RSSI value in dBm about rtl-wmbus

[pswiatki]

I guess there is no way that is reasonable. You see: AGC is enabled as far as I know and it changes as necessary during the reception.

[xaelsouth]

Hello pbasista,

you can calculate dBm instead of RSSI by using following formula even it doesn't make much sense, see below:

dBm = 10 * log10[ (I^2 + Q^2) / (2 * R * 0.001) ]

Where R is receiver's input impedance, which is typically 75 ohms for DVB-T receivers (some of them have got 50 ohms!), referenced to 0.001W.

This formula can be applied only if no AGC comes into play, as pswiatki has already mentioned. Digital receivers usually take AGC into account and put a corrected RSSI and/or dBm value into their registers.

Xael