RF Exposure Calculation

FCC ID: H8NRTA300W

RF Exposure Info

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FCCID_270972

Industrial Technology Research Institute FCC ID ：H8N-RTA300W Electronics Research & Service Organization Report No. ：510-9107-034F Bldg. 17, 195-4 Sec. 4, Chung Hsing Rd., Chutung,Hsinchu, 310 Taiwan,Republic Of China Page 39 of 43 TEL : 886-3-5917069 FAX : 886-3-5825720 9. RF EXPOSURE EVALUATION According to FCC 1.1310 : The criteria listed in the following table shall be used to evaluate the environment impact of human exposure to radio frequency (RF) radiation as specified in 1.1307(b) LIMITS FOR MAXIMUM PERMISSIBLE EXPOSURE (MPE) Frequency Range Electric Field Magnetic Field Power Density Average Time (MHz) Strength (V/m) Strength (A/m) (mW/cm2) (A) Limits for Occupational / Control Exposures 300-1,500 -- -- F/300 6 1,500-100,000 -- -- 5 6 (B) Limits for General Population / Uncontrol Exposures 300-1,500 -- -- F/1500 6 1,500-100,000 -- -- 1 30 9.1 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 id 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. 9.2 EUT OPERATING CONDITION A software provided by client enabled the EUT to transmit and receive data at lowest, middle and highest channel individually.

Industrial Technology Research Institute FCC ID ：H8N-RTA300W Electronics Research & Service Organization Report No. ：510-9107-034F Bldg. 17, 195-4 Sec. 4, Chung Hsing Rd., Chutung,Hsinchu, 310 Taiwan,Republic Of China Page 40 of 43 TEL : 886-3-5917069 FAX : 886-3-5825720 9.3 TEST RESULT OF RF EXPOSURE EVALUATION Product ： Wireless ADSL Router Test Item ： RF Exposure Evaluation Data Test Mode ： Normal Operation 9.3.1 ANTENNA GAIN Antenna Gain：The maximum Gain measured in fully anechoic chamber is 2dBi linear scale. 9.3.2 OUTPUT POWER INTO ANTENNA & RF EXPOSURE EVALUATION DISTANCE Output Power to Antenna Minimum Allowable Channel Channel Frequency (MHz) (dBm) Distance  From Skin(cm) CH1 2412.00 16.5 2.373532 CH6 2437.00 16.4 2.346362 CH11 2462.00 16.5 2.401016 The distance r (4th column) calculated from the Friis transmission formula is far shorter than 20cm separation requirement. So, RF exposure limit warning or SAR test are not required.


Document Created: 2002-09-15 22:19:15
Document Modified: 2002-09-15 22:19:15
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