The clean-room reverse engineering team that helped generate the specs for the bcm43xx driver for Linux derived a formula for the noise value based on the original driver and guessed that the results were in dBm. The current version of the Linux driver follows these formulas (as far as I can tell) and generates a value of -60 to -70 for a Linksys WPC54G Cardbus card. For the rssi value when operating at 11 Mbps and at an unobstructed distance of 2 m from the AP, I get
-25 dBm, which results in a S/N of 35 to 45, which seems low to me.
If you are running Linux and are using one of the other wireless drivers or ndiswrapper with a Broadcom card, please tell me the "Noise Level" printed by an iwconfig command. Alternatively, if there is a way to extract this information from a Windows machine, please tell me that. I could boot the BSOD OS and get it for my configuration.
Thanks, Larry