User's Manual

Troubleshooting
8.10.1 Avoiding Interference
When a source of interference is identified and when the level and frequencies are known, the next step is to avoid the
interference. Some of the following actions can be tried:
• Change the channel to a frequency that has no or least interference.
• Try changing the antenna polarization.
• A small beam antenna looks only in one particular direction. Because of the higher gain of such an antenna, lowering
the output power or adding extra attenuation might be required to stay legal. This solution cannot help when the
source of interference is right behind the remote site.
• Adjusting the antenna angle/height can help to reduce the interference.
Move the antennas to a different location on the premises. This causes the devices to look from a different angle, causing a
different pattern in the reception of the signals. Use obstructions such as buildings, when possible, to shield from the
interference.
8.10.2 Conclusion
A spectrum analyzer can be a great help to identify whether interference might be causing link problems on the device.
Before checking for interference, the link should be verified by testing in an isolated environment, to make sure that the
hardware works and your configurations are correct. The path analysis, cabling and antennas should be checked as well.
Statistics in the web interface under Monitor indicates if there is a link, if the link is healthy, and a continuous test can be done
using the Link Test.
• Base Announces should increase continuously.
• Registration Requests and Authentication Requests should be divisible by 3. WORP is designed in a way that each
registration sequence starts with 3 identical requests. It is not a problem if, once in a while, one of those requests is
missing. Missing requests frequently is to be avoided.
• Monitor / Per Station (Information per connected remote partner): Check that the received signal level (RSL) is the
same on both sides. This should be the case if output power is the same. Two different RSLs indicate a broken
transmitter or receiver. A significant difference between Local Noise and Remote Noise could indicate a source of
interference near the site with the highest noise. Normally, noise is about -80 dBm at 36 Mbps. This number can vary
from situation to situation, of course, also in a healthy environment.
• Monitor / Link Test (Information used by Administrators for on-the-spot checking): Check the received signal level (RSL)
and noise level. Compare the RSL with the values from path analysis. If the figures differ significantly from the values
recorded at the Per Station window, check for environment conditions that change over time.
8.11 Miscellaneous
8.11.1 Unable to Retrieve Event Logs through HTTPS
If using Internet Explorer 7 and are not able to retrieve event logs through HTTPS, do the following:
1. Open Internet Explorer
2. Navigate to Tool > Internet Options > Advanced
3. Go to Security and uncheck/unselect Do not save encrypted pages to disk
Alternatively, use Mozilla Firefox 3.5 or later.
Tsunami® 8100 Series - Software Management Guide 218