Power Amplifier

The power amplifier is usually the last stage in a transmitting device’s radio frequency chain before the antenna. This base model is HermesPy’s default power amplifier model, which is a linear amplifier with a constant gain and therfore no distortion

\[s'(t) = s(t) \text{,}\]

which may be overwritten by classes inheriting from this base.

class PowerAmplifier(saturation_amplitude=inf, adjust_power=False)

Bases: Serializable

Base class of a distorionless power-amplifier model.

Parameters:

• saturation_amplitude (float, optional) – Cut-off point for the linear behaviour of the amplification in Volt.

• adjust_power (bool, optional) – Power adjustment flag.

model(input_signal)

Model signal amplification characteristics.

Parameters:

input_signal (np.ndarray) – Sample vector of the signal feeding into the power amplifier.

Returns:

Distorted signal after amplification modeling.

Return type:

np.ndarray

plot_characteristics(axes=None, *, title=None, samples=None)

Plot the power amplifier distortion characteristics.

Generates a matplotlib plot depicting the phase/amplitude.

Parameters:

• axes (VAT, optional) – The axis object into which the information should be plotted. If not specified, the routine will generate and return a new figure.

• title (str, optional) – Title of the generated plot.

• samples (np.ndarray, optional) – Sample points at which to evaluate the characteristics. In other words, the x-axis of the resulting characteristics plot.

Return type:

Figure

send(input_signal)

Model signal amplification characteristics.

Internally calls the model subroutine of power-amplifier models implementing this prototype-class.

Parameters:

input_signal (np.ndarray) – Sample vector of the signal feeding into the power amplifier.

Returns:

Distorted signal after amplification modeling.

Return type:

np.ndarray

adjust_power: bool

Power adjustment flag.

If enabled, the power amplifier will normalize the distorted signal after propagation modeling.

property saturation_amplitude: float

Cut-off point for the linear behaviour of the amplification.

Referred to as \(s_\mathrm{sat} \ \mathbb{R}_{+}\) in equations.

Returns:

Saturation amplitude in Volt.

Return type:

float

Raises:

ValueError – If amplitude is smaller than zero.

property title: str