! j9 p' D @) i# ^2 Z
: h0 j% X7 M5 Z5 O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 ( x$ r. B# t( z# j
--> 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 1 [$ w3 O' J, a# b4 a
* k$ E! Z8 j- f
0 @" ]0 i- C5 A2 K( l; } - B) Friis transmission formula: Pd = (Pout*G)/(4* Pi * R2)
- --> Pd = 1000*P*G / 4*pi*10000 r2
- --> Pd = 0.00796 * P * G / r2" l9 c* N% V2 t/ G# K
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
8 i+ J& F- U2 h5 b a |