In Use, Continued
Figure 6 shows the measurements made from my Location 3, which is a floor above, but closer (straight-line distance) to the test WLAN than Location 2. Once again the change in Cognio and Wi-Spy measurements track pretty well -65 to -75 dBm and -35 to -45 dBm respectively.
Figure 6: Wi-Spy and Cognio - Location 3
(click image to enlarge)
I also tried my more difficult Locations 4 and 5 and found that the Cognio could still capture a signal, while it was difficult to tell whether the Wi-Spy was really measuring anything or just random noise. It was these measurements made of low-level signals that convinced me that Wi-Spy users will probably find the Maximum Trace feature more useful than the Data (real-time) and Average traces.
I finally moved back to Location 3 and then ran a microwave oven that was located about 20 feet and a few walls away, with the results shown in Figure 7.
Figure 7: Wi-Spy and Cognio - Location 3 w/ Microwave
(click image to enlarge)
Due to the intermittent nature of the microwave interference (I ran it for only around 10 seconds), I had to rely on the maximum trace feature of both products, which produced remarkably similar results.