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! k3 J4 D5 z( C, O) s# Z7 W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 % V% B8 p- {- i: u1 {( w' U
--> 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 # V0 k9 S8 E% z4 K+ h/ h# S* q
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9 U# h$ `4 B* s$ d. l3 p - B) Friis transmission formula: Pd = (Pout*G)/(4* Pi * R2)
- --> Pd = 1000*P*G / 4*pi*10000 r2
- --> Pd = 0.00796 * P * G / r21 o! d; r0 O/ \6 N# N4 D9 Y
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 4 b, D5 o1 G0 ]: L7 h& I( I# ~
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