BWHT

Data are whitened (increased bandwidth). The user defines a number of overlapping frequency bands which are individually subjected to Automatic Gain Control (AGC), and then reassembled into a whitened product. Highly nonlinear, but may reveal details in the data by overcoming dynamic range limitations in traditional plots of data. The command line arguments:

 bwht  infil  twide  fcent  bwdth  froll 
  
 infil:    =input file to be filtered 
 twide:    =AGC window length in sec.  
 fcent:    =center frequency (Hz)
 bwdth:    =bandwidth (Hz)
 froll:    =roll off (Hz)

EXAMPLE: bwht c008.seg .4 50. 80. 10.
We can view the bwhtc008.lst file to see the filter details. See Figure 97.

  Parameters:  
  twide=       0.40
  freqc=      50.00
  bwdth=      80.00
  deltf=      10.00
  nfilt=     9
  number of points in filter=        201
      J    F_Center (Hz)
      1          10.00
      2          20.00
      3          30.00
      4          40.00
      5          50.00
      6          60.00
      7          70.00
      8          80.00
      9          90.00

Figure 97: BWHT: 0.4 second AGC window, 50 Hz center, 80 Hz bandwidth, 10 Hz rolloff. Input data c008.seg are same as in Figure 91A.