Exponential

Exponentially decaying channel model. The following minimal example outlines how to configure the channel model within the context of a Simulation:

# Initialize two devices to be linked by a channel
simulation = Simulation()
alpha_device = simulation.new_device(carrier_frequency=1e8)
beta_device = simulation.new_device(carrier_frequency=1e8)

# Create a channel between the two devices
channel = Exponential(1e-8, 1e-7)
simulation.set_channel(alpha_device, beta_device, channel)

# Configure communication link between the two devices
link = SimplexLink()
alpha_device.transmitters.add(link)
beta_device.receivers.add(link)

# Specify the waveform and postprocessing to be used by the link
link.waveform = RRCWaveform(
    symbol_rate=1e8, oversampling_factor=2, num_data_symbols=1000,
    num_preamble_symbols=10, pilot_rate=10)
link.waveform.channel_estimation = SCLeastSquaresChannelEstimation()
link.waveform.channel_equalization = SCZeroForcingChannelEqualization()

# Configure a simulation to evaluate the link's BER and sweep over the receive SNR
simulation.add_evaluator(BitErrorEvaluator(link, link))
simulation.new_dimension('noise_level', dB(0, 2, 4, 6, 8, 10, 12, 14, 16, 18, 20), beta_device)

# Run simulation and plot resulting SNR curve

class Exponential(tap_interval, rms_delay, correlation_distance=inf, num_sinusoids=20, los_angle=None, doppler_frequency=0.0, los_doppler_frequency=None, antenna_correlation=None, gain=1.0, seed=None)

Bases: MultipathFadingChannel

Exponential multipath fading channel model.

Parameters:

• tap_interval (float) – Tap interval in seconds.

• rms_delay (float) – Root-Mean-Squared delay in seconds.

• correlation_distance (float) – Distance at which channel samples are considered to be uncorrelated. \(\infty\) by default, i.e. the channel is considered to be fully correlated in space.

• num_sinusoids (int) – Number of sinusoids used to sample the statistical distribution. Denoted by \(N\) within the respective equations.

• los_angle (float | None) – Angle phase of the line of sight component within the statistical distribution.

• doppler_frequency (float) – Doppler frequency shift of the statistical distribution. Denoted by \(\omega_{\ell}\) within the respective equations.

• antenna_correlation (AntennaCorrelation | None) – Antenna correlation model. By default, the channel assumes ideal correlation, i.e. no cross correlations.

• gain (float) – Linear power gain factor a signal experiences when being propagated over this realization. \(1.0\) by default.

• seed (int | None) – Seed used to initialize the pseudo-random number generator.

Raises:

ValueError – On invalid arguments.

classmethod Deserialize(process)

Deserialize an object’s state.

Objects cannot be deserialized directly, instead a Factory must be instructed to carry out the deserialization process.

Parameters:

process (DeserializationProcess) – The current stage of the deserialization process. This object is generated by the Factory and provides an interface to deserialization methods supporting multiple backends.

Return type:

Exponential

Returns:

The deserialized object.

serialize(process)

Serialize this object’s state.

Objects cannot be serialized directly, instead a Factory must be instructed to carry out the serialization process.

Parameters:

process (SerializationProcess) – The current stage of the serialization process. This object is generated by the Factory and provides an interface to serialization methods supporting multiple backends.

Return type:

None

property rms_delay: float

Root mean squared channel delay.

Returns: Delay in seconds.

property tap_interval: float

Tap interval.

Returns: Tap interval in seconds.