That assumes they're proper "power" decibels (10 x log 10 (P1 / P2))
I always assumed they're actually voltage based (20 x log 10 (V1 / V2))
If anyone knows for sure which is right, I'd appreciate the information
You are right, but RSSI is normally in dBm, dBW, dBk or similar.
Your formula of 20 x log 10
) is only used when comparing power levels based on voltage or amplitude measurements. and is equivalent to 10 x log 10
) and if you work out a drop of 3dB using either of your formulas the first gives 0.5x power and te second 0.71x voltage which (assuming a constant impedance) gives 0.5x power.
M H C
taurus excreta cerebrum vincit
Edited by MHC (Thu 23-Jun-11 23:56:42)