Patent ID: 6690736
Filing Date: 2004-02-10
Classification: H04L

Abstract:
A method for allocating bits to carriers in a multicarrier or discrete multi tone (DMT) modulated transmission system, wherein a number of carriers N and a number of bits B are limited, the former due to useable frequency band and carrier spacing and the latter due to bit rate and block size, comprising the steps of:(i) associating a quality factor lj to each carrier j, j=1, . . . , N, (ii) computing a loading constant Lc as the quotient of a difference and the number of carriers Nr that remain to get bits allocated, said difference being the difference of the sum of the quality factors lk for carriers k, k=1, . . . , Nr, that remain to get bits allocated and the total number of data bits nr that remain to be allocated, (iii) allocating a number of bits nito a carrier i that remains to get bits allocated, said number of bits nl being the difference of the quality factor ll and the loading constant Lc rounded to nearest integer, (iv) repeating the step of allocating until a predetermined fraction of the carriers k, k=1, . . . , Nr, have bits allocated, and (v) repeating the steps (ii)-(iv) until all carriers j have bits allocated.