solve_ionosphere

ska_sdp_func_python.calibration.ionosphere_solvers.solve_ionosphere(vis: Visibility, modelvis: Visibility, xyz, cluster_id=None, zernike_limit=None, block_diagonal=False, niter=15, tol=1e-06)[source]

Solve for ionospheric delay as a function of station location.

Generate a gaintable by fitting for delta-TEC variations across the array. The resulting delta-TEC variations will be converted to antenna-dependent phase shifts and the gain_table updated.

Fits are performed within user-defined station clusters

Parameters:

  • vis – Visibility containing the observed data_model

  • modelvis – Visibility containing the predicted data_model

  • xyz – [n_antenna,3] array containing the antenna locations in the local horizontal frame

  • cluster_id – [n_antenna] array containing the cluster ID of each antenna. Defaults to a single cluster comprising all stations

  • zernike_limit – [n_cluster] list of Zernike index limits. Default is to leave unset when calling set_coeffs_and_params().

  • block_diagonal – If true, each cluster will be solved for separately during each iteration. This is equivalent to setting all elements of the normal matrix to zero except for the block diagonal elements for the cluster in question. (default False)

  • niter – Number of iterations (default 15)

  • tol – Iteration stops when the fractional change in the gain solution is below this tolerance.

Returns:

GainTable containing solutions