A method for polar code rate matching in a communication device, comprising: determining whether to puncture or shorten a mother polar code according to a mother code rate and a rate matched code rate in order to fit a to-be-transmitted code bits length M, wherein the mother code rate is a ratio of the information bits length K to the mother polar code length N, and the rate matched code rate is a ratio of the information bits length K to the to-be-transmitted code bits length M, the mother polar code including a sequence of N code bits to-be-generated from a polar encoder that encodes a sequence of N input bits to generate the mother polar code, each input bit corresponding to a synthesized channel having a reliability for transmitting the respective input bit over the synthesized channel, each input bit and respective synthesized channel corresponding to an index; determining whether to puncture or shorten the mother polar code according to the mother code rate and the rate matched code rate including: determining to puncture the mother polar code when the mother code rate is smaller than a first threshold rate and the rate matched code rate is smaller than a second threshold rate; and determining to shorten the mother polar code when the mother code rate is larger than the first threshold rate or the rate matched code rate is larger than the second threshold rate; and selecting K positions in the sequence of N input bits for input of K information bits to the polar encoder according to a predetermined index list that is ordered according to the reliabilities of the N synthesized channels, wherein the K positions correspond to K synthesize channels having the highest reliabilities among the N synthesized channels excluding synthesized channels of frozen input bits determined according to punctured code bits or shortened code bits. determining whether to puncture or shorten a mother polar code according to a mother code rate and a rate matched code rate in order to fit a to-be-transmitted code bits length M, wherein the mother code rate is a ratio of the information bits length K to the mother polar code length N, and the rate matched code rate is a ratio of the information bits length K to the to-be-transmitted code bits length M, the mother polar code including a sequence of N code bits to-be-generated from a polar encoder that encodes a sequence of N input bits to generate the mother polar code, each input bit corresponding to a synthesized channel having a reliability for transmitting the respective input bit over the synthesized channel, each input bit and respective synthesized channel corresponding to an index; determining whether to puncture or shorten the mother polar code according to the mother code rate and the rate matched code rate including: determining to puncture the mother polar code when the mother code rate is smaller than a first threshold rate and the rate matched code rate is smaller than a second threshold rate; and determining to shorten the mother polar code when the mother code rate is larger than the first threshold rate or the rate matched code rate is larger than the second threshold rate; and determining to puncture the mother polar code when the mother code rate is smaller than a first threshold rate and the rate matched code rate is smaller than a second threshold rate; and determining to shorten the mother polar code when the mother code rate is larger than the first threshold rate or the rate matched code rate is larger than the second threshold rate; and selecting K positions in the sequence of N input bits for input of K information bits to the polar encoder according to a predetermined index list that is ordered according to the reliabilities of the N synthesized channels, wherein the K positions correspond to K synthesize channels having the highest reliabilities among the N synthesized channels excluding synthesized channels of frozen input bits determined according to punctured code bits or shortened code bits.