I don't often feature vendor newsletters, but this morning I got this newsletter from B&B Electronics, in Ottawa IL.
The two definitions of packet sniffers are great, but the best of the newsletter is the link to "The Ten Commandments of Wireless Connectivity" also on their site. This is a great read, and very valuable information.
I offer just the first one here, to whet your whistle. The rest you will have to read on B&B's website.
1. Thou shall know thy dBm and recall thy high school logarithms.
Radio Frequency (RF) power is measured in milli Watts (mW) or, more usefully, in a logarithmic scale of decibels (dB), or decibels referenced to 1 mW of power (dBm). Since RF power attenuates as a logarithmic function, the dBm scale is most useful. Here are some examples of how these scales relate: