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求教大神FCC RF MPE评估的两套公式是否完全等价?但是把它们变形后发现结果相差1个数量级啊,还请大神能够帮忙看看,谢谢。A)E= √(30xPxG)/d and S=E2/377
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--> E= (30xPxG)/(377d2) --> E=0.0796xPxG/d2 Where E=Field strength in Volts/meter P=Power in Watts G =Numeric antenna gain d =Distance in meters S =Power density in milliwatts / square centimeter ; n$ \3 b9 q4 V
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. v `3 L) Z( E9 g V# g8 M - B) Friis transmission formula: Pd = (Pout*G)/(4* Pi * R2)
- --> Pd = 1000*P*G / 4*pi*10000 r2
- --> Pd = 0.00796 * P * G / r2
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Where Pd = power density inmW/cm2 Pout = output power toantenna in mW G = gain of antenna inlinear scale Pi = 3.1416 R = distance betweenobservation point and center of the radiator in cm : d" t1 a' }8 E5 u$ t5 n
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