Resumen
The codewords of a low-density parity-check (LDPC) convolutional code (LDPC-CC) are characterised into structured and non-structured. The number of the structured codewords is dominated by the size of the polynomial syndrome former matrix ????(??)
H
T
(
D
)
, while the number of the non-structured ones depends on the particular monomials or polynomials in ????(??)
H
T
(
D
)
. By evaluating the relationship of the codewords between the mother code and its super codes, the low weight non-structured codewords in the super codes can be eliminated by appropriately choosing the monomials or polynomials in ????(??)
H
T
(
D
)
, resulting in improved distance spectrum of the mother code.