Last Post: May 24, 2007:
The way the RSSI value is calculated and reported is up to the vendor. Some use a percentage, or dBm value while others use a poor, good, excellent reporting. Some calculate on signal strength, some on available bandwidth and other use both or a proprietary means. This is from the 1999 802.11 standard page 150. The last sentence is what bothers me the most. 802.11k may offer some help when completed.
126.96.36.199 RXVECTOR RSSI
The receive signal strength indicator (RSSI) is an optional parameter that has a value of 0 through RSSI
Max. This parameter is a measure by the PHY sublayer of the energy observed at the antenna used to receive
the current PPDU. RSSI shall be measured between the beginning of the start frame delimiter (SFD) and the
end of the PLCP header error check (HEC). RSSI is intended to be used in a relative manner. Absolute accuracy of the RSSI reading is not specified.