A method of optimizing the size of blocks of coded data, intended to be subjected
to iterative decoding, the method comprising a first step of evaluating a resource
(T) available for the decoding of a block of normal size (N) and a second step
of seeking, amongst a plurality of block sizes (N/k) which are submultiples of
the normal size by an integer factor (k) greater than or equal to 1 and requiring
on average a number of iterations ({overscore (n)}iterations(k))
compatible with the said available resource, the one which makes it possible to
obtain the lowest error rate at the output of the iterative decoding.