Polycom SpectraLink 8020 Deployment Manual page 11

Deploying SpectraLink 8020/8030
Wireless Telephones
July 2009
Figure 2 - 802.11b/g Non-interfering Channels with Overlapping Cell Coverage
If adjacent access points in three dimensions (above, below or beside) are set to the same channel, or
utilize channels with overlapping frequency bands, the resulting interference will cause a significant
reduction in the network performance and throughput, and will degrade overall voice quality. A channel
space of twenty five MHz, five channels or greater should be used to configure neighbor APs for non-
interfering channels Figure 3 represents the 2.4 GHz frequency range, indicating the overlap in channel
frequencies.
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2400 MHz
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1
With more available channel options, the 802.11a standard has improved the flexibility of WLAN layouts,
and enabled the possibility for greater density of APs. In an 802.11a deployment, all 23 channels are
technically considered non-overlapping, since there is 20 MHz of separation between the center
frequencies of each channel. However, because there is some frequency overlap on adjacent 802.11a
channel sidebands, there should always be at least one cell separating adjacent channels and two cells
separating the same channel. This methodology is depicted in Figure 4.
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22 MHz
Figure 3 - 802.11b/g Channels
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Best Practices Guide
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2483 MHz