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DbmdBm is an abbreviation for the dB referenced to one milliwatt. Note 1: dBm is used in communication work as a measure of absolute power values. Zero dBm equals one milliwatt. A 3 dBm increase represents roughly doubling the power, which means that 3 dBm equals 2 milliwatt. For a 3 dBm decrease the power is reduced by one half, making -3 dBm equal to 0.5 milliwatt. Other values can be calculed using dBm = log10 (mW)*10 or mW =10^(dBm/10). Below is table summarizing useful values: 40 dBm 10 watts 36 dBm 4 watts 30 dBm 1 watts 27 dBm 500 milliwatts 26 dBm 400 milliwatts 25 dBm 320 milliwatts 24 dBm 250 milliwatts 23 dBm 200 milliwatts 22 dBm 160 milliwatts 21 dBm 130 milliwatts 20 dBm 100 milliwatts 15 dBm 32 milliwatts 10 dBm 10 milliwatts 5 dBm 3.2 milliwatts 4 dBm 2.5 milliwatts 3 dBm 2.0 milliwatts 2 dBm 1.6 milliwatts 1 dBm 1.3 milliwatts 0 dBm 1.0 milliwatts -1 dBm 0.79 milliwatts -5 dBm 0.32 milliwatts -10 dBm 0.1 milliwatts -20 dBm 0.01 milliwatts -30 dBm 0.001 milliwatts -40 dBm 0.0001 milliwatts -50 dBm 0.00001 milliwatts -60 dBm 0.000001 milliwatts -70 dBm 0.0000001 milliwatts -80 dBm 0.00000001 milliwatts Note 2: In DOD practice, unweighted measurement is normally understood, applicable to a certain bandwidth, which must be stated or implied. Note 3: In European practice, psophometric weighting may be implied, as indicated by context; equivalent to dBm0p, which is preferred. See also Zero dBm transmission level point Source
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