RF Exposure Info

FCC ID: KA2DIR825A1

RF Exposure Info

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FCCID_979209

FCC ID: KA2DIR825A1 RF EXPOSURE REPORT REPORT NO.: SA970630L13 MODEL NO.: DIR-825 ACCORDING: FCC Guidelines for Human Exposure IEEE C95.1 APPLICANT: D-Link Corporation ADDRESS: 17595 Mt. Herrmann, Fountain Valley, CA 92708, U.S.A. ISSUED BY: Advance Data Technology Corporation LAB ADDRESS: No.47, 14th Ling, Chia Pau Tsuen, Linko Hsiang 244, Taipei Hsien, Taiwan, R.O.C. TEST LOCATION: No. 19, Hwa Ya 2nd Rd, Wen Hwa Tsuen, Kwei Shan Hsiang, Taoyuan Hsien 333, Taiwan, R.O.C. Report No: SA970630L13 1

FCC ID: KA2DIR825A1 RF EXPOSURE MEASUREMENT (MOBILE DEVICE) 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 2 RANGE (MHz) STRENGTH (V/m) STRENGTH (A/m) (mW/cm ) (minutes) (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 30 1500-100,000 … … 1.0 30 F = Frequency in MHz Report No: SA970630L13 2

FCC ID: KA2DIR825A1 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 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 r. 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: SA970630L13 3

FCC ID: KA2DIR825A1 6. TEST RESULTS 6.1 ANTENNA GAIN The maximum Gain measured in Fully Anechoic Chamber is 2dBi or 1.585(numeric). 6.2 OUTPUT POWER INTO ANTENNA & RF EXPOSURE VALUE AT DISTANCE 20cm: For 2.400 ~ 2.4385GHz band: 802.11b DSSS MODULATION: LIMIT OF CHANNEL POWER PEAK POWER PEAK POWER POWER CHANNEL FREQUENCY DENSITY OUTPUT (mW) OUTPUT (dBm) DENSITY (MHz) (mW/CM2) (mW/CM2) 1 2412 89.536 19.52 0.028 1.000 6 2437 89.536 19.52 0.028 1.000 11 2462 90.782 19.58 0.029 1.000 802.11g OFDM MODULATION: LIMIT OF CHANNEL POWER PEAK POWER PEAK POWER POWER CHANNEL FREQUENCY DENSITY OUTPUT (mW) OUTPUT (dBm) DENSITY (MHz) (mW/CM2) (mW/CM2) 1 2412 90.991 19.59 0.029 1.000 6 2437 102.094 20.09 0.032 1.000 11 2462 89.743 19.53 0.028 1.000 DRAFT 802.11n (20MHz) OFDM MODULATION: PEAK POWER OUTPUT TOTAL TOTAL LIMIT OF CHAN. POWER (dBm) PEAK PEAK POWER CHAN. FREQ. DENSITY POWER POWER DENSITY (mW/CM2) (MHz) (mW/CM2) CHAIN 0 CHAIN 1 (mW) (dBm) 1 2412 15.52 15.53 71.372 18.54 0.023 1.000 6 2437 17.60 17.50 113.778 20.56 0.036 1.000 11 2462 14.56 14.56 57.152 17.57 0.018 1.000 Report No: SA970630L13 4

FCC ID: KA2DIR825A1 DRAFT 802.11n (40MHz) OFDM MODULATION: PEAK POWER OUTPUT TOTAL TOTAL LIMIT OF CHAN. POWER (dBm) PEAK PEAK POWER CHAN. FREQ. DENSITY POWER POWER DENSITY (mW/CM2) (MHz) (mW/CM2) CHAIN 0 CHAIN 1 (mW) (dBm) 1 2422 12.51 11.59 32.245 15.08 0.010 1.000 4 2437 16.04 15.56 76.154 18.82 0.024 1.000 7 2452 12.08 11.53 30.367 14.82 0.010 1.000 For 5.150 ~ 5.250GHz band: 802.11a OFDM MODULATION: LIMIT OF CHANNEL POWER PEAK POWER PEAK POWER POWER CHANNEL FREQUENCY DENSITY OUTPUT (mW) OUTPUT (dBm) DENSITY (MHz) (mW/CM2) (mW/CM2) 36 5180 16.032 12.05 0.005 1.000 40 5200 16.181 12.09 0.005 1.000 48 5240 15.996 12.04 0.005 1.000 DRAFT 802.11n (20MHz) OFDM MODULATION: PEAK POWER OUTPUT TOTAL TOTAL LIMIT OF CHAN. POWER (dBm) PEAK PEAK POWER CHAN. FREQ. DENSITY POWER POWER DENSITY (mW/CM2) (MHz) (mW/CM2) CHAIN 0 CHAIN 1 (mW) (dBm) 36 5180 9.56 8.53 16.165 12.09 0.005 1.000 40 5200 12.09 12.10 32.399 15.11 0.010 1.000 48 5240 12.04 12.02 31.918 15.04 0.010 1.000 DRAFT 802.11n (40MHz) OFDM MODULATION: PEAK POWER OUTPUT TOTAL TOTAL LIMIT OF CHAN. POWER (dBm) PEAK PEAK POWER CHAN. FREQ. DENSITY POWER POWER DENSITY (mW/CM2) (MHz) (mW/CM2) CHAIN 0 CHAIN 1 (mW) (dBm) 38 5190 9.57 9.64 18.262 12.62 0.006 1.000 46 5230 11.55 11.61 28.777 14.59 0.009 1.000 Report No: SA970630L13 5

FCC ID: KA2DIR825A1 For 5.725 ~ 5.850GHz band: 802.11a OFDM MODULATION: LIMIT OF CHANNEL POWER PEAK POWER PEAK POWER POWER CHANNEL FREQUENCY DENSITY OUTPUT (mW) OUTPUT (dBm) DENSITY (MHz) (mW/CM2) (mW/CM2) 149 5745 50.816 17.06 0.016 1.000 157 5785 51.050 17.08 0.016 1.000 165 5825 56.754 17.54 0.018 1.000 DRAFT 802.11n (20MHz) OFDM MODULATION: PEAK POWER OUTPUT TOTAL TOTAL LIMIT OF CHAN. POWER (dBm) PEAK PEAK POWER CHAN. FREQ. DENSITY POWER POWER DENSITY (mW/CM2) (MHz) (mW/CM2) CHAIN 0 CHAIN 1 (mW) (dBm) 149 5745 16.60 16.07 86.166 19.35 0.027 1.000 157 5785 16.63 16.13 87.046 19.40 0.027 1.000 165 5825 12.52 12.07 33.971 15.31 0.011 1.000 DRAFT 802.11n (40MHz) OFDM MODULATION: PEAK POWER OUTPUT TOTAL TOTAL LIMIT OF CHAN. POWER (dBm) PEAK PEAK POWER CHAN. FREQ. DENSITY POWER POWER DENSITY (mW/CM2) (MHz) (mW/CM2) CHAIN 0 CHAIN 1 (mW) (dBm) 151 5755 15.56 15.05 67.964 18.32 0.021 1.000 159 5795 15.50 15.02 67.250 18.28 0.021 1.000 CONCULSION: Both of the modules can transmit simultaneously, the formula of calculated the MPE is: CPD1 / LPD1 + CPD2 / LPD2 + ……etc. < 1 CPD = Calculation power density LPD = Limit of power density WLAN 2.4G + WLAN 5.0G = 0.036 + 0.027 = 0.063 Therefore, the maximum calculation of this situation is 0.063, which is less than the “1” limit. Report No: SA970630L13 6


Document Created: 2008-07-31 14:01:34
Document Modified: 2008-07-31 14:01:34
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