Summary/Cause:
To facilitate optimal operation in frequency scenarios, PTP 820E include a frequency scanner that enables you to scan a defined frequency range and determine the current interference level for each channel.
The frequency scanner can be used both in the initial provisioning of the link and at any time after the link has been provisioned. The scanner determines the interference level for each RX channel. Using this information, you can select the channels with the least interference, and configure the unit’s frequency accordingly.
When the frequency scan begins, the unit stops receiving traffic until the scan is complete. This means the link is effectively down while the frequency scanner is operating. Once the frequency scan operation has been completed, either at the end of a Single Mode scan or by user action in the case of a Continuous scan, the link is automatically restored at the same frequency settings as before the scan.
Note: The frequency scanner does not automatically change the link’s frequency settings. These settings must be changed manually. The frequency scanner simply provides information you can use in determining the proper frequency configuration.
Solution:
1 To perform a frequency scan:
Select Radio > Frequency Scanner. The Frequency Scanner page opens
Frequency Scanner Page – Continuous Mode
Frequency Scanner Page – Single Mode
2 Enter a range for the scan (in MHz) by entering the lower frequency of the range in the Start Frequency field and the upper frequency of the range in the Stop Frequency field. The range of permissible values is 81000-86000 MHz on the high side and 71000-76000 MHz on the low side
3 In the Scanner Mode field, select from the following options:
Continuous Mode – The frequency scanner scans each channel in the script, and repeats the scan continuously until you manually stop the scan by clicking Stop. For each channel, the Web EMS will display the minimum, maximum, and most recently measured interference levels, in both table and graph formats
Single Mode – The frequency scanner scans each channel in the script once, over the defined frequency range. For each channel, the Web EMS will display the measured interference level.
Note
When running the Frequency Scanner on the remote side of a link using inband management, make sure to run the Frequency Scanner in Single mode, not Continuous mode. Since the link is down during the scan, management to the remote site is lost, so that if the scan is run in Continuous mode, it will not be possible to de-activate the Frequency Scanner
4 Click Apply to save the scan configuration.
5 Click Scan
The Scan Progress field displays the scan’s progress, in percentage of the defined spectrum that has been scanned. In Continuous Mode, the Scan Progress field rises to 100 when the defined spectrum has been scanned, returns to 0, and continues to advance from 0 to 100 for each scan until you click Stop. In Single Mode, the Scan Progress field rises to 100 and stays at 100 once the defined spectrum has been scanned
The Frequency Scanner Band field displays the frequency channel configured in the current MRMC script
The Last Scan Date and Time field displays the date and time of the most recently completed frequency scan
Scan results are displayed in table format, and can also be displayed in graph format. In Single Mode, results are displayed after the scan is completed. In Continuous Mode, results are displayed after the scan has completed one cycle over the defined spectrum, and are automatically updated as the scan proceeds.
Below figure shows the results of a Continuous Mode scan and Single Mode scan on an PTP 820/850E in table format. For each RX channel in the defined frequency range, the table displays the following columns, additionally, the Graph page has the following tabs:
◦ Frequency (MHz) – The starting frequency in the scanned channel.
◦ RSL Sample Value (dBm) – In Single Mode, the RSL value measured for the scanned channel. In Continuous Mode, the latest RSL value measured for the scanned channel.
◦ Minimum RSL (dBm) – In Continuous Mode, the lowest RSL value measured for the scanned channel. In Single Mode, the same as the RSL Sample Value.
◦ Maximum RSL (dBm) – In Continuous Mode, the highest RSL value measured for the scanned channel. In Single Mode, the same as the RSL Sample Value.
You can also display the scan results in graph format by clicking Graph. The Graph page presents the scan results in graphical format, with the frequency on the horizontal axis and the RSL on the vertical axis.
Frequency Scanner Results – Graph Format (Continuous Mode)
Frequency Scanner Results – Graph Format (Single Mode)
