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Let's assume there is an emitter and a reciver. As the emitter is usually omni-directional, the reciver may get one direct wave and some reflected waves. Why does not these waves influence each other (they might even cancel themselves) and how it is solved the latency issue (a packet comes faster on direct wave than on reflected waves)?

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    \$\begingroup\$ Reflected waves may or may not have a different polarization. The waves can influence each other. en.wikipedia.org/wiki/Multipath_propagation This may also be partially corrected for in certain complex systems if I remember correctly. \$\endgroup\$ – HL-SDK Jan 5 '14 at 19:13
  • \$\begingroup\$ Can you explain more about the "latency issue" you refer to? \$\endgroup\$ – Andy aka Jan 5 '14 at 19:50
  • \$\begingroup\$ Are you referring to a path length difference (direct compared to indirect) which could delay the signal by by odd integer multiples of half wavelengths? \$\endgroup\$ – JIm Dearden Jan 5 '14 at 20:01
  • \$\begingroup\$ Yes, I am reffering to the path length difference. I do not know if it is enough for a bit to get twice to the reciver, but I think it might be an issue anyway. \$\endgroup\$ – Paul92 Jan 5 '14 at 22:10
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Why does not these waves influence each other (they might even cancel themselves)

This absolutely happens. In fact, much of the strength of 802.11N is derived from its ability to use MIMO to take advantage of the multiple paths that the environment provides.

The latency issue is (partially) solved by using Automatic Gain Control (AGC).

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