Understanding Basic Wireless Theory

To send data across a wired link, an electrical signal is applied at one end and is carried to the other end. The wire itself is continuous and conductive, so the signal can propagate rather easily. A wireless link has no physical strands of anything to carry the signal along.

How then can an electrical signal be sent across the air, or free space? Consider a simple analogy of two people standing far apart, and one person wants to signal something to other. They are connected by a long and somewhat-loose rope; the rope represents free space. The sender at one end decides to lift his end of the rope high and hold it there so that the other end of the rope will also raise and notify the partner. After all, if ...

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