Velocity decontamination by cospectral methods

From Atomix

Short page on cospectral techniques for wave pumped surface buoys, and standard coherence (similar to shear probe techniques) when the contamination is vibration related.

  • Basically, if you need to decontaminate the spectra for motion using any cospectral technique.. you must ensure a fairly large degrees of freedom so that the calculation is meaningful.
  • As a rule of thumb, I like to target over 50 dof, which is achievable when using
** 7 blocks i.e., diss-length that is 4x fft-length and  band-averaging over 3 frequencies to retain samples over the lower frequencies (and increase number of spectral obs over the inertial subrange)
** 9 blocks i.e., diss-length that is 5x fft-length (no band-averaging)