RF Exposure

FCC ID: H8NWLL3050

RF Exposure Info

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FCCID_497229

FCC ID: H8NWLL3050




                   RF EXPOSURE REPORT

                      REPORT NO.: SA920624R01B
                       MODEL NO.: WLL3050


                      ACCORDING: FCC Guidelines for Human Exposure
                                 IEEE C95.1




                   APPLICANT: ASKEY COMPUTER CORP.

                     ADDRESS: 10F, NO.119, CHIENKANG RD., CHUNG-HO,
                              TAIPEI TAIWAN R.O.C.




                   ISSUED BY:   Advance Data Technology Corporation

               LAB ADDRESS: No. 47, 14th Ling, Chia Pau Tsuen, Lin Kou
                                Hsiang 244, Taipei Hsien, Taiwan, R.O.C.
              TEST LOCATION: No. 19, Hwa Ya 2n d Rd., Wen Hwa Tsuen, Kwei
                             Shan Hsiang, Taoyuan Hsien 333, Taiwan,
                             R.O.C.




Report No.: SA920624R01B               1


FCC ID: H8NWLL3050




          RF Exposure Measurement (Mobile Device)
1. Introduction

2.4GHz frequency band is regarded specially as a dangerous band for its heating
harmfulness to the human body. That’s why microwave oven is operating in this
frequency band. The manufacturer whose product is working in this frequency band is
obligatory to prove the harmfulness of his product.
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), and 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.



2. Classification
The antenna of the product, under normal use condition, is at least 20cm away from the
body of the user. Warning statement for keeping 20cm separation distance and the
prohibition of operating next to a person has been printed on the user’s manual. So, this
product is classified as the Mobile Device.


3. 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).




Report No.: SA920624R01B                      2


FCC ID: H8NWLL3050




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
    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
     30-300            27.5          0.073             0.2                    30
   300-1500               …                 …               F/1500            30
 1500-100,000             …                 …                 1.0             30
F = Frequency in MHz

4. 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 distance r
where the MPE limit is reached.

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

5. EUT Operating condition
The software provided by Manufacturer enabled the EUT to transmit and receive data at
lowest, middle and highest channel individually.




Report No.: SA920624R01B                     3


FCC ID: H8NWLL3050




6. Test Results

6.1 Antenna Gain


The maximum Gain measured in Fully Anechoic Chamber is 1.65dBi or 1.4622 (numeric).

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

 For 2.4GHz band:
               Channel                                                    Limit of
                                  Output Power to Power Density
  Channel     Frequency                                                Power Density
                                   Antenna (mW)     (mW/cm2 )
                 (MHz)                                                   (mW/cm2 )
       1          2412                 47.424               0.014           1.0
       6          2437                 48.195               0.014           1.0
      11          2462                 48.084               0.014           1.0




Report No.: SA920624R01B                      4



Document Created: 2004-12-10 09:51:26
Document Modified: 2004-12-10 09:51:26

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