Simulation Backend Selection

Supported backends and defaults

Use InterferometerSimulation.run_simulation(...) with a SimulatorBackend enum value:

• SimulatorBackend.SDP (value "ska-sdp") selects the Karabo-native SKA-SDP simulation path.

• SimulatorBackend.OSKAR (value "OSKAR") selects OSKAR simulation and its telescope and beam options.

The default is OSKAR for both run_simulation and Telescope.constructor. Pass the backend explicitly, and construct a telescope for that backend. A regular Observation returns a Karabo Visibility; an OSKAR ObservationParallelized returns a list of visibility products.

Selecting SDP

Given a Karabo sky and observation:

from karabo.simulator_backend import SimulatorBackend
from karabo.simulation.interferometer import InterferometerSimulation
from karabo.simulation.telescope import Telescope

telescope = Telescope.constructor("MID", backend=SimulatorBackend.SDP)
simulation = InterferometerSimulation()
vis = simulation.run_simulation(
    telescope=telescope,
    sky=sky,
    observation=observation,
    backend=SimulatorBackend.SDP,
    visibility_format="MS",
)

SDP writes Measurement Sets and can apply a custom SDP image supplied through primary_beam. Sky-model conversion uses SKA-SDP sky components internally. The Examples page links an end-to-end SDP line-emission notebook.

Selecting OSKAR

Use an OSKAR telescope configuration and select OSKAR in the same entry point:

telescope = Telescope.constructor("EXAMPLE", backend=SimulatorBackend.OSKAR)
vis = simulation.run_simulation(
    telescope=telescope,
    sky=sky,
    observation=observation,
    backend=SimulatorBackend.OSKAR,
    visibility_format="MS",
)

Configure OSKAR beam behavior through InterferometerSimulation constructor parameters. A custom primary_beam passed to run_simulation is ignored with a warning for OSKAR.

Imaging the result

Use Measurement Set output for either Imaging Backend Selection backend. The simulation backend does not determine which imager you must use.

For cross-simulator frequency comparisons, check the output frequency metadata: OSKAR uses the configured start frequency for the first channel, while SDP uses the channel centre (start frequency plus half the channel width).

For removed selectors and older telescope-construction patterns, see Migrating from RASCIL.