RF Exposure

FCC ID: LDK102098

RF Exposure Info

Download: PDF
FCCID_3378093

EDCS- 11523117




                   RF Exposure Study - Engineering Analysis per

                                   FCC 2.1091



                            AIR-AP1832I-x-K9
                                    (x=B,S,T)
                               FCC ID: LDK102098




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


EDCS- 11523117

1.0: Attestation Statement of Compliance

The Cisco AIR-AP1832I-B-K9, 802.11AC radio has been evaluated for Maximum Permissible
Exposure in compliance with 47 Code of Federal Regulations 2.1091. The evaluation was in
accordance with methodology as referenced in FCC Bulletin OET 65C (rev 01-01) along with KDB
447498 D01 General RF Exposure Guidance. 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 report
5GHz UNII-1 report
5GHz UNII-2 report
5GHz UNII-2ext reports
5GHz UNII-3 report

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.


the following case scenarios were used :
2.4GHz WLAN ( Highest power)
5GHz WLAN ( Highest power)

This device must be installed to provide a separation distance of at least 20 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 20cm (8 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- 11523117


2.0 EUT Description.

The Cisco Aironet 802.11ac Radio supports 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.


        2.4GHz Radio
        802.11n/ac - Legacy CCK, One Antenna, 1 to 11 Mbps
        802.11n/ac - Legacy CCK, Two Antennas, 1 to 11 Mbps
        802.11n/ac - Legacy CCK, Three Antennas, 1 to 11 Mbps

        802.11n/ac - Non HT20, One Antenna, 6 to 54 Mbps, 1ss
        802.11n/ac - Non HT20, Two Antennas, 6 to 54 Mbps, 1ss
        802.11n/ac - Non HT20, Three Antennas, 6 to 54 Mbps, 1ss

        802.11n/ac - Non HT20 Beam Forming, Two Antennas, 6 to 54 Mbps, 1ss
        802.11n/ac - Non HT20 Beam Forming, Three Antennas, 6 to 54 Mbps, 1ss

        802.11n/ac - HT/VHT20, One Antenna, M0 to M7, 1ss
        802.11n/ac - HT/VHT20, Two Antennas, M0 to M7, 1ss
        802.11n/ac - HT/VHT20, Two Antennas, M8 to M15, 2ss
        802.11n/ac - HT/VHT20, Three Antennas, M0 to M7, 1ss
        802.11n/ac - HT/VHT20, Three Antennas, M8 to M15, 2ss

        802.11n/ac - HT/VHT20 Beam Forming, Two Antennas, M0 to M7, 1ss
        802.11n/ac - HT/VHT20 Beam Forming, Two Antennas, M8 to M15, 2ss
        802.11n/ac - HT/VHT20 Beam Forming, Three Antennas, M0 to M7, 1ss
        802.11n/ac - HT/VHT20 Beam Forming, Three Antennas, M8 to M15, 2ss

        802.11n/ac - HT/VHT20 STBC, Two Antennas, M0 to M7, 2ss
        802.11n/ac - HT/VHT20 STBC, Three Antennas, M0 to M7, 2ss

        5GHz Radio
        802.11n/ac - Non HT20, One Antenna, 6 to 54 Mbps, 1ss
        802.11n/ac - Non HT20, Two Antennas, 6 to 54 Mbps, 1ss
        802.11n/ac - Non HT20, Three Antennas, 6 to 54 Mbps, 1ss

        802.11n/ac - Non HT20 Beam Forming, Two Antennas, 6 to 54 Mbps, 1ss
        802.11n/ac - Non HT20 Beam Forming, Three Antennas, 6 to 54 Mbps, 1ss

        802.11n/ac - HT/VHT20, One Antenna, M0 to M7, 1ss
        802.11n/ac - HT/VHT20, Two Antennas, M0 to M7, 1ss
        802.11n/ac - HT/VHT20, Two Antennas, M8 to M15, 2ss
        802.11n/ac - HT/VHT20, Three Antennas, M0 to M7, 1ss
        802.11n/ac - HT/VHT20, Three Antennas, M8 to M15, 2ss

        802.11n/ac - HT/VHT20 Beam Forming, Two Antennas, M0 to M7, 1ss
        802.11n/ac - HT/VHT20 Beam Forming, Two Antennas, M8 to M15, 2ss
        802.11n/ac - HT/VHT20 Beam Forming, Three Antennas, M0 to M7, 1ss
        802.11n/ac - HT/VHT20 Beam Forming, Three Antennas, M8 to M15, 2ss

        802.11n/ac - HT/VHT20 STBC, Two Antennas, M0 to M7, 2ss
        802.11n/ac - HT/VHT20 STBC, Three Antennas, M0 to M7, 2ss

        802.11n/ac - Non HT40 Duplicate, One Antenna, 6 to 54 Mbps, 1ss
        802.11n/ac - Non HT40 Duplicate, Two Antennas, 6 to 54 Mbps, 1ss
        802.11n/ac - Non HT40 Duplicate, Three Antennas, 6 to 54 Mbps, 1ss

        802.11n/ac - HT/VHT40, One Antenna, M0 to M7, 1ss
        802.11n/ac - HT/VHT40, Two Antennas, M0 to M7, 1ss
        802.11n/ac - HT/VHT40, Two Antennas, M8 to M15, 2ss


EDCS- 11523117

         802.11n/ac - HT/VHT40, Three Antennas, M0 to M7, 1ss
         802.11n/ac - HT/VHT40, Three Antennas, M8 to M15, 2ss

         802.11n/ac - HT/VHT40 Beam Forming, Two Antennas, M0 to M7, 1ss
         802.11n/ac - HT/VHT40 Beam Forming, Two Antennas, M8 to M15, 2ss
         802.11n/ac - HT/VHT40 Beam Forming, Three Antennas, M0 to M7, 1ss
         802.11n/ac - HT/VHT40 Beam Forming, Three Antennas, M8 to M15, 2ss

         802.11n/ac - HT/VHT40 STBC, Two Antennas, M0 to M7, 2ss
         802.11n/ac - HT/VHT40 STBC, Three Antennas, M0 to M7, 2ss

         802.11n/ac - Non HT80 Duplicate, One Antenna, 6 to 54 Mbps, 1ss
         802.11n/ac - Non HT80 Duplicate, Two Antennas, 6 to 54 Mbps, 1ss
         802.11n/ac - Non HT80 Duplicate, Three Antennas, 6 to 54 Mbps, 1ss

         802.11ac - VHT80, One Antenna, M0 to M9 1ss
         802.11ac - VHT80, Two Antennas, M0 to M9 1ss
         802.11ac - VHT80, Two Antennas, M0 to M9 2ss
         802.11ac - VHT80, Three Antennas, M0 to M9 1ss
         802.11ac - VHT80, Three Antennas, M0 to M9 2ss


         802.11ac - VHT80 Beam Forming, Two Antennas, M0 to M9 1ss
         802.11ac - VHT80 Beam Forming, Two Antennas, M0 to M9 2ss
         802.11ac - VHT80 Beam Forming, Three Antennas, M0 to M9 1ss
         802.11ac - VHT80 Beam Forming, Three Antennas, M0 to M9 2ss

         802.11ac - VHT80 STBC, Two Antennas, M0 to M9 2ss
         802.11ac - VHT80 STBC, Three Antennas, M0 to M9 2ss

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

                                                                                   Antenna Gain
     Frequency                  Part Number              Antenna Type
                                                                                       (dBi)
     2.4 / 5 GHz                 3x3 Internal                  Omni                    3/5


EDCS- 11523117


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- 11523117


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- 11523117


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 20 cm even if the
         calculations indicate that the MPE distance may be less.

         S=1mW/cm^2 maximum. The highest supported antenna gain is 5dBi (10dBi with beam forming). 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/cm2)             (dBm)               (dBi)*           (cm)            (cm)       (cm)
    2.4GHz DTS                  1                    22.5              8              9.45            20        10.55
   5GHz UNII-1                  1                    22.6             10              12.03           20        7.97
   5GHz UNII-2                  1                    22.8              7              8.71            20        11.29
   5GHz UNII-2e                 1                    19.7             10              8.61            20        11.39
   5GHz UNII-3                  1                    21.3             10              10.36           20        9.64
*Correlated Gain

To maintain compliance, installations will assure a separation distance of at least 20cm.

Using Equation 2, the MPE levels (s) at 20 cm are calculated as follows:

                                             Peak
                             MPE           Transmit         Antenna          Power
                            Distance        Power             Gain          Density             Limit         Margin
         Band                (cm)           (dBm)            (dBi)*        (mW/cm2)           (mW/cm2)       (mW/cm2)
     2.4GHz DTS                 20            22.5            8              0.22                1             0.78
     5GHz UNII-1                20            22.6            10             0.36                1             0.64
     5GHz UNII-2                20            22.8            7              0.19                1             0.81
    5GHz UNII-2e                20            19.7            10             0.19                1             0.81
     5GHz UNII-3                20            21.3            10             0.27                1             0.73
*Correlated Gain


EDCS- 11523117

Calculations with additional transmitters

The AIR-AP1832I-B-K9 Cisco 802.11AC Radio support operation with 2.4GHz WLAN & 5GHz WLAN.

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

 TX1 + TX2 = % of standard
 ( 0.22) + (0.36) = 0.58

 D (estimate) = 20* %

D = 15.2cm which is less than 20cm 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- 11523117



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: 2019-10-28 14:20:47
Document Modified: 2019-10-28 14:20:47

© 2024 FCC.report
This site is not affiliated with or endorsed by the FCC