Wavelets

stride.utils.wavelets.tone_burst(centre_freq, n_cycles, n_samples, dt, envelope='gaussian', offset=0)[source]

Generate a tone burst wavelet.

Parameters:
  • centre_freq (float) – Centre frequency of the signal.

  • n_cycles (float) – Number of cycles for the signal.

  • n_samples (int) – Length of the wavelet.

  • dt (float) – Discretisation step for the time axis.

  • envelope (str, optional) – Type of envelope to be applied to the signal, gaussian (default) or rectangular.

  • offset (int, optional) – Offset in timesteps to the start of the wavelet, defaults to 0.

Returns:

Generated wavelet.

Return type:

1-dimensional array

stride.utils.wavelets.ricker(centre_freq, n_samples, dt, offset=0)[source]

Generate a ricker wavelet.

Parameters:
  • centre_freq (float) – Centre frequency of the signal.

  • n_samples (int) – Length of the wavelet.

  • dt (float) – Discretisation step for the time axis.

  • offset (int, optional) – Offset in timesteps to the start of the wavelet, defaults to 0.

Returns:

Generated wavelet.

Return type:

1-dimensional array

stride.utils.wavelets.continuous_wave(centre_freq, n_samples, dt, ramp_length=4, phase=0)[source]

Generate a continuous wave.

Parameters:
  • centre_freq (float) – Centre frequency of the signal.

  • n_samples (int) – Length of the wavelet.

  • dt (float) – Discretisation step for the time axis.

  • ramp_length (int, optional) – Length of the up-ramp used to reduce start-up transients in periods, defaults to 4.

  • phase (float, optional) – Phase shift on the wave, in [rad]. Defaults to 0.

Returns:

Generated wavelet.

Return type:

1-dimensional array