Re: Antenna gain question

Ron wrote:
Maybe I should restate my question. Assume a receiving antenna is in the center of a sphere and the received signal is coming in equal amounts from all points on the surface of the sphere. Which receiving antenna would capture more power, an omni or a high gain beam? There are no noise and no losses.

They'll intercept equal amounts, assuming both are lossless. The directional antenna will intercept a larger fraction than the isotropic antenna in the directions it favors, and less in others. The total will be be the same.

In reverse, this is equivalent to calculating the average gain of the antennas, which is the same for all lossless antennas.

Roy Lewallen, W7EL
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