Performance of split-window multipass-mean noise spectral estimators

Spectrogram background normalization for narrowband passive acoustic detect ion systems has a long history, and the split-window three-pass mean noise spectral estimator (S3PM NSE) is currently a standard in this regard. As ye t, however, there is no analytical design methodology for choosing the wind ow parameters and shearing thresholds for the S3PM NSE. That deficiency is remedied here by deriving an approximation for the bias of the S3PM NSE whe n its input is colored Gaussian noise.