Notation

Introduced Expression Denotes Example
Page [*] [n, M, d] code a code with length n containing M vectors of minimum Hamming distance d from each other See Figure 1.1a on page [*]

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(n, k, d ) code a linear code of length n representing a k dimensional subspace of vectors with minimum Hamming distance d from each other See Figure 1.1b on page [*]

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$\ensuremath{\mathcal{L}_{k}^{d}}$ the k-th code with minimum distance d produced by the lexicographic construction $\ensuremath{\mathcal{L}_{4}}^3$ is given in Figure 2.2 on page [*]

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$ \langle$a| b$ \rangle$ the concatenation of a and b $ \langle$111  |  010$ \rangle$ = 111010

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ai the concatenation of a with itself i times (01)3 = 010101

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flexi, ftrelli, fstate, fdecoding generating mappings for lexicodes, trellis-oriented codes, state-bounded codes, and decoding-bounded codes respectively See Section 2.2

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G i$ \left(\vphantom{ f,\mathbb{C} }\right.$f,$ \mathbb {C}$$ \left.\vphantom{ f,\mathbb{C} }\right)$ or G i or G the Generalized Lexicographic Construction; if arguments are supplied, they refer to the i-th iteration of the construction seeded by code $ \mathbb {C}$ using the generating mapping f ( . ) ${\mathfrak{G}}_{\,3} \left( \ensuremath{f_{\mbox{\small lexi}}},\mathbb{S}_3 \right)$ is the linear code in Table 2.2 on page [*]

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$ \mathbb {S}$dthe seed code {0d, 1d} for a particular generalized lexicographic construction S3 = {000, 111}

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R(v), $\ensuremath{\operatorname{L}}(v)$ the rightmost and leftmost (respectively) significant bit of a bit sequence v = (v1, v2, v3,..., vn) R(0101) = 4, $\ensuremath{\operatorname{L}}(0101)=2$

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$ \kappa_{v}^{}$(l ) or $ \kappa$(l ) the companion of coset leader l under v; i.e. the coset leader of the coset containing l + v; v is omitted in context $ \kappa_{{0110}}^{}$(0101) = 0011 for code $ \mathbb {C}$ in Figure 1.1b (page [*])

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$ \bar{{a}}$ the binary complement of a $ \overline{{01010}}$ = 10101

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nm, $ \rho_{m}^{}$ the length and covering radius (respectively) of k-th code in a G-family the (7, 3, 4) lexicode has length n3=7 and covering radius $ \rho_{3}^{}$ = 3

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T(H)the Tanner graph corresponding to the parity-check matrix H See Example 3.1

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$ \omega$($ \cal {G}$)the number of connected components in $ \cal {G}$For any tree, $ \omega$($ \cal {G}$) = 1

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$\ensuremath{\operatorname{wt}}(M)$the Hamming weight (i.e. number of nonzero entries) of a matrix M $\ensuremath{\operatorname{wt}}(I_n)=n$ for the rank n identity matrix In

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$ \cal {E}$nthe even-weight (n, n - 1, 2) code, whose parity-check matrixs consists of a single all-1 vector $ \cal {E}$2 has vectors 00 and 11

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