On 3/15/2013 8:19 PM, David Gilbert wrote:
No way that the respective wavefronts will add in all of those
directions. Geometry alone would tell you they are much more likely
to cancel in some directions.
Right. MANY directional arrays are the result of wavefronts from
multiple driven elements that add algebraically (magnitude and phase)
differently in different directions and elevation angles. Magnitude and
phase of any antenna varies with both horizontal and vertical angle, and
antennas will have some magnitude and phase relationships to each other
based on their spatial relationships.
Yes, we can drive two or three Yagis pointed in the same or different
directions, but HOW they combine to form a pattern can be as close to
the infinite number of monkeys and typewriters as it is to how the
operator thinks he is aiming them.
73, Jim K9YC
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