optic.comm.modulation.softMapper

softMapper(llr, M, constType, prec=<class 'numpy.float32'>)

Soft mapper for Gray-mapped modulation formats.

Parameters:

• llr (1D numpy array) – Log-likelihood ratios (LLRs) of bits.

• M (int) – Modulation order.

• constType (str) – Type of constellation (‘qam’, ‘psk’, ‘pam’, ‘apsk’, or ‘ook’).

• prec (data type, optional) – Precision of the output (default is np.float32).

Returns:

• - softMean (1D numpy array) – Soft mean of the constellation symbols.

• - softVar (1D numpy array) – Soft variance of the constellation symbols.