 Pg 29 5.263 mW/cm2 Potential Hazard Potential Hazard Main Beam Far-field region safe exposure distances Minimum distance for public/uncontrolled exposure Eq. 18 Pg 29 147.21 meters Height at minimum antenna elevation angle calculated 15.95 meters Horizontal distance calculated 146.65 meters Minimum distance for occupational/controlled exposure Eq. 18 Pg 29 65.84 meters Height at minimum antenna elevation angle calculated 8.86 meters Horizontal distance calculated 65.58 meters Off-Axis Near Field/Transition Region safe exposure distances from antenna (20 dB reduction in power density at distances greater than one antenna diameter from the main beam center.) OET-65 Pg 30 Maximum off-axis near field power density Eq. 13 Pg 28 0.1229 mW/cm2 Below FCC MPE Below FCC MPE Public/uncontrolled exposure off-axis distance Diam/or Eq 17 1.5 meters Occupatonal/controlled exposure off-axis distance Diam/or Eq 17 1.5 meters Off-Axis Far Field safe exposure distances from the antenna (Based on side lobe attenuation required by FCC 25.209(a)(2)) Angle off main beam axis (1 to 48 degrees) (entry) 1 degree(s) Off-axis antenna gain factor OET-65 Pg 30* 1585 Minimum distance for public/uncontrolled exposure Eq. 18 Pg 29 ** 64.17 meters * Gain converted from dBi to linear multiple ** If calculated distance is less than the start of the far field region, the distance to the start of the far field region is used. Analysis by Doug Lung, May 12, 2005


Document Created: 2005-05-12 09:23:00
Document Modified: 2005-05-12 09:23:00
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