Simulated Devices

class SimulatedDevice(scenario=None, rf_chain=None, adc=None, sampling_rate=None, carrier_frequency=0.0, *args, **kwargs)

Bases: hermespy.core.device.Device, hermespy.core.random_node.RandomNode, hermespy.core.factory.Serializable

Representation of a device simulating hardware.

Simulated devices are required to attach to a scenario in order to simulate proper channel propagation.

Warning

When configuring simulated devices within simulation scenarios, channel models may ignore spatial properties such as position(), orientation() or velocity().

Parameters

  • scenario (Scenario, optional) – Scenario this device is attached to. By default, the device is considered floating.

  • rf_chain (RfChain, optional) – Model of the device’s radio frequency amplification chain.

  • adc (AnalogDigitalConverter, optional) – Model of receiver’s ADC converter.

  • sampling_rate (float, optional) – Sampling rate at which this device operates. By default, the sampling rate of the first operator is assumed.

  • carrier_frequency (float, optional) – Center frequency of the mixed signal in rf-band in Hz. Zero by default.

  • *args – Device base class initialization parameters.

  • **kwargs – Device base class initialization parameters.

yaml_tag: Optional[str] = 'SimulatedDevice'

YAML serialization tag.

rf_chain: RfChain

Model of the device’s radio-frequency chain.

adc: AnalogDigitalConverter

Model of receiver’s ADC

property orientation: numpy.ndarray

Orientation of the device within its scenario as a quaternion.

Returns

The modem orientation as a normalized quaternion. None if the position is considered to be unknown.

Return type

orientation (Optional[np.array])

Raises

ValueError – If orientation is not a valid quaternion.

property scenario: hermespy.core.scenario.Scenario

Scenario this device is attached to.

Returns

Handle to the scenario this device is attached to.

Return type

Scenario

Raises

  • FloatingError – If the device is currently floating.

  • RuntimeError – Trying to overwrite the scenario of an already attached device.

property topology: numpy.ndarray

Antenna array topology.

The topology is represented by an Mx3 numpy array, where the first dimension M is the number of antennas and the second dimension their cartesian position within the device’s local coordinate system.

Returns

A matrix of Mx3 entries describing the sensor array topology.

Return type

topology (np.ndarray)

Raises

ValueError – If the first dimension topology is smaller than 1 or its second dimension is larger than 3.

property attached: bool

Attachment state of this device.

Returns

True if the device is currently attached, False otherwise.

Return type

bool

property noise: hermespy.simulation.noise.noise.Noise

Model of the hardware noise.

Returns

Handle to the noise model.

Return type

Noise

property sampling_rate: float

Sampling rate at which the device’s analog-to-digital converters operate.

Returns

Sampling rate in Hz.

Return type

sampling_rate (float)

Raises

  • ValueError – If the sampling rate is not greater than zero.

  • RuntimeError – If the sampling rate could not be inferred.

property carrier_frequency: float

Central frequency of the device’s emissions in the RF-band.

Returns

Carrier frequency in Hz.

Return type

frequency (float)

Raises

ValueError – On negative carrier frequencies.

property velocity: numpy.ndarray

Cartesian device velocity vector.

Returns

Velocity vector.

Return type

np.ndarray

Raises

  • ValueError – If velocity is not three-dimensional.

  • NotImplementedError – If velocity is unknown.

property operator_separation: bool

Separate operators during signal modeling.

Return type

bool

Returns

Enabled flag.

transmit(clear_cache=True)

Transmit signal over this device.

Parameters

clear_cache (bool, optional) – Clear the cache of operator signals to be transmitted. Enabled by default.

Returns

Signal emitted by this device.

Return type

Signal

property snr: float

Signal to noise ratio at the receiver side.

Return type

float

Returns

Linear ratio of signal to noise power.

receive(device_signals, snr=None, snr_type=SNRType.EBN0)

Receive signals at this device.

Parameters

  • device_signals (Union[List[Signal], np.ndarray]) – List of signal models arriving at the device. May also be a two-dimensional numpy object array where the first dimension indicates the link and the second dimension contains the transmitted signal as the first element and the link channel as the second element.

  • snr (float, optional) – Signal to noise power ratio. Infinite by default, meaning no noise will be added to the received signals.

  • snr_type (SNRType, optional) – Type of signal to noise ratio.

Returns

Baseband signal sampled after hardware-modeling.

Return type

baseband_signal (Signal)

classmethod to_yaml(representer, node)

Serialize a SimulatedDevice object to YAML.

Parameters

  • representer (SimulatedDevice) – A handle to a representer used to generate valid YAML code. The representer gets passed down the serialization tree to each node.

  • node (SimulatedDevice) – The Device instance to be serialized.

Returns

The serialized YAML node.

Return type

MappingNode

classmethod from_yaml(constructor, node)

Recall a new SimulatedDevice class instance from YAML.

Parameters

  • constructor (SafeConstructor) – A handle to the constructor extracting the YAML information.

  • node (MappingNode) – YAML node representing the SimulatedDevice serialization.

Returns

Newly created serializable instance.

Return type

SimulatedDevice