Research On Decoding Algorithm And Implementation For Polar Code Based On 5G EMBB

Mobile communication technology has entered a new era of 5G,and as a potential coding scheme for 5G,polar code is attracting extensive attention and research.At present,polar code has been determined as the coding scheme for the control channel of eMBB scene.However,in the face of complex and variable communication requirements in the future,polar code is still very worth researching in coding structure and decoding algorithm.In particular,since the introduction of polar code in 2009,most research focuses on the theoretical level,as a result,there are relatively few studies in application level,which undoubtedly hinders the actual application of polar code.Several construction methods of polar code including density evolution,Gaussian approximation and polarization weighting adopted by 3GPP are introduced in this thesis firstly.Then the decoding algorithm is studied,including SC,BP,SCL and CA-SCL.Based on CA-SCL algorithm,an auxiliary decoding scheme is proposed called DCA-SCL,which can discretely distribute CRC bits among information bits by an interleaver.This scheme enables CRC bits to make auxiliary selection of surviving paths during SCL decoding.Finally,the requirements of the eMBB scene control channel in 3GPP and the implementation of the uplink polar code decoder are analyzed in this thesis.In terms of theoretical research,the DCA-SCL decoding algorithm proposed in this thesis can provide certain gain at low bit rate.At the code rate R=0.125,BLER=10^-3,the CRC length of 8 and 16 bits can provide 0.3dB and 0.9dB gain,respectively.The price is a certain complexity compared to CA-SCL.In terms of implementation research,overall implementation framework of polar code decoder in the eMBB scene uplink control channel is presented in this thesis,focusing on the implementation method of the core decoding and the CRC check module.