WE CLAIM:
[Claim 1]
A method for configuring a Divide and Conquer structure of a polar-code based encoder performing a transfer of useful data to a polar-code based decoder via a Binary Discrete-input Memory-less Channel, the method being performed by the polar-code based encoder, the Divide and Conquer structure consisting of a multiplexer followed by a polarization block of size N = 2L, the multiplexer having useful data bits and a set of frozen bits as inputs so as to
form input data x^.N ,
wherein the polarization block of size N comprises a set of front kernels followed by a shuffler and two complementary polarization sub-blocks of size N/2 with a similar structure as the polarization block of size N but with half its size, wherein the shuffler distributes its odd entries to one of the complementary polarization sub-blocks and its even entries to the other one of the complementary polarization sub-blocks, such that the Divide and Conquer structure is recursive with a depth equal to L,
characterized in that a dynamically configurable interleaver is present between the shuffler and one and/or the other of the complementary polarization sub-blocks at each recursion of the Divide and Conquer structure,
and in that the method comprises:
- detecting change in the Binary Discrete-input Memory-less Channel;
- obtaining probability functions p^™ , which characterize channel transitions probabilities of the Binary Discrete-input Memory-less Channel at output of the polarization block of size N, according to the detected change in the Binary Discrete-input Memory-less Channel;
-computing probability functions p\™ , which characterize channel transitions probabilities of an equivalent Binary Discrete-input Memory-less Channel at input of the polarization block of size N, from the obtained probability functions p^™ for a set of interleaving configurations of the dynamically configurable interleavers, determining corresponding positions of the frozen bits and determining a corresponding figure of merit value, wherein
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the figure of merit is an estimation representative of performance of the transfer to the polar-code based decoder via the Binary Discrete-input Memory-less Channel; and
- selecting and applying the interleaving configuration of the dynamically configurable interleavers which shows the best performance of the transfer to the polar-code based decoder via the Binary Discrete-input Memory-less Channel in view of the determined corresponding figure of merit values. [Claim 2]
The method according to claim 1, characterized in that the figure of merit is mutual information-based and is defined as follows:
XT' lf (in) , (in) %
2^ l(x) ^y|*i\y_i)
0