RF Exposure Info

FCC ID: H9PMC1790

RF Exposure Info

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FCCID_995489

RF EXPOSURE REPORT REPORT NO.: SA970612H01 MODEL NO.: MC1790 ACCORDING: FCC Guidelines for Human Exposure IEEE C95.1 APPLICANT: Symbol Technologies Inc. ADDRESS: One Symbol Plaza, Holtsville, NY 11742- 1300 U.S.A. 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.: SA970612H01 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.: SA970612H01 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 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.: SA970612H01 3

6. Test Results 6.1 Antenna Gain The maximum gain measured in Fully Anechoic Chamber is 2.04dBi for 2.4GHz or 1.59956 (numeric) The maximum gain measured in Fully Anechoic Chamber is 4.08dBi for 5GHz or 2.558586 (numeric) 6.2 Output Power Into Antenna & RF Exposure value at distance 20cm: For 15.247(2.4GHz) : 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 35.156 0.011 1.0 6 2437 34.435 0.011 1.0 11 2462 31.261 0.010 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 40.832 0.013 1.0 6 2437 77.446 0.025 1.0 11 2462 39.084 0.012 1.0 For 15.247(5GHz) : For Part 802.11a: Channel Limit of Output Power to Power Density Channel Frequency Power Density Antenna (mW) (mW/cm2) (MHz) (mW/cm2) 1 5745 65.313 0.033 1.0 3 5785 79.433 0.040 1.0 5 5825 81.658 0.042 1.0 Report No.: SA970612H01 4

For 15.407(5GHz) : For Part 802.11a: Channel Limit of Output Power to Power Density Channel Frequency Power Density Antenna (mW) (mW/cm2) (MHz) (mW/cm2) 1 5180 16.406 0.008 1.0 2 5200 24.831 0.013 1.0 4 5240 12.735 0.006 1.0 5 5260 18.535 0.009 1.0 7 5300 16.788 0.009 1.0 8 5320 7.870 0.004 1.0 9 5500 10.864 0.006 1.0 14 5600 16.069 0.008 1.0 19 5700 4.808 0.002 1.0 Report No.: SA970612H01 5


Document Created: 2008-08-28 16:40:14
Document Modified: 2008-08-28 16:40:14
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