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komm.ExhaustiveSearchDecoder

Exhaustive search decoder for general block codes. This decoder implements a brute-force search over all possible codewords to find the one that is closest (in terms of Hamming distance, for hard-decision decoding, or Euclidean distance, for soft-decision decoding) to the received word.

Parameters:

  • code (BlockCode) –

    The block code to be used for decoding.

  • input_type (Literal['hard', 'soft']) –

    The type of the input. Either 'hard' or 'soft'. Default is 'hard'.

Notes
  • Input type: hard or soft.
  • Output type: hard.

__call__

Decode received words. This method takes one or more sequences of received words and returns their corresponding estimated message sequences.

Parameters:

  • input (ArrayLike) –

    The input sequence(s). Can be either a single sequence whose length is a multiple of $n$, or a multidimensional array where the last dimension is a multiple of $n$.

Returns:

  • output (NDArray[integer | floating]) –

    The output sequence(s). Has the same shape as the input, with the last dimension contracted from $bn$ to $bk$, where $b$ is a positive integer.

Examples:

>>> code = komm.HammingCode(3)
>>> decoder = komm.ExhaustiveSearchDecoder(code, input_type="hard")
>>> decoder([[1, 1, 0, 1, 0, 1, 1], [1, 0, 1, 1, 0, 0, 0]])
array([[1, 1, 0, 0],
       [1, 0, 1, 1]])

>>> code = komm.HammingCode(3)
>>> decoder = komm.ExhaustiveSearchDecoder(code, input_type="soft")
>>> decoder([[-1, -1, +1, -1, +1, -1, -1], [-1, +1, -1, -1, +1, +1, +1]])
array([[1, 1, 0, 0],
       [1, 0, 1, 1]])