Antenna is in size of 0.5[m] X 0.5[m], with transmit frequency of 10GHz. In a distance of 100m the electric field is 250 [V/m]. I calculated the density of power with the formula: 0.5*(E^2)/(120*pi) and got: 82.891(adsbygoogle = window.adsbygoogle || []).push({});

[W/m^2].

the question is: can I calculate the density of power again but un distance of 10m?

My other question is: If I have a known G (G=a*D) can i find an expression for the total power comes from the antenna?

Can I use the formula: Pt=S*(4*pi*r^2)/G ? where Pt is total power and S is power in distance r. after I get Pt do I need to multiply it by the size of antenna?

Hi, I need the answer as quickly as possible. Thanks!!

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# Homework Help: Density of power of Antennas?

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