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Noise Power Calculations in dB or dBm

  1. Jun 30, 2011 #1
    The ourput Noise Power is given as
    No = kTsBG + kTeBG
    ....= k.(Ts+Te).B.G
    But when it is asked in dB or dBm,
    How to calculate it something like 10Log10(Value) or 20Log10(Value)
  2. jcsd
  3. Jun 30, 2011 #2


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    Science Advisor
    Gold Member

    dBm is a unit of power (dB referenced to 1 mW)
    dB is a (dimensionless) ratio (value/reference in dB).

    Hence, if you want noise power you need to use dBm.
    All you need is 10log10 (P/P0) where P is the power and P0 is 1 mW.
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