User's Manual

SPEEDLAN 8500 Series Installation and Operation User Guide
Analyzing Wireless Equipment 13-7
Important Wireless Statistics
Some of the most important wireless statistics are the following:
• Link Quality
This displays the quality of the link.
• Green = Good activity
• Yellow = Acceptable activity
• Red = Poor activity
• SNR (Signal-to-Noise Ratio)
The ratio of the standard description of the signal to the standard deviation of the noise.
• Signal
Again, the higher the signal level, the better. In order for the link to be successful, you
should have a signal level approximately 20 points higher than the noise.
• Noise
Since the spread spectrum signals run clearly, the noise level is usually very low. The lower
the noise, the better.
• Packets
This displays the percentage of test packets successfully received at each end. A higher per-
centage is better.
If you are loosing a large percentage of packets, try realigning the antenna or
changing its polarization (keeping in mind the antenna polarization must be the same
at both ends of the wireless link. Then, run the wireless link test again.
• Log
You can log the results of the link test into an ASCII text file. You can run the performance
over time and create a graphic to view the past to current results.
8 To exit this test, click Quit. Rerun the wireless link test after you have configured each IDU
or implemented any antenna alignments to verify that all equipment is communicating suc-
cessfully.
9 Fine tune antennas to maximize signal level at each site and repeat the link test again to
confirm good performance.
TIP