Scanning ODU Frequency Interference

This topic describes how to use the U2000 Web LCT for frequency scanning. When channel interference occurs, the commonly-used method is using special instruments to check whether interference occurs on transmit frequencies. However, using special instruments to scan frequencies is not cost-effective. Instead, you can use the automatic frequency scanning function provided by the U2000 Web LCT.

Prerequisites

The microwave link must be created.

Context

Microwave Links may be interrupted due to various causes, such as link deterioration, equipment faults, and link interference. In areas that widely use radio equipment for communication, because frequency resources are insufficient and channels are highly multiplexed, channel interference is severe and may cause the following problems:

During site installation, links may suffer interference and are interrupted if network planning data is not updated in time.
During O&M, sites may interfere with each other and cause link interruption.

Instrument-based frequency scanning is not cost-effective. The U2000 Web LCT provides a cost-effective method to check for interference on different channels of a sub-band.

NOTE:

This function applies only to the local ODU. Frequency scanning on the remote ODU is not supported.

NOTICE:

Microwave Links will be interrupted when you scan the frequencies on an ODU that is transmitting signals.

Procedure

In the NE Explorer, choose Diagnosis&Maintenance > ODU Frequency Scan from the navigation tree.
Select the desired ODUs and set Frequency range(MHz) and Frequency Adjustment(MHz). Use the default value of Auto Disabling Time (min). Click Start Frequency Scanning.
NOTE:
- The disabling time applies only to the remote ODU. The RTN equipment will calculate the disabling time of the remote ODU automatically based on the frequency range and frequency adjustment. The longer the frequency adjustment, the shorter the disabling time. Therefore, the default value is recommended.
- If you select the Mute Peer Transmit Status check box, local and peer ODUs are both muted after frequency scan starts. When the scan is complete, the local ODU will resume the transmit status and RF parameters will resume their original values; the peer ODU will resume the transmit status after Auto Disabling Time (min) is due.
- If you clear the Mute Peer Transmit Status check box, the peer ODU is not muted and the value of Auto Disabling Time (min) is not changed after frequency scan starts.
Optional: During the scanning, you can click Stop Frequency Scanning to stop it.
After the scanning is complete, you can view the scan result in a graph or table.
1. Click the Scan Result Image tab to view the scan result in a graph.
  NOTE:
  If the transmit frequencies and receive power form a straight line parallel to the X axis, frequencies are not interfered with on the local ODU. If some frequency dots deviate from the straight line, interference exists on these dots.
2. Click the Scan Result Table tab to view the scan result in a table.