HomeMy WebLinkAbout2017-06-05 Cell Emissions Report Frances Helen Rd.
C Squared Systems, LLC
65 Dartmouth Drive
Auburn, NH 03032
(603) 644-2800
support@csquaredsystems.com
Calculated Radio Frequency Emissions Report
Yarmouth 2 MA
Frances-Helen Road, Yarmouth, MA 02675
June 5, 2017
i
Table of Contents
1. Introduction ..................................................................................................................................................................................... 1
2. FCC Guidelines for Evaluating RF Radiation Exposure Limits ......................................................................................... 1
3. RF Exposure Calculation Methods ............................................................................................................................................ 2
4. Antenna Inventory ......................................................................................................................................................................... 3
5. Calculation Results ........................................................................................................................................................................ 4
6. Conclusion ....................................................................................................................................................................................... 6
7. Statement of Certification ............................................................................................................................................................ 6
Attachment A: References ................................................................................................................................................................. 7
Attachment B: FCC Limits for Maximum Permissible Exposure (MPE) .............................................................................. 8
Attachment C: Verizon Wireless’ Antenna Model Data Sheets and Electrical Patterns ................................................... 10
List of Figures
Figure 1: Graph of Percent of General Population MPE vs. Distance .......................................................................... 4
Figure 2: Graph of FCC Limits for Maximum Permissible Exposure .......................................................................... 9
List of Tables
Table 1: Proposed Antenna Inventory ......................................................................................................................... 3
Table 2: Maximum Percent of General Population Exposure Values ......................................................................... 5
Table 3: FCC Limits for Maximum Permissible Exposure .......................................................................................... 8
Yarmouth 2 MA 1 June 5, 2017
1. Introduction
The purpose of this report is to investigate compliance with applicable FCC regulations for the installation of Verizon
Wireless antenna arrays on the existing NSTAR transmission tower (#36) located off Frances-Helen Road in Yarmouth,
MA. The coordinates of the tower are 41° 42' 13.00" N, 70° 13' 02.91" W.
Verizon Wireless is proposing the following:
1) Install 6 dual band antennas for their LTE network (two per sector);
This report uses the planned antenna configuration for Verizon Wireless to derive the resulting % MPE, once the proposed
installation has been completed.
2. FCC Guidelines for Evaluating RF Radiation Exposure Limits
In 1985, the FCC established rules to regulate radio frequency (RF) exposure from FCC licensed antenna facilities. In
1996, the FCC updated these rules, which were further amended in August 1997 by OET Bulletin 65 Edition 97-01. These
new rules include Maximum Permissible Exposure (MPE) limits for transmitters operating between 300 kHz and 100
GHz. The FCC MPE limits are based upon those recommended by the National Council on Radiation Protection and
Measurements (NCRP), developed by the Institute of Electrical and Electronics Engineers, Inc., (IEEE) and adopted by the
American National Standards Institute (ANSI).
The FCC general population/uncontrolled limits set the maximum exposure to which most people may be subjected.
General population/uncontrolled exposures apply in situations in which the general public may be exposed, or in which
persons that are exposed as a consequence of their employment may not be fully aware of the potential for exposure or
cannot exercise control over their exposure.
Public exposure to radio frequencies is regulated and enforced in units of milliwatts per square centimeter (mW/cm2). The
general population exposure limits for the various frequency ranges are defined in the attached “FCC Limits for Maximum
Permissible Exposure (MPE)” in Attachment B of this report.
Higher exposure limits are permitted under the occupational/controlled exposure category, but only for persons who are
exposed as a consequence of their employment and who have been made fully aware of the potential for exposure, and
they must be able to exercise control over their exposure. General population/uncontrolled limits are five times more
stringent than the levels that are acceptable for occupational, or radio frequency trained individuals. Attachment B contains
excerpts from OET Bulletin 65 and defines the Maximum Exposure Limit.
Finally, it should be noted that the MPE limits adopted by the FCC for both general population/uncontrolled exposure and
for occupational/controlled exposure incorporate a substantial margin of safety and have been established to be well below
levels generally accepted as having the potential to cause adverse health effects.
Yarmouth 2 MA 2 June 5, 2017
3. RF Exposure Calculation Methods
The calculation results displayed in the following figures were generated using the following formula as outlined in FCC
bulletin OET 65:
Loss Beam Off Density Power 2 ×
×=R
EIRP
π
Where:
EIRP = Effective Isotropic Radiated Power
R = Radial Distance = ()22VH+
H = Horizontal Distance from antenna in meters
V = Vertical Distance from radiation center of antenna in meters
Off Beam Loss is determined by the selected antenna patterns
Ground reflection factor of 2.0
These calculations assume that the antennas are operating at 100 percent capacity, that all antenna channels are
transmitting simultaneously, and that the radio transmitters are operating at full power. Obstructions (trees, buildings, etc.)
that would normally attenuate the signal are not taken into account. The calculations assume even terrain in the area of
study and do not take into account actual terrain elevations which could attenuate the signal. As a result, the predicted
signal levels reported below are much higher than the actual signal levels will be from the final configuration.
The percent of MPE values presented in this report reflect levels that one may encounter from one sector of antennas. Most
carriers use three sectors per site with azimuths approximately 120 degrees apart, therefore one could not be standing in
the main beam of all three sectors at the same time. In cases where downtilt and antenna models are not uniform across all
three sectors, the downtilt and antenna model with the highest gain was used for the calculations. This results in a
conservative or “worst case” assumption for percent of MPE calculations.
Yarmouth 2 MA 3 June 5, 2017
4. Antenna Inventory
Table 1 below outlines Verizon Wireless’ proposed antenna configuration for the site. The associated data sheets and
antenna patterns for these specific antenna models are included in Attachment C.
Operator Sector TX Freq (MHz)
Power at Antenna (Watts)
Ant Gain (dBi)
Power EIRP (Watts) Antenna Model Beam Width Mech. Tilt Length (ft)
Antenna Centerline Height (ft)
Verizon
Alpha 751 120 13.9 2946 X7CAP-465-VR0-IPB_4 67 0 4.2 62.2 2100 180 16.7 8419 X7CAP-465-VR0-IPB_1 60 0 4.2 62.2
Beta 751 120 13.9 2946 X7CAP-465-VR0-IPB_4 67 0 4.2 62.2
2100 180 16.7 8419 X7CAP-465-VR0-IPB_1 60 0 4.2 62.2
Gamma 751 120 13.9 2946 X7CAP-465-VR0-IPB_4 67 0 4.2 62.2 2100 180 16.7 8419 X7CAP-465-VR0-IPB_1 60 0 4.2 62.2
Table 1: Proposed Antenna Inventory1 2
1 Antenna heights are in reference to the Chappell Engineering Associates, LLC Lease Exhibit, dated January 20, 2017.
2 Transmit power assumes 0 dB of cable loss.
Yarmouth 2 MA 4 June 5, 2017
5. Calculation Results
The calculated power density results are shown in Figure 1 below. For completeness, the calculations for this analysis
range from 0 feet horizontal distance (directly below the antennas) to a value of 2,000 feet horizontal distance from the
site. In addition to the other worst case scenario considerations that were previously mentioned, the power density
calculations to each horizontal distance point away from the antennas was completed using a local maximum off beam
antenna gain (within ± 5 degrees of the true mathematical angle) to incorporate a realistic worst-case scenario.
Figure 1: Graph of Percent of General Population MPE vs. Distance
The highest percent of MPE (3.52% of the General Population limit) was calculated to occur at a horizontal distance of
196 feet from the site. Please note that the percent of MPE calculations close to the site take into account off beam loss,
which is determined from the vertical pattern of the antenna used. Therefore, RF power density levels may increase as the
distance from the site increases. At distances of approximately 500 feet and beyond, one would now be in the main beam
of the antenna pattern and off beam loss is no longer considered. Beyond this point, RF levels become calculated solely on
distance from the site and the percent of MPE decreases significantly as distance from the site increases.
0.00%
0.50%
1.00%
1.50%
2.00%
2.50%
3.00%
3.50%
4.00%
0 200 400 600 800 1000 1200 1400 1600 1800 2000% General Population MPEHorizontal Distance (feet)
Calculated %MPE vs. Horizontal Distance from Source
Verizon LTE 751 MHz Verizon LTE 2100 MHz Max MPE Combined
Yarmouth 2 MA 5 June 5, 2017
Table 2 below lists percent of MPE values as well as the associated parameters that were included in the calculations. The
highest percent of MPE value was calculated to occur at a horizontal distance of 196 feet from the site (reference
Figure 1).
As stated in Section 3, all calculations assume that the antennas are operating at 100 percent capacity, that all antenna
channels are transmitting simultaneously, and that the radio transmitters are operating at full power. Obstructions (trees,
buildings etc.) that would normally attenuate the signal are not taken into account. In addition, a 6-foot height offset was
considered in this analysis to account for average human height. As a result, the predicted signal levels are significantly
higher than the actual signal levels will be from the final configuration. The results presented in Figure 1 and Table 2
assume level ground elevation from the base of the tower out to the horizontal distances calculated.
Carrier Number of Trans.
Power out of Base Station Per Transmitter
(Watts)
Antenna Height (Feet)
Distance to the Base of Antennas
(Feet)
Power Density (mW/cm2)
Limit
(mW/cm2) %MPE
Verizon LTE 2100
MHz 2 90.0 62.2 196 0.002731 1.000 0.27%
Verizon LTE 751 MHz 2 60.0 62.2 196 0.016226 0.500 3.25%
Total 3.52%
Table 2: Maximum Percent of General Population Exposure Values3 4
3 Transmit power assumes 0 dB of cable loss.
4 Frequencies listed in Table 2 are representative of the operating band of Verizon Wireless and are not the carriers’ specific operating
frequency.
Yarmouth 2 MA 6 June 5, 2017
6. Conclusion
The above analysis verifies that RF exposure levels from the proposed Verizon Wireless antenna configuration will be
well below the maximum levels as outlined by the FCC in the OET Bulletin 65 Ed. 97-01. Using the conservative
calculation methods and parameters detailed above, the maximum percent of MPE calculated at 6 feet above ground level
is 3.52% of the FCC General Population limit. This maximum percent of MPE value is calculated to occur 196 feet
away from the site.
7. Statement of Certification
I certify to the best of my knowledge that the statements in this report are true and accurate. The calculations follow
guidelines set forth in ANSI/IEEE Std. C95.3, ANSI/IEEE Std. C95.1 and FCC OET Bulletin 65 Edition 97-01.
____________________________ June 2, 2017
Keith Vellante
RF Engineer
C Squared Systems, LLC
Date
Yarmouth 2 MA 7 June 5, 2017
Attachment A: References
OET Bulletin 65 - Edition 97-01 - August 1997 Federal Communications Commission Office of Engineering & Technology
IEEE C95.1-2005, IEEE Standard Safety Levels With Respect to Human Exposure to Radio Frequency Electromagnetic
Fields, 3 kHz to 300 GHz IEEE-SA Standards Board
IEEE C95.3-2002 (R2008), IEEE Recommended Practice for Measurements and Computations of Radio Frequency
Electromagnetic Fields With Respect to Human Exposure to Such Fields, 100 kHz-300 GHz IEEE-SA Standards Board
Yarmouth 2 MA 8 June 5, 2017
Attachment B: FCC Limits for Maximum Permissible Exposure (MPE)
(A) Limits for Occupational/Controlled Exposure5
Frequency
Range
(MHz)
Electric Field
Strength (E)
(V/m)
Magnetic Field
Strength (E)
(A/m)
Power Density (S) (mW/cm2) Averaging Time |E|2, |H|2 or S (minutes)
0.3-3.0 614 1.63 (100)* 6
3.0-30 1842/f 4.89/f (900/f2)* 6
30-300 61.4 0.163 1.0 6
300-1500 - - f/300 6
1500-100,000 - - 5 6
(B) Limits for General Population/Uncontrolled Exposure6
Frequency
Range (MHz)
Electric Field
Strength (E) (V/m)
Magnetic Field
Strength (E) (A/m)
Power Density (S)
(mW/cm2)
Averaging Time
|E|2, |H|2 or S (minutes)
0.3-1.34 614 1.63 (100)* 30
1.34-30 824/f 2.19/f (180/f2)* 30
30-300 27.5 0.073 0.2 30
300-1500 - - f/1500 30
1500-100,000 - - 1.0 30
f = frequency in MHz * Plane-wave equivalent power density
Table 3: FCC Limits for Maximum Permissible Exposure
5 Occupational/controlled limits apply in situations in which persons are exposed as a consequence of their employment provided those
persons are fully aware of the potential for exposure and can exercise control over their exposure. Limits for occupational/controlled
exposure also apply in situations when an individual is transient through a location where occupational/controlled limits apply provided he or
she is made aware of the potential for exposure.
6 General population/uncontrolled exposures apply in situations in which the general public may be exposed, or in which persons that are
exposed as a consequence of their employment may not be fully aware of the potential for exposure or cannot exercise control over their
exposure.
Yarmouth 2 MA 9 June 5, 2017
Plane-wave Equivalent Power Density
Frequency (MHz)
Figure 2: Graph of FCC Limits for Maximum Permissible Exposure
1.34 100,000 1,500
Yarmouth 2 MA 10 June 5, 2017
Attachment C: Verizon Wireless’ Antenna Model Data Sheets and Electrical Patterns
751 MHz LTE
Manufacturer: JMA
Model #: X7CAP-465-VR0-IPB_4
Frequency Band: 698-824 MHz
Gain: 13.9 dBi
Vertical Beamwidth: 17.1°
Horizontal Beamwidth: 67°
Polarization: ± 45°
Size L x W x D: 50.5” x 12.5” x 7.1”
2100 MHz LTE
Manufacturer: JMA
Model #: X7CAP-465-VR0-IPB_1
Frequency Band: 1920-2170 MHz
Gain: 16.7 dBi
Vertical Beamwidth: 6.7°
Horizontal Beamwidth: 60°
Polarization: ± 45°
Size L x W x D: 50.5” x 12.5” x 7.1”