Convert db to dbm

Here's how to convert dB units (with usually a 1 Watt or whatever 1 value as reference) to dBm units (with a 1 miliWatt reference value):

x= value to be converted


x [dB]= x + 30 [dBm]




Proof:
P= 1 Watt


--> 10*log10(1)= 0 [dB] (this is 1 Watt in dB)


--> 10*log10(1/(1*10^(-3)))= 10*log(1*10^3)= 30 dBm (this is 1 Watt to dBm)


Now, if you do whatever number of examples you want to do, you'll end up in concluding the conversion dB to dBm is totally linear without of actually having to proof the linear properties. (i'm too lazy to write it here).


Hope this helps....


Regards,


STMI