RF Exposure Info

FCC ID: Q9DRAP2WG

RF Exposure Info

Download: PDF
FCCID_1069796

                     RF EXPOSURE REPORT

               REPORT NO.: SA960522H09D
                MODEL NO.: SMCWBR11-G, WA2121, RAP-2WG


               ACCORDING: FCC Guidelines for Human Exposure
                          IEEE C95.1


                 APPLICANT:   Aruba Networks, Inc.

                   ADDRESS:   1322 Crossman Avenue , Sunnyvale, CA 94089




                 ISSUED BY:   Bureau Veritas Consumer Products Services (H.K.)
                              Ltd., Taoyuan Branch
            LAB LOCATION:     No. 81-1, Lu Liao Keng, 9th Ling,Wu Lung Tsuen,
                              Chiung Lin Hsiang, Hsin Chu Hsien 307, Taiwan




Report No.: SA960522H09D                 1

Reference No.:971113H01


                          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 our lab, 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.: SA960522H09D                     2

Reference No.:971113H01


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 Manufacturer enabled the EUT to transmit and receive data at
lowest, middle and highest channel 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.: SA960522H09D                     3

Reference No.:971113H01


6. Test Results
6.1 Antenna Gain

  The maximum Gain measured in Fully Anechoic Chamber is 1.5dBi or 1.412538
  (numeric)

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

 For Part 802.11b:
                   Channel                                         Limit of
                              Output Power to   Power Density
   Channel        Frequency                                     Power Density
                              Antenna (mW)        (mW/cm2)
                    (MHz)                                         (mW/cm2)
      1              2412         60.674           0.017             1.0
      6              2437         51.761           0.015             1.0
      11             2462         54.954           0.015             1.0

 For Part 802.11g:
                   Channel                                         Limit of
                              Output Power to   Power Density
   Channel        Frequency                                     Power Density
                              Antenna (mW)        (mW/cm2)
                    (MHz)                                         (mW/cm2)
      1              2412         57.016           0.016             1.0
      6              2437        108.143           0.030             1.0
      11             2462         51.523           0.014             1.0




Report No.: SA960522H09D                4

Reference No.:971113H01



Document Created: 2009-01-20 13:35:13
Document Modified: 2009-01-20 13:35:13

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