RF Exposure

FCC ID: LDK102089P

RF Exposure Info

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FCCID_2858357

EDCS-1529839




                   RF Exposure Study - Engineering Analysis per

                                   FCC 2.1091

                           Industry Canada RSS-102


                             AIR-CAP1532E-B-K9
                                 FCC ID: LDK102089P




    Prepared By:   Cisco Systems Inc
                   170 West Tasman
                   San Jose, CA 95134
                   USA


EDCS-1529839

1.0: Attestation Statement of Compliance

The Cisco AIR-CAP1532E-B-K9, 802.11N radio has been evaluated for Maximum Permissible
Exposure in compliance with 47 Code of Federal Regulations 2.1093. The evaluation was in
accordance with methodology as referenced in FCC Bulletin OET 65C (rev 01-01). This report
serves as the additional technical analysis of the Cisco radio modules

This study addresses the addition of an additional pair of transmitters using the data derived in the
afore mentioned report #
2.4GHz DTS 13dBi report EDCS#- 1324627
5GHz 14dBi UNII-1 report EDCS-1518109
5GHz 14dBi UNII-2 report EDCS-1324630
5GHz 14dBi UNII-2ext reports EDCS-1518110
5GHz 14dBi UNII-3 report EDCS-1518111

The limits used for this evaluation are in line with the recommendations of the World Health
Organizations (WHO) International Committee on Non Ionizing Radiation Protection (ICNIRP) as
well as the American National Standards Institute (ANSI) C95.1.

The limits chosen are of General Population/Uncontrolled Exposure.

This analysis also complies with the requirements stated in Industry Canada RSS-102 as well as the
applicable Australian and New Zealand regulations.

the following case scenarios were used :
2.4GHz WLAN
5GHz WLAN

This device must be installed to provide a separation distance of at least 40 cm from all
persons. Installers must be provided with antenna installation and transmitter operating conditions
for satisfying RF exposure compliance.

Based on the study this case scenario, the General Population/Uncontrolled Exposure and the
minimum recommended distance is around 40cm (16 inches) from the antenna.




Jose Aguirre
Cisco Systems Inc
Corporate Compliance and Certifications
125 West Tasman Drive
San Jose, CA 95134
Email: joaguirr@cisco.com


EDCS-1529839



2.0 EUT Description.
The AIR-CAP1532E-B-K9 Cisco 802.11N Radio support the following modes of operation. The modes are further defined
in the radio Theory of Operation. The modes included in this report represent the worst-case data for all modes.

         802.11n - Non HT-20, One Antenna, 6 to 54 Mbps
         802.11n - Non HT-20, Two Antennas, 6 to 54 Mbps

         802.11n - HT-20, One Antenna, M0 to M7
         802.11n - HT-20, Two Antennas, M0 to M7
         802.11n - HT-20, Two Antennas, M8 to M15

         802.11n - HT-20 Beam Forming, Two Antennas, M0 to M7
         802.11n - HT-20 Beam Forming, Two Antennas, M8 to M15

         802.11n - HT-20 STBC, Two Antennas, M0 to M7

         802.11n - Non HT-40 Duplicate, One Antenna, 6 to 54 Mbps
         802.11n - Non HT-40 Duplicate, Two Antennas, 6 to 54 Mbps

         802.11n - HT-40, One Antenna, M0 to M7
         802.11n - HT-40, Two Antennas, M0 to M7
         802.11n - HT-40, Two Antennas, M8 to M15

         802.11n - HT-40 Beam Forming, Two Antennas, M0 to M7
         802.11n - HT-40 Beam Forming, Two Antennas, M8 to M15

         802.11n - HT-40 STBC, Two Antennas, M0 to M7

The following antennas are supported by this product series.
The data included in this report represent the worst case data for all antennas.

                                                                                             >30 degree 5 GHz
                                                                              Antenna Gain     Antenna Gain
 Frequency         Part Number                  Antenna Type                      (dBi)            (dBi)
                 AIR-ANT5180V-N                Single Band Omni                     8               -3
   5 GHz               AIR-                 Single Band, Directional                                 5
                 ANT5114P2M-N                        Patch                         14
                  AIR-ANT2547V-                                                                     -6
                        N=                      Dual-band Omni                     4/7
                 AIR-ANT2547VG-                                                                     -6
 2.4/5 GHz
                        N=                  Dual-band Omni, Gray                   4/7
                       AIR-                Dual-band/Dual Polarized                                  1
                 ANT2588P3M-N=                Directional, Patch                   8/8


EDCS-1529839


3.0     Methodology

All calculations were made in accordance with ANSI C95.1, and FCC OET 65C.


4.0     Technical Requirements


          4.1     Single Band Operation – Limits


FCC Limits for Maximum Permissible Exposure (MPE)
(A) Limits for Occupational/Controlled Exposure


      Frequency           Electric Field      Magnetic Field         Power Density       Averaging Time
        Range             Strength (E)        Strength (H)               (S)              |E|2, |H|2 or S
        (MHz)                (V/m)                (A/m)                (mW/cm2)             (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 Exposure


      Frequency           Electric Field      Magnetic Field         Power Density       Averaging Time
        Range             Strength (E)        Strength (H)               (S)              |E|2, |H|2 or S
        (MHz)                (V/m)                (A/m)                (mW/cm2)             (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

NOTE 1: See Section 1 for discussion of exposure categories.

NOTE 2: The averaging time for General Population/Uncontrolled exposure to fixed transmitters is not applicable for
         mobile and portable transmitters. See 47 CFR §§2.1091 and 2.1093 on source-based time-averaging
         requirements for mobile and portable transmitters.


EDCS-1529839


5.0     Calculations

      Given
                   E=√(30*P*G)/d and     S=E^2/3770
      where
                   E=Field Strength in Volts/meter
                   P=Power in Watts
                   G=Numeric Antenna Gain
                   d=Distance in meters
                   S=Power Density in mW/cm^2

      Combine equations and rearrange the terms to express the distance as a function of the remaining
      variables:
                 d=√((30*P*G)/(3770*S))

      Changing to units of power in mW and distance in cm, using:
                  P(mW)=P(W)/1000       d(cm)=100*d(m)
      yields
                  d=100*√((30*(P/1000)*G)/(3770*S))
                  d=0.282*√(P*G/S)
      where
                  d=Distance in cm
                  P=Power in mW
                  G=Numeric Antenna Gain
                  S=Power Density in mW/cm^2

      Substituting the logarithmic form of power and gain using:
                    P(mW)=10^(P(dBm)/10)         G(numeric)=10^(G(dBi)/10)
      yields
                    d=0.282*10^((P+G)/20)/√S                     Equation (1)
      and
                    s=((0.282*10^((P+G)/20))/d)^2                Equation (2)
      where
                    d=MPE distance in cm
                    P=Power in dBm
                    G=Antenna Gain in dBi
                    S=Power Density in mW/cm^2


EDCS-1529839


6.0   Results

         Equation (1) and the measured peak power are used to calculate the MPE distance. Note that for mobile or
         fixed location transmitters such as an access point, the minimum separation distance is 40 cm even if the
         calculations indicate that the MPE distance may be less.

         S=1mW/cm^2 maximum. The highest supported antenna gain is 6 dBi (9dBi with beamforming). Using the
         peak power levels recorded in the test report along with Equation 1 above, the MPE distances are calculated as
         follows.

MPE Calculations:
                                                 Peak
                           Power               Transmit          Antenna            MPE
                           Density              Power             Gain             Distance       Limit       Margin
     Band                (mW/cm^2)              (dBm)             (dBi)             (cm)          (cm)         (cm)
  2.4GHz DTS                 1                   26.9              13               27.88          40         12.12
 5GHz UNII-1                 1                   20.9              14               15.68          40         24.32
 5GHz UNII-2                 1                   12.4              14               5.89           40         34.11
 5GHz UNII-2e                1                   13.7              14               6.84           40         33.16
 5GHz UNII-3                 1                   25.2              14               25.72          40         14.28

To maintain compliance, installations will assure a separation distance of at least 40cm.

Using Equation 2, the MPE levels (s) at 40 cm are calculated as follows:

                                      Peak
                     MPE            Transmit        Antenna           Power
                    Distance         Power           Gain             Density             Limit             Margin
    Band             (cm)            (dBm)           (dBi)          (mW/cm^2)           (mW/cm^2)         (mW/cm^2)
 2.4GHz DTS            40             26.9            13               0.49                 1                0.51
5GHz UNII-1            40             20.9            14               0.15                 1                0.85
5GHz UNII-2            40             12.4            14               0.02                 1                0.98
5GHz UNII-2e           40             13.7            14               0.03                 1                0.97
5GHz UNII-3            40             25.2            14               0.41                 1                0.59

Calculations with additional transmitters

The AIR-CAP1532E-B-K9 Cisco 802.11N Radio support operation with 2.4GHz WLAN & 5GHz WLAN.

Scenerio 1 :
2.4GHz WLAN ( Highest power)
5GHz WLAN (Highest power)

 TX1 + TX6 = % of standard
 ( 0.49) + (0.41 ) = 0.90

 D (estimate) = 40* %

D = 37.95cm which is less than 40cm recommended

The configuration above co-location calculation is for General Population/Uncontrolled exposure. The minimum
distance recommended is 20cm (8 inches) when all antennas are within 20cm of each other.


EDCS-1529839



References

American National Standards Institute (ANSI), "Safety Levels with Respect to Human Exposure to Radio Frequency Electromagnetic Fields, 3 kHz to 300
GHz," ANSI/IEEE C95.1-1992 (previously issued as IEEE C95.1-1991). Copyright 1992 by the Institute of Electrical and Electronics Engineers, Inc. (IEEE),
New York, N.Y. 10017. For copies contact the IEEE: 1-800-678-4333 or 1-908-981-1393.
American National Standards Institute (ANSI), "Recommended Practice for the Measurement of Potentially Hazardous Electromagnetic Fields - RF and
Microwave”. ANSI/IEEE C95.3-1992. Copyright 1992, The Institute of Electrical and Electronics Engineers, Inc. (IEEE), New York, NY 10017. For copies
contact the IEEE: 1-800-678-4333 or 1-908-981-1393.



FCC OET 65C Evaluating Compliance with FCC Guidelines for Human Exposure to RF Fields from 9KHz to 40 Ghz



Document Created: 2017-08-27 00:49:21
Document Modified: 2017-08-27 00:49:21

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