RF Exposure revised

FCC ID: UDX-MERAKI-OTDR

RF Exposure Info

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FCCID_855561

                      RF EXPOSURE REPORT

                 REPORT NO.: SA960705H04
                  MODEL NO.: Meraki Outdoor
                     FCC ID: UDX-MERAKI-OTDR


                 ACCORDING: FCC Guidelines for Human Exposure
                            IEEE C95.1


                   APPLICANT: Meraki Networks, Inc.

                     ADDRESS: 313 West Evelyn Ave. Mountain View, CA 94041




                   ISSUED BY: Advance Data Technology Corporation

              LAB LOCATION: No. 81-1, Lu Liao Keng, 9 Ling, Wu Lung Tsuen,
                            Chiung Lin Hsiang, Hsin Chu Hsien,
                            Taiwan, R.O.C.




Report No.: SA960705H04                  1


                          RF Exposure Measurement
1. Introduction

In this document, we try to prove the safety of radiation harmfulness to the human body
for our product. The limit for Maximum Permissible Exposure (MPE) specified in FCC
1.1310 is followed. The Gain of the antenna used in this product is measured in a Fully
Anechoic Chamber (FAC) calibrated for antenna measurement in ADT, and also the
maximum total power input to the antenna is measured. Through the Friis transmission
formula and the maximum gain of the antenna, we can calculate the distance, away from
the product, where the limit of MPE is reached.
Although the Friis transmission formula is a far field assumption, the calculated result of
that is an over-prediction for near field power density. We will take that as the worst case
to specify the safety range.

2. RF Exposure Limit
According to FCC 1.1310: The criteria listed in the following table shall be used to
evaluate the environmental impact of human exposure to radio-frequency (RF) radiation
as specified in 1.1307(b)

LIMITS FOR MAXIMUM PERMISSIBLE EXPOSURE (MPE)

   Frequency         Electric Field   Magnetic Field   Power Density      Average Time
     Range          Strength (V/m)    Strength (A/m)     (mW/cm2)           (minutes)
     (MHz)
                   (A)Limits For Occupational / Control Exposures
    300-1500              …                 …               F/300               6
 1500-100,000             …                 …                 5                 6
             (B)Limits For General Population / Uncontrolled Exposure
    300-1500              …                 …              F/1500               6
 1500-100,000             …                 …                1.0                30
F = Frequency in MHz




Report No.: SA960705H04                      2


3. Friis Formula


Friis transmission formula : Pd = (Pout*G) / (4*pi*r2)


where
Pd = power density in mW/cm2
Pout = output power to antenna in mW
G = gain of antenna in linear scale
Pi = 3.1416
R = distance between observation point and center of the radiator in cm


Pd is the limit of MPE, 1 mW/cm2. If we know the maximum Gain of the antenna and the
total power input to the antenna, through the calculation, we will know the MPE value at
distance 20cm.

Ref. : David K. Cheng, Field and Wave Electromagnetics, Second Edition,
      Page 640, Eq. (11-133).



4. EUT Operating condition
The software provided by client enabled the EUT to transmit and receive data at specific
channel frequencies individually.




5. Classification
The antenna of this product, under normal use condition, is at least 20cm away from the
body of the user. Warning statement to the user for keeping at least 20cm or more
separation distance with the antenna should be included in users manual. So, this device
is classified as Mobile Device




Report No.: SA960705H04                       3


6. Test Results

6.1 Antenna Gain
The antennas used in this product are as following:

                                  Gain Cable lose Net Gain
    No.           Model No.                                         Antenna Type       Connector
                                  (dBi)  (dB)      (dBi)
     1        RFANT5220110A0T          2         0           2           Chip              NA
                                                                   Omni-Directional
     2    ODU-OA-24-0201-A-W       2         0           2                            RP SMA Plug
                                                                      (Dipole)
                                                                   Omni-Directional
     3        ODU-OA-24-0701-A     7         0           7                            RP SMA Plug
                                                                      (Dipole)
                                                                     Directional
     4        ODU-DA-24-0904-A2    9        1.5          7.5                          RP SMA Jack
                                                                      (Panel)

6.2 Output Power Into Antenna & RF Exposure value at distance 20cm:

 For Part 802.11b:

 Antenna 1 :
                      Channel                                                            Limit of
                                       Output Power to           Power Density
   Channel           Frequency                                                        Power Density
                                       Antenna (mW)                (mW/cm2)
                       (MHz)                                                            (mW/cm2)
         1              2412               157.036                   0.050                 1.0
         6              2437                81.658                   0.026                 1.0
         11             2462                52.845                   0.017                 1.0

 Antenna 2 :
                      Channel                                                            Limit of
                                       Output Power to           Power Density
   Channel           Frequency                                                        Power Density
                                       Antenna (mW)                (mW/cm2)
                       (MHz)                                                            (mW/cm2)
         1              2412               164.059                   0.052                 1.0
         6              2437               193.642                   0.061                 1.0
         11             2462               129.420                   0.041                 1.0

 Antenna 3 :
                      Channel                                                            Limit of
                                       Output Power to           Power Density
   Channel           Frequency                                                        Power Density
                                       Antenna (mW)                (mW/cm2)
                       (MHz)                                                            (mW/cm2)
         1              2412               164.059                   0.164                 1.0
         6              2437               193.642                   0.193                 1.0
         11             2462               190.108                   0.190                 1.0




Report No.: SA960705H04                              4


 Antenna 4 :
                  Channel                                         Limit of
                             Output Power to   Power Density
   Channel       Frequency                                     Power Density
                             Antenna (mW)        (mW/cm2)
                   (MHz)                                         (mW/cm2)
      1             2412        146.218           0.164             1.0
      6             2437        193.642           0.217             1.0
      11            2462        112.980           0.126             1.0


 For Part 802.11g:

 Antenna 1 :
                  Channel                                         Limit of
                             Output Power to   Power Density
   Channel       Frequency                                     Power Density
                             Antenna (mW)        (mW/cm2)
                   (MHz)                                         (mW/cm2)
      1             2412        154.525           0.049             1.0
      6             2437        248.886           0.078             1.0
      11            2462        111.173           0.035             1.0

 Antenna 2 :
                  Channel                                         Limit of
                             Output Power to   Power Density
   Channel       Frequency                                     Power Density
                             Antenna (mW)        (mW/cm2)
                   (MHz)                                         (mW/cm2)
      1             2412         95.940           0.030             1.0
      6             2437        174.985           0.055             1.0
      11            2462         99.083           0.031             1.0

 Antenna 3 :
                  Channel                                         Limit of
                             Output Power to   Power Density
   Channel       Frequency                                     Power Density
                             Antenna (mW)        (mW/cm2)
                   (MHz)                                         (mW/cm2)
      1             2412         95.060           0.095             1.0
      6             2437        174.985           0.174             1.0
      11            2462         88.105           0.088             1.0

 Antenna 4 :
                  Channel                                         Limit of
                             Output Power to   Power Density
   Channel       Frequency                                     Power Density
                             Antenna (mW)        (mW/cm2)
                   (MHz)                                         (mW/cm2)
      1             2412         67.764           0.076             1.0
      6             2437        174.985           0.196             1.0
      11            2462         60.534           0.068             1.0




Report No.: SA960705H04                5



Document Created: 2007-10-04 15:52:32
Document Modified: 2007-10-04 15:52:32

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