Monitoring RF Signal-to-Noise Ratio
Signal-to-noise ratio (SNR) is a measure of the level of a desired signal against the level of background noise, measured in decibels (dB). Think of having a conversation in an empty restaurant where your signal (your voice) is clearly heard. Now, think of that same restaurant at noon, when the background noise (all other conversations) is at a peak. You will need to talk louder and lean closer to be heard at noon. In other words, you must increase your signal to overcome the background noise.
Signal-to-noise ratio, along with the bandwidth and channel capacity of a communication channel, affects throughput (see Monitoring RF Throughput), especially video throughput.
To view the signal-to-noise ratio on a radio over a fixed period of time:
- Select Monitor Mode in the Network Director banner.
- Select any view from the View pane.
- Expand the wireless list in the View pane, then select
a radio.
The Monitor mode RF tab becomes available when you select a radio. The Signal-to-Noise Ratio monitor becomes available only when you select a radio.
- Click the Monitor mode RF tab to view the four
basic monitors for radios, which includes the Signal-to-Noise Ratio
monitor.
By default, the populated Signal-to-Noise Ratio monitor graph uses throughput that the selected object has experienced over the last hour.
- Optionally, change the timeframe covered by the monitor by selecting a different time from the list.
- Click Help (?) for help interpreting the throughput chart or see Signal-to-Noise Ratio Monitor.
 | Note: To change the polling interval for monitors, see Setting Up User and System Preferences. |
If you are using MSS version 8.0 or higher, you can try using Transmit beam-forming (TxBF) to improve your SNR values. TxBF is a technique that uses an array of transmitting antennas to send radio signals with adjusted magnitude and phase at each antenna to achieve a focused beam target to the receiver. TxBF can increase the Signal-to-Noise Ratio (SNR) at the receiver and improve performance. This feature is supported on the WLA532, WLA321, and WLA322, and is configured from the MSS CLI.
