 It is commonly used in link budgets as the denominator of the important figure-of-merit ratios, such as carrier-to-noise-density ratio as well as "E""b"/"N"0 and "E""s"/"N"0.If the noise is one-sided white noise, i.e., constant with frequency, then the total noise power "N" integrated over a bandwidth "B" is "N" = "BN"0 (for double-sided white noise, the bandwidth is doubled, so "N" is "BN"0/2).This is utilized in signal-to-noise ratio calculations.