calc_rf_power

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calc_rf_power#

pypulseqpp.calc_rf_power()[source]#

Return an RF event’s energy, peak power and RMS amplitude, as MATLAB Pulseq’s calcRfPower.

Parameters:

  • rf (RF event) – Anything with t (s), signal (Hz) and shape_dur (s).

  • dt (float, default=1e-06) – Resampling step, in seconds.

Returns:

  • total_energy (float) – Integral of |rf|^2, in Hz^2 s.

  • peak_pwr (float) – Largest |rf|^2, in Hz^2.

  • rf_rms (float) – sqrt(total_energy / shape_dur), in Hz.

Notes

The pulse is resampled at the midpoints of a dt grid over its shape duration, zero outside its samples. A dynamic pTx pulse is resampled channel by channel on its shared time base, and |rf|^2 is the sum of |b_c|^2 over channels: its root-sum-square amplitude, which channels cannot cancel. The quantities are relative: divide rf_rms by gamma for tesla and energy by gamma squared for T^2 s.

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