Calculate Radiation Intensity of Cell Phone 2in Away

[Mohd Taqi]

I want to calculate the radiation intensity of a cell phone which has a peak output power of about 2.0 W . The formula that I should use is I= P/A right?
How to calculate the area if the question only state the distance which is 2 inch from the cell phone?

 

[sophiecentaur]

If you assume that the radiated pattern is isotropic, then you use a sphere of 2 inch radius.
However, 2 inches is very much in the near field and the proximity of the tissue will modify that assumed pattern quite radically. (And you can't get totally isotropic antennae, anyway)
You could always work with the worst case figure and assume that all of the 2W goes into the area round the user's ear (make some sort of arbitrary assumption about that). I doubt that you could do better than that, aamof.
There must have been several studies on what you want to know and a thorough google search would be worth while.