A method to explicitly indicate the version information while still supporting soft combining is disclosed. A polar code encoder maps q bits to q positions of q sub-channels, q is a positive integer; wherein the q bits are used to indicate a version of encoded codeword; map 1 to a special frozen bit corresponding to the q bits; map K−q information bits to K−q positions for the K−q information bits, K is an integer, K>q; and perform polar encoding over an input vector u0N-1, comprising the q bits, the special frozen bit and the K−q information bits, with the length of N, N is an integer, N>=K. With this method, there is no need to make blind detection to achieve the version information of transmitted payload, which reduces power consumption for a receiver.