cbadc.digital_control.dither_control.DitherControl

class cbadc.digital_control.dither_control.DitherControl(number_of_random_controls: int, digital_control: DigitalControl, impulse_response: List[_ImpulseResponse] = None, dithering=True, random_sequence_length=4194304, t_delay: float = 0.0)[source]

Bases: DigitalControl

A control with dither signal.

An extension to the traditional digital controls, that stabilize the digital dimension, where the dither control adds a randomly generated dithering signal to the mix.

Note that the dithering controls are prepended those of the initalizing digital control.

Parameters

number_of_random_controls (int) – number of dithering controls
digital_control (cbadc.digital_control.DigitalControl) – a digital control to be extended

Methods

`__init__`(number_of_random_controls, ...[, ...])
`control_contribution`(t)	Evaluates the control contribution at time t.
`control_signal`()	Returns the current control state, i.e, \(\mathbf{s}[k]\).
`control_update`(t, s_tilde)	Updates the control at time t if valid.
`impulse_response`(m, t)	The impulse response of the corresponding DAC waveform
`reset`([t0])	Reset the digital control clock
`turn_off_dither`()
`turn_on_dither`()

control_contribution(t: float) → ndarray

Evaluates the control contribution at time t.

Parameters: t (float) – time at which the digital control i evaluated.
Returns: the control signal \(\mathbf{s}(t)\)
Return type: array_like, shape=(M,)

control_signal() → ndarray

Returns the current control state, i.e, \(\mathbf{s}[k]\).

Examples

>>> from cbadc.digital_control import DigitalControl
>>> from cbadc.analog_signal import Clock
>>> import numpy as np
>>> T = 1e-6
>>> M = 4
>>> dc = DigitalControl(Clock(T), M)
>>> _ = dc.control_contribution(T)
>>> dc.control_signal()
array([0., 0., 0., 0.])

Returns: current control state.
Return type: array_like, shape=(M,), dtype=numpy.int8

control_update(t: float, s_tilde: ndarray)[source]

Updates the control at time t if valid.

Parameters

t (float) – time at which the digital control i evaluated.
s_tilde (array_like, shape=(M_tilde,)) – state vector evaluated at time t

impulse_response(m: int, t: float) → ndarray[source]

The impulse response of the corresponding DAC waveform

Parameters

m (int) – determines which \(m\in\{0,\dots,M-1\}\) control dimension which is triggered.
t (float) – evaluate the impulse response at time t.

Returns

the dac waveform of the digital control system.

Return type

array_like, shape=(M,)

reset(t0: float = 0.0)

Reset the digital control clock

Parameters: t0 (float, optional) – time to set next update at, defaults to 0.