Signal to Noise Ratio
Signal to Noise Ratio report reveals lowest overall radio frequency (RF) signal-to-noise (SNR) percentages observed for the selected duration. SNR is particularly important for wireless networking for ensuring QoS for voice and other continuous media traffic over IP. When measured in dB, SNR should fall between 25 and 40 dB —where:
- SNR >= 40dB. Excellent.
- 25dB < SNR < 40dB. Good.
- SNR < 25dB. Poor.
SNR is calculated by subtracting the wireless signal strength from that of the noise floor. Poor signal to noise ratio can occur due to hardware transmit issues, nearby devices emitting radio frequency interference (RFI), and other sources of higher than normal RFI present in the ambient that combine to contribute to the normal background noise also referred to as the noise floor.
- . Device hostname, IP address, or custom label.
- . Lowest average signal to noise ratio observed during the selected interval.
- . Highest average signal to noise ratio observed during the selected interval.
- . Average signal to noise ratio for the selected time interval.
: Percentages reported likely will never reach 0 or 100. Generally, An SNR of 40% is considered good. Anything less than 20% is considered poor.
Generate a report
. Choose one or more host devices you want Signal to Noise Ratio measurements for.
Use the Select Device dialog for one of the following:
Control
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Purpose
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Device
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Browse and choose a single device.
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Single Interface
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Choose an interface on a device.
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Device Group
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Choose an existing group of one or more devices. You can also create custom or dynamic groups.
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: You can organize devices into custom or dynamic groups. For more information, see Grouping Devices.
. (,) Choose times for the Signal to Noise Ratio. (For recently observed measurements, select from the Date Range drop down list.)
Choose time constraints for data view
Control
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Purpose
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Date Range
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Choose or define an overall date range.
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Business hours
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- Focus on specific days of the week and periods within each day.
- Reveal trends that are sensitive to business hours, time zones, and other periodic attributes in the observed data.
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. Sort and remove columns, group rows based on specific column values, and remove unwanted information from the table.
Filter and pick by column
Click a report heading and use the following from the drop down list:
Control
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Purpose
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Sort.
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Sort column in ascending or descending order.
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Columns.
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Pick the columns you want to view. Click a check box to display the column. Clear the check box to hide it.
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Group by this field.
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Group table into collapsible rows wherever the current column contains identical data ("field") values.
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Filters.
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Provide a keyword to view only rows that contain the keyword for this column.
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. Fine tune report presentation and range of values displayed using the Report Settings dialog (optional).
Specify threshold and top n:
Control
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Purpose
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Show Top n Items
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Limit items to the samples with the highest (or lowest) interface errors.
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Threshold Type
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Switch between minimum or maximum mode for cutoff values for the ranked list.
- At or Over. Show peak occurrence period. (Observations equal to or greater than Threshold.)
- At or Under. Show occurrences equal to or less than Threshold.
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Threshold (percent)
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Baseline value used to trim ranked device list based on peak or subpeak periods when returning the Top n.
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Chart and visualize data over time (single device )
Charting and visualization is available when you select a single device.
Control
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Purpose
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Display Options
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Present data as a chart, a table grid, or both.
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Chart Type
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- Gauge charts. Available when you select a Date Range of .
- Time series. Available when you select a Date Range interval (, for example).
- Line/Area. Scatter graph that connects adjacent measurements with straight lines.
- Spline/Area Spline. Choose a graph with a smoothed appearance where adjacent samples exhibit a gradual slope.
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Chart Options
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- Legend, Grid Lines, Range Selector. Include legend, grid lines, and range selector for readability.
- Trend Lines. Present data with a smoothed average to show trend.
- Vertical Axis Scale. Automatically scale to fit data or specify a finite range.
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: Trend lines represent a moving average that can be compared with line and area graphs to reveal peak and sub peak intervals, collision periods, and indicate transmission problems.
: This report only returns Signal to Noise Ratio metrics for devices that already have the appropriate WMI or SNMP credentials. For more information, see Using Credentials.
Export report data
Report data can be exported from WhatsUp Gold, reused, and distributed in multiple formats. Select () from the Dashboard Options () menu. After the report has been expanded, select the Export Data icon to access the following options:
- . Generate and download a .htm file presenting your report data as it appears in the WhatsUp Gold user interface.
- . Generate and download a .xml spreadsheet containing your report data.
- .Generate and download a .csv file containing your report data.
- Generate and download a .txt file containing your report data.
- . Set a recurring date and time, format, and email destination for report data export.
: Current report data file format options are only applicable to export schedules created using WhatsUp Gold version 2021 and later. Any report data export schedule created using an earlier version of WhatsUp Gold will still result in a .PDF output until that schedule is removed from, then recreated in the Scheduled Reports Library using the latest version of WhatsUp Gold.