Generally power is expressed in watts. The gain is the ratio of the output power to the input power. Gain = (output power)/(input power) if the gain is expressed in terms of log(base10) it is known as Decibel power gain Decibel power gain = Log10(Gain)dB if 1milliwatt power is taken as reference then Decibel power gain = Log10(Output power/1 milliwatt)dBm

a sign of a country's relative power

the Phoenicians gain power by...answer coming soon.

The conversion gain, G, is one of the standard values usually measured and

quoted to indicate the performance of a heterodyne or superheterodyne

receiver system. G is called a 'gain' because it is a ratio of an output power

to an input power. In most practical cases the actual output power is smaller

than the input, so it would be more honest to call it a loss Despite this, the

convention is to call it a gain, even if it is a gain of -10dB's, the output is ten

times smaller than the input. It is called a 'conversion' gain because it indicates

the relative level of an output which has been converted to a frequency which

differs from that of the input.