Patent ID: 7697616

Claim:
A method of modulating a digital signal of width L in frequency on a given useful frequency band comprising: separating the digital signal into N blocks b n (1≦n≦N), splitting the given useful frequency band into N contiguous parts P n , defining channels C n , of width l n in frequency such that their sum is equal to L, ∑ n = 1 N ⁢ ⁢ l n = L lying within an associated part P n , the channels C n being separated, and distributing each block of digital signals b n over the associated channel C n , wherein the channels C n are defined by taking account of a predetermined minimum distance between the channels to allow a predetermined maximum number of blocks to be affected by the phenomenon of flat fading, wherein the predetermined minimum distance between the channels is determined as a function of the number N of channels, of their width l n , and of a mean width of the frequency band affected by the phenomenon of flat fading so that the loss of information is not abrupt.