On the contrary, most RF solutions
incur delay when advanced modulation techniques or error recovery techniques
are used. FSO systems generally do not use such techniques and thus add only
negligible delay. FSO is, therefore, well suited for wireless mesh applications.
250 Chapter 9
?– Density Higher density makes mesh networks more robust. However, creating a
dense mesh network may pose a challenge when you consider the wireless links. If
there are many links close to each other, the links may interfere with each other.
When using RF wireless, the problem may be alleviated by using a larger amount
of the RF spectrum in a mesh. However, this solution can be too costly due to the
licensing fee for the spectrum. FSO systems overcome this because of its narrow
beam and by using the unlicensed part of the spectrum. With divergence of about
1 degree for a typical system, links separated more than 2 degrees will not interfere
with each other.
?– Cost A mesh network is created by interconnecting multitudes of equipment. If
the cost of the underlying technology is fairly high, the overall cost of a mesh network
may skyrocket. For example, if RF wireless technology is used and spectral
licensing is required, the cost to deploy (and perhaps maintain) a wireless mesh
network could be prohibitive.
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