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RADIO FREQUENCY EMISSIONS ANALYSIS REPORT
EVALUATION OF HUMAN EXPOSURE POTENTIAL
SD03XC154 { Ground Level)
Sprint PCS®
Prepared By:
Sprint PCS
11880 College Blvd
Overland Park, Kansas 66210
913-315-2383
Michael D. Lawson
January 11, 2002
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Table of Contents
1.0 Executive Summary .......•....•.•.•.•.•.•.....•.••.......•.........................•..•...•.•........•.•.•..•.•...........•....••....•. 1
2.0 Site Description ••.....•...•.........•.•...•......•.•......................•.......•.•.•..........•...•.........•....•........•.••..•...•••• 4
2.1 Communications Systems .••..•.•.•.•......•.•.•....•........•..•.......••••.......••...•..•.••••..•.•.••.•..•.••••••..•.•••.•.•.. 5
2.2 Antenna Systems .•.•.•.•.•.•.•.•.•••.•.•.•.•..•.•......•.•...•..•.•.•..•••.•.•.•.•••.•.•.•.•••.•...•.••••..•..•••.•..•....•••.•.•.•••••.• 5
3.0 Transmitter Frequencies ..•.•.•.....•..•.•..•.•........•••..•.•.••.•...•.•.•.•••.•.•.•.••.•.•....••.•..•..•.•..•....•...•••...•••.•. 5
4.0 Maximum Permissible Emission Analysis ............................................................................ 6
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1.0 Executive Summary
This report presents non-ionizing radio frequency (RF) emissions analysis, which predicts the
Maximum Permissible Exposure (MPE) potential to humans at or near wireless communication
sites. The predicted RF emissions are evaluated against acceptable MPE limits as defined by
specific established standards. The analysis then determines if the communications site is in
compliance with Federal Communication Commission (FCC) regulations or other standards
regarding safe human exposure to radio frequency radiation.
The analysis was performed on the SD03XC154 site/tower. This site consists two
providers, NEXTEL and Sprint PCS. This is a monopalm installation with Sprint PCS,
located at 17 feet AGL, using a two sector configuration with one transmit antenna per
sector and Nextel, located at 30 feet AGL, using a 3 sector configuration with one
transmit antenna per sector. The report consists of Sections that provide details of the
communications site, antenna systems, operational frequencies, MPE analysis and associated
Appendices.
The analysis was performed with the setup options depicted in the Table below.
Analysis Description
MPE Standard FCCOET65
Site Configuration Off Tower
Analysis Model Near Field
T_ype of Analy_sis All Systems
Antenna Patterns Considered Yes
Measured Antenna Isolation Data No
Filters/Multicouplers Considered Yes
Tx/Rx Systems Excluded None
Maximum Path Distance 50feet
Site File Name SD03XC154.dta
Introduction
In 1996, the FCC adopted new guidelines on evaluating human exposure to RF energy
produced by transmitters licensed and authorized by the FCC. These guidelines were based
on recommended exposure criteria issued by the NCRP and ANSI/IEEE. The exposure criteria
identify threshold levels where harmful biological effects may occur, and the recommended
Maximum Permissible Exposure (MPE) values for both the electrical and magnetic field
strength and the power density as outlined in Table 1. These exposure limits are based on
criteria quantified in terms of specific absorption rate (SAR). Findings show that the whole-
body human absorption of RF energy varies with frequency of the RF signal and therefore the
guidelines are frequency dependent.
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Table 1. FCC Limits for Maximum Permissible Exposure (MPE)
(A) Limits for Occupational/Controlled Exposure
Frequency Electrical Field Electrical Field Power Density
Range Strength (E) Strength (H) (S)
(MHz) (V/m) (Aim) (mW/cm2)
0.3-30 614 1.63 (100)*
3-30 1842/f 4.89/f (900/f2)*
30-300 61.4 0.163 1.0
300-1500 f/300
1500-100,000 5
(B) Limits for General Population/Uncontrolled Exposure
Frequency
Range
(MHz)
0.3-1.34
1.34-30
30-300
300-1500
1500-100,000
f = frequency in MHz
Electrical Field
Strength (E)
(V/m)
614
842/f
27.5
Electrical Field
Strength (H)
(Aim)
1.63
2.19/f
0.073
Power Density
(S)
(mW/cm2}
(100}*
(180/f)*
0.2
f/1500
1
*Plane-wave equivalent power density
SD03XC154
Averaging Time
I E I 2, I H I 2, or S
(minutes)
6
6
6
6
6
Averaging Time
I E 12• I H 12• or S
(minutes)
30
30
30
30
30
The FCC defines two exposure categories: The compliance requirements for each category
are based on a person's awareness and the ability to exercise control over his or her
exposure.
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. These limits 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.
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 can not exercise control over their exposure.
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Figure 1. FCC Limits for Maximum Permissible Exposure (MPE)
Plane wave equivalent Power Density mW/cm2
Methodology
100
10
5
0.2
~-O:Cl.JIBirna!Cnrtrdlffi B<pOSLre
----GalBal Pop.JalorNn:criri:Jied B<postre
\_ ---_/
/
/
/---- ------
/
0.1 ·--------::-':-------'--:'---~---==--..._._--=-=-~~___.
0.03
1.34 1 ,9Il
i3JO,CID
HD,OOO
SD03XC154
This section describes methods and procedures used in evaluating MPE compliance at the site
of interest.
Spatial-peak
The maximum RF energy across the area of the human body (about six (6) ft high) that an
Average
over Area
individual can be exposed to, is considered the Whole Body Peak (WBP). This level should
be considered as the highest level that is found in the area of interest. If during the evaluation
of an area for exposure there are no WBP exposures above the MPE being considered, the
area is considered below the limits and requires no additional evaluation.
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Spatial-averaging
If, during the evaluation of an area for potential exposure, it is determined that there are areas
where peak levels (WBP) will exceed the MPE, then spatial-averaging is required. Spatial-
averaging considers the whole area of the human body in the evaluation of exposure. If there
is an area that has RF fields above the applicable MPE, additional vertical measurements
should be taken to understand the levels between ground level and two (2) meters (about six
(6) ft high). The average of these vertical measurements is the Spatial-averaged exposure,
which is used to determine compliance with the MPE.
Time-averaging
MPE's in the guidelines are in terms of a time-averaged exposure, typically either 6-minute for
Occupational/Controlled MPE or 30-minutes for General Population/Uncontrolled MPE. The
averaging times are used to regulate the energy absorption rate in an individual exposed to RF
fields so that the total energy delivered over the averaging time does not exceed FCC
guidelines. This permits short duration exposure to much higher level fields as long as the
average value over the prescribed time remains within the MPE.
While time averaging is considered an acceptable mechanism for managing high exposure
levels, it requires considerable attention and consideration. There is potential for error and
thus, the use of time averaging alone generally should be avoided. If situations are
encountered where levels exceed the exposure permitted with spatial-averaging, then other
means should be utilized to reduce exposure. There are situations however, where time
averaging may prove to be an acceptable method available to control exposure. One of these
situations is tower climbing. While on a tower, a climber may move through fields that are in
excess of the limits for continuous exposure. If a steady rate of ascent is maintained the time-
weighted averaged exposure can be maintained below the limit allowed in the guidelines.
Exposure Evaluation
Evaluating possible RF exposure levels can be done using both theoretical models and
physical testing. Modeling a site allows the tester to be aware of situations and anticipate
locations where close physical examination is required.
2.0 Site Description
The communication systems located at this site are described in this section as well as the
configuration of the antenna systems.
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The site parameters are:
Site Name: SD03XC 154
Owner:
Site Description: Nextel Colocation with SPCS on Monopalm
Address:
Latitude:
Longitude:
Elevation:
Notes:
2.1 Communications Systems
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The Table below presents a list of the communications systems at the site.
System Provider Technology Frequency Band
1 SPCS PCS CDMA 1710-1990 MHz-PCS
2 SPCS PCSCDMA 1710-1990 MHz-PCS
3 NEXTEL iDEN 806 -896 MHz -Land Mobile
2.2 Antenna Systems
The Table below presents a list of the antenna systems at the site.
Ant Mfg Antenna Model Gain Hgt Orient Sec-Ant Transmission Line Line
# (dBd) (ft) (deg) tor Use Line Type Loss Length
(/100') (tt)
1 EMS AKRR651802 C 15.3 17 90 0 Tx/Rx 1-5/8 in. Foam 0.44 37
3 EMS AKRR651802 C 15.3 17 320 0 Tx/Rx 1-5/8 in. Foam 0.44 37
5 EMS AKFR651300 2 13.3 30 100 1 Tx/Rx 1-5/8 in. Foam 0.41 50
7 EMS AKFR651300 2 13.3 30 200 2 Tx/Rx 1-5/8 in. Foam 0.41 50
9 EMS AKFR651300 2 13.3 30 330 3 Tx/Rx 1-5/8 in. Foam 0.41 50
3.0 Transmitter Frequencies
The Table below presents a list of all transmitter frequencies at the site.
Freq Ant Provider Model Technology Channel Label ID Frequency Power
# # ~tts)
1 1 SPCS Lucent PCSCDMA Chan-25 A 1931.2500 16
2 1 SPCS Lucent PCSCDMA Chan-50 B 1932.5000 16
3 3 SPCS Lucent PCSCDMA Chan-25 E 1931.2500 16
4 3 SPCS Lucent PCSCDMA Chan-50 F 1932.5000 16
5 5 NEXTEL Motorola iDEN Chan-473 I 862.81250 2
6 7 NEXTEL Motorola iDEN Chan-231 J 856.76250 2
7 9 NEXTEL Motorola iDEN Chan-233 K 856.81250 2
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BW
(KHz)
1250
1250
1250
1250
30
30
30
SD03XC154
4.0 Maximum Permissible Emission Analysis
The MPE analysis consists of evaluating the RF transm itter power being emitted from each
active antenna at the communications site. Power density calcu lations are perform ed based
on where a human (observer) would be located at the site. The power density values are then
converted to MPE percentages and each anten na's MPE percentages are summed together to
provide a composite MPE pe rcentage for each observer location. The graph depicts the
exposure level on a 6 foot tall observer, standing at ground level and 50 feet away from
the tower and what the exposure level would be as the distance decreases to the tower.
At no time are the MPE limits exceeded. The composite graph is presented below.
~ IJ.I ~
~
23.0
20.1
18.4
16.1
13.8
11.5
9.2
6.9
4.6
2.3
0.0 '-Hr-H-+t-++-++++++-+-t-H-t-Hr-H++++++++-+-t-t-Hr-Hr-H-+-+++++++i
1 3 5 '7 9 11 13 15 1 '7 19 21 23 25 27 29 31 33 35 3'7 39 41 43 45 4'7 49
2 4 6 8 10 12 14 16 18 20 22 24 26 28 30 32 34 36 38 40 42 44 46 48 50
Distance (ft)
Composite Maximum Permissible Emissions Graph
• Genersl
• Occupational
As shown on the graph , the MPE levels are highest where the antennas are conce ntrated.
Any MPE levels above the 100% Limit Line exceeds the maximum permissible exposure levels
for humans, based on th e MPE Standard selected.
Calcu lati on details fo r each antenna are provided in the following Table. The Max %MPE
column depicts the Maximum Permissible Exposure percentage for that particular antenna.
Provider Ant Ant Ant Frequency Line Filter Tx Tx Pwr Calc'd Ant Max
Nbr Hgt Lgth (MHz) Loss Loss Qty (watts) Ant Gain EIRP %MPE
(feet) (feet) (dB) (dB) (dB) (watts)
SPCS 1 17 7 1931.2500 0.44 5.41 2 16 0 8.31 10.19
SPCS 3 17 7 1931.2500 0.44 5.41 2 16 0 8.31 10.19
NEXTEL 5 30 13 862.8125 0.41 1.7 1 2 0 1.23 0.65
NEXTEL 7 30 13 856.7625 0.41 1.7 1 2 0 1.23 0.66
NEXTEL 9 30 13 856.8125 0.41 1.7 1 2 0 1.23 0.66
In cases where the predicted power density levels exceed MPE limits, alte rin g the location of
the antennas can lead to changing the composite power spectral density and thus bringing the
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SD03XC154
tower/site into compliance. Also, reducing the transmitter output power, if possible, can lead to
lowering the average power density and thus reducing the amount of RF exposure.
Conclusion:
The cumulative or total combined power density of the Sprint and Nextel antennas that the
general public would be exposed to standing at the base of the monopalm is .2235 mw/cm2 ,
which is 22.35% (MPE) or approximately one fourth the value of 1 mW/cm2 established by the
FCC as the maximum permissible exposure (MPE) limit for the general public.
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