sdynpy.signal_processing.sdynpy_generator.sine_sweep

• Module: sdynpy.signal_processing.sdynpy_generator

• Source: GitHub

Signature¶

def sdynpy.signal_processing.sdynpy_generator.sine_sweep(dt, frequencies, sweep_rates, sweep_types, amplitudes=1, phases=0, return_argument=False, return_frequency=False, return_amplitude=False, return_phase=False)

Generates a sweeping sine wave with linear or logarithmic sweep rate

Parameters¶

• dt : float The time step of the output signal

• frequencies : iterable A list of frequency breakpoints for the sweep. Can be ascending or decending or both. Frequencies are specified in Hz, not rad/s.

• sweep_rates : iterable A list of sweep rates between the breakpoints. This array should have one fewer element than the frequencies array. The ith element of this array specifies the sweep rate between frequencies[i] and frequencies[i+1]. For a linear sweep, the rate is in Hz/s. For a logarithmic sweep, the rate is in octave/s.

• sweep_types : iterable or str The type of sweep to perform between each frequency breakpoint. Can be ‘lin’ or ‘log’. If a string is specified, it will be used for all breakpoints. Otherwise it should be an array containing strings with one fewer element than that of the frequencies array.

• amplitudes : iterable or float, optional Amplitude of the cosine wave at each of the frequency breakpoints. Can be specified as a single floating point value, or as an array with a value specified for each breakpoint. The default is 1.

• phases : iterable or float, optional Phases of the cosine wave at each of the frequency breakpoints. Can be specified as a single floating point value, or as an array with a value specified for each breakpoint. Be aware that modifying the phase between breakpoints will effectively change the frequency of the signal, because the phase will change over time. The default is 0.

• return_argument : bool If True, return cosine argument over time

• return_frequency : bool If True, return the instantaneous frequency over time

• return_amplitude : bool If True, return the instantaneous amplitude over time

• return_phase : bool If True, return the instantaneous phase over time

Returns¶

• ordinate : np.ndarray A numpy array consisting of the generated sine sweep signal. The length of the signal will be determined by the frequency breakpoints and sweep rates.

• arg_over_time : np.ndarray A numpy array consisting of the argument to the cosine wave over time.

• freq_over_time : np.ndarray A numpy array consisting of the frequency of the cosine wave over time.

• amp_over_time : np.ndarray A numpy array consistsing of the amplitude of the cosine wave over time.

• phs_over_time : np.ndarray A numpy array consisting of the added phase of the cosine wave over time.

Raises¶

• ValueError

• If the sweep rate and start and end frequency would result in a negative

• sweep time, for example if the start frequency is above the end frequency

• and a positive sweep rate is specified.