Aerohive HiveAP 20, Руководство по развертыванию

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Deployment Guide 21
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Microwave ovens, wireless video cameras, Bluetooth headsets, and cordless phones can all interfere with Wi-Fi
signals (see
Figure 5 ). Excess noise in an environment is often difficult to diagnose and can have a major negative
impact on network performance. To discover noise sources, a spectrum analysis system is needed. AirMagnet
provides an affordable spectrum analysis tool that operates in the 2.4 GHz and 5 GHz spectra.
Figure 5 Path Loss with Noise (from Microwave)
Now that you have a sense of how Wi-Fi performance changes over distance and with noise, look at some ways to
perform channel assignment. If two access points are on the same channel right next to each other, they are forced
to share the same spectrum. This means that they share the 54 Mbps available in 802.11a/g rather than each being
capable of 54-Mbps speeds independently. This essentially halves the bandwidth for each access point. To manage
this situation, make sure that neighboring APs are on different channels and that their power is adjusted so that it
does not overlap that of other APs with the same channel.
In the 2.4 GHz spectrum, there are 11 channels in the United States. However, a Wi-Fi signal consumes more than
one channel. Consequently, there are only 3 non-overlapping channels: 1, 6, and 11. To achieve optimal
performance, you need to design a channel layout pattern such as the one on the left in
Figure 6 .
Figure 6 Channel Layout Patterns
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