Construction of a polar code based on a distance criterion and a reliability criterion, in particular of a multi-kernel polar code

The present invention relates to a device (102b, 104b) for generating a polar code ϰ N of length N and dimension K on the basis of a transformation matrix G N of size N x N, wherein the transformation matrix G N is based on a first matrix G N r of size N r x N r , and on a second matrix G Nd of size N d x N d , wherein N = N r ⋅ N d, and wherein the polar code ϰ N is given by ϰ N = υ N ⋅ G N , wherein υ N = (υ0,..., υ N -1)is a vector of size N, υ i ,i = 0,... N−1, corresponding to an information bit if i ε I, I being a set of K information bit indices, and υ i = 0, if i ε F, F being a set of N − K frozen bit indices. The device (102b, 104b) comprises a processor (102c, 104c) configured to generate a reliability vector v GNr = [v1,... v Nr ], wherein v i represents a reliability of an i-th input bit of a code generated by the first matrix G Nr , generate a distance spectrum vector d GNd = [d1,..., d Nd ] of a code generated by the second matrix G Nd , wherein d j represents a minimum distance of the code generated by the second matrix G Nd of dimension j, determine the set of K information bit indices I on the basis of the reliability vector v GNr and of the distance spectrum vector d GN , and generate the polar code c N on the basis of the set of K information bit indices I.