Research On Polar Codes And Performance Evaluation In Short Frame Communication

Channel coding is one of the most important technologies in the fifth generation mobile communication systems,which can significantly improve the communication reliability.Therefore,construction of code sequences with excellent error correction performance and low encoding/decoding complexities has always been the purpose of channel coding.It is also the key to meet the increasing requirements of future mobile communication systems.Polar codes,proposed by Erdal Arikan in 2009,are the first coding schemes that provably achieve the Shannon capacity of memoryless symmetric channels with an explicit construction based on the channel polarization.Furthermore,both cyclic redundancy check(CRC)-concatenated polar codes and parity-check-concatenated(PCC)polar codes exhibit remarkable error correction performance.Thus,polar codes are very promising in future mobile communication systems.However,the code length of conventional polar codes is limited to be 2n(n=1,2,…).It does not adapt the actual communication scenes with arbitrary code length,which could be solved by puncturing.So it is necessary to design an appropriate puncturing pattern for polar codes.Firstly,this paper analyzes two construction methods of punctured polar codes.The first method is Monte-Carlo method based on the successive cancellation(SC)decoding algorithm.The second one is based on the reliability sequence,which is adopted for constructing punctured polar codes in this paper because of the high efficiency and flexibility.Secondly,we propose the sub-polar puncturing scheme based on the recursive structure of the generator matrix,because the combination of quasi-uniform puncturing(QUP)scheme and the reliability sequence is not excellent.By the proposed puncturing scheme,the punctured positions are corresponding to the sub-matrices of the generator matrix,which reduces the influence of puncturing on the code structure as much as possible.Finally,the performance of sub-polar puncturing scheme is demonstrated by simulation.In addition,the performance of QUP scheme is presented for comparison.Simulation results show that the proposed puncturing scheme could produce better error correction performance based on the reliability sequence than QUP scheme.