Determine
a. The power levels in dBm for signal levels of 10 mW and 0.5 mW.
b. The difference between the two power levels in dB.
a. The power levels in dBm are determined by substituting into Equation 3:
dBm = 10 log(\frac{P}{1\,mW}) (3)
dBm = 10 log(\frac{10\,mW}{1\,mW}) = 10 dBm
dBm = 10 log(\frac{0.5\,mW}{1\,mW}) = -3 dBm
b. The difference between the two power levels in dB is determined by substituting into Equation 2:
dB = 10 log(\frac{P_{1}}{P_{2}}) (2)
dB = 10 log(\frac{10\,mW}{0.5\,mW}) = 13 dB
or 10 dBm – (-3 dBm) = 13 dB
The 10-mW power level is 13 dB higher than a 0.5-mW power level.