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s_to_y_matrix

s_to_y_matrix(s_matrix, impedances=50.0)

Convert an S-matrix (scattering matrix) to a Y-matrix (admittance matrix).

Uses the travelling-wave S-parameter convention (inverse of y_to_s_matrix).

This is a direct conversion (more efficient than S→Z→Y).

Note

The |v_0|/v_0 phase correction factor from the full travelling-wave definition is omitted. This is exact for lossless reference media and an excellent approximation for low-loss ports.

Args

  • s_matrix (SMatrix): The scattering matrix to convert.
  • impedances (complex | float | dict[str, complex | float]): Reference impedance(s). If a single number, all terminals use the same impedance. If a dict, maps terminal names to their reference impedances. Defaults to 50.0.

Returns

YMatrix: The converted admittance matrix.