Kas. Immink, A PRACTICAL METHOD FOR APPROACHING THE CHANNEL CAPACITY OF CONSTRAINED CHANNELS, IEEE transactions on information theory, 43(5), 1997, pp. 1389-1399
Citations number
19
Categorie Soggetti
Information Science & Library Science","Engineering, Eletrical & Electronic
A new coding technique is proposed that translates user information in
to a constrained sequence using very long codewords, Huge error propag
ation resulting from the use of long codewords is avoided by reversing
the conventional hierarchy of the error control code and the constrai
ned code, The new technique is exemplified by focusing on (d, k)-const
rained codes, A storage-effective enumerative encoding scheme is propo
sed for translating user data into long dh sequences and vice versa. F
or dk runlength-limited codes, estimates are given of the relationship
between coding efficiency versus encoder and decoder complexity. We w
ill show that for most common d, k values, a code rate of less than 0.
5% below channel capacity can be obtained by using hardware mainly con
sisting of a ROM lookup table of size 1 kbyte. For selected values of
d and k, the size of the lookup table is much smaller, The paper is co
ncluded by an illustrative numerical example of a rate 256/466, (d = 2
, k = 15) code, which provides a serviceable 10% increase in rate with
respect to its traditional rate 1/2, (2,7) counterpart.