A method of decoding a data signal includes progressively constructing a decoding tree, implementing at least two iterations of the following steps: selecting at least one child node of a current node belonging to a selection interval; storing the child nodes in a first stack; deleting the current node from the first stack; selecting a new current node from the first stack; and if the new current node is a leaf node, storing the path between the root node and the leaf node, in the second stack, and deleting the leaf node from the first stack; otherwise, return to the step of selecting a child node for the new current node. Moreover, the method assigns a probability of likelihood to the bits of at least one symbol of the data signal, taking account of the paths stored in the second stack, and determines a probabilistic estimation of the signal.