Use Your Waterfall View to Answer “Why?”

Use Your Waterfall View to Answer “Why?”

While I was tinkering with a Java-based Graphical frontend to Iperf called “JPerf” and I thought it would be cool to visually show how data being pushed through the physical 2.4GHz band looks like in Chanalyzer Pro. I was primarily interested in seeing how a microwave oven will affect data throughput. When running the throughput test I turned the microwave oven on. Wi-Spy with my little ..er.. Wi-Spy, microwave interference! Too bad these views tell you little about the cause of the problem. Wouldn’t it be nice if you could zoom into this point in time to see what happened? With Chanalyzer Pro you can!

Throughput Test Using Wi-Spy, Chanalyzer and IPerf

Narrow in on the Waterfall View for those Details, Details, Details!

Finding the source of your troubles is just a click away. Notice how the first highlighted box on the left still represents the Iperf graph above.

Time Segment A

Before I started the throughput test there were some APs broadcasting beacons in BPSK modulation. These are represented in Chanalyzer Pro’s Density View as curved shapes hovering over a Wi-Fi Channel.

Time Segment B

This is a time segment where throughput was at its highest. We can see that the AP on channel 1 jumped to 802.11n 40MHz-wide channel bonded transmission. In the density view high activity is represented by brightness. The colors are very bright for the 802.11n broadcast. We can still see the curvature of the AP on Channel 11.

Time Segment C

We no longer see the curvature of the access point on channel 11. A hill of activity ranging from channel 6 to channel 13 appears where we once saw the AP. The Wi-Fi on Channel 1 appears less bright and the shape is less defined indicating something changed.