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 | ||||||||
(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 | |||||||||
the k-th code with minimum distance d produced by the lexicographic construction | is given in Figure 2.2 on page | ||||||||||
a| b | the concatenation of a and b | 111 | 010 = 111010 | |||||||||
ai | the concatenation of a with itself i times | (01)3 = 010101 | |||||||||
flexi, ftrelli, fstate, fdecoding | generating mappings for lexicodes, trellis-oriented codes, state-bounded codes, and decoding-bounded codes respectively | See Section 2.2 | |||||||||
G if, 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 using the generating mapping f ( . ) | is the linear code in Table 2.2 on page | |||||||||
d | the seed code {0d, 1d} for a particular generalized lexicographic construction | S3 = {000, 111} | |||||||||
R(v), | the rightmost and leftmost (respectively) significant bit of a bit sequence v = (v1, v2, v3,..., vn) | R(0101) = 4, | |||||||||
(l ) or (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 | (0101) = 0011 for code in Figure 1.1b (page ) | |||||||||
the binary complement of a | = 10101 | ||||||||||
nm, | 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 = 3 | |||||||||
T(H) | the Tanner graph corresponding to the parity-check matrix H | See Example 3.1 | |||||||||
() | the number of connected components in | For any tree, () = 1 | |||||||||
the Hamming weight (i.e. number of nonzero entries) of a matrix M | for the rank n identity matrix In | ||||||||||
n | the even-weight (n, n - 1, 2) code, whose parity-check matrixs consists of a single all-1 vector | 2 has vectors 00 and 11 | |||||||||
http://people.bu.edu/trachten