Signal Strength And Coverage - Cisco 9971 Deployment Manual

Signal Strength and Coverage

To ensure acceptable voice quality, the Cisco Unified IP Phone 9971 should always have a signal of -67 dBm or higher when
using 2.4 or 5 GHz and ensure the Packet Error Rate (PER) is no higher than 1%.
A minimum Signal to Noise Ratio (SNR) of 25dB = -92dBm noise level with -67 dBm signal should be maintained.
It is recommended to have at least two access points on non-overlapping channels with at least -67 dBm signal with the 25 dB
SNR to provide redundancy.
To achieve maximum capacity and throughput, the wireless LAN should be designed to 24 Mbps. Higher data rates (36-54
Mbps) can optionally be enabled.
Recommended to set the minimum data rate to 11 Mbps or 12 Mbps for 2.4 GHz (dependent upon 802.11b client support
policy) and 12 Mbps for 5 GHz, which should also be the only rate configured as a basic rate.
Due to the above requirements, a single channel plan should not be deployed.
For more information about signal strength and cell edge design, refer to the "VoWLAN Design Recommendations" chapter in
the Enterprise Mobility Design Guide at this URL:
http://www.cisco.com/en/US/docs/solutions/Enterprise/Mobility/emob41dg/eMob4.1.pdf
Cisco Unified IP Phone 9971 Wireless LAN Deployment Guide
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