Research And Implement Of 5G NR Physical Layer Uplink Shared Channel

The 5th Generation(5G)mobile communication system has attracted wide attention at home and abroad due to its more diversified application scenarios,higher transmission rate,higher flexibility,reliability,and low delay characteristics.Among them,the 5G New Radio(NR)Physical Uplink Shared Channel(PUSCH)is used to carry uplink user data information and multiplexed control information,which is an important guarantee for maintaining normal 5G communication.Relying on the research and development requirements of the "5G baseband signal demodulation and decoding equipment" project,this thesis conducts the research and implementation of the physical layer uplink shared channel in the 5G system.The main work and innovations are as follows:1.Study the 5G physical uplink shared channel.Based on the 5G NR Rel-15 version of the physical layer related protocol,the PUSCH sender process was researched and analyzed,and the PUSCH receiving processing process was designed,and the PUSCH simulation link was built to verify.The entire PUSCH link can correctly complete the demodulation and decoding process of the received information,indicating that the design is reasonable and effective.2.The Low Density Parity Check(LDPC)coding scheme introduced by 5G PUSCH is analyzed,and the relevant LDPC decoding algorithm is focused on.In order to solve the optimization problem between LDPC decoding complexity and decoding performance,based on the LDPC Offset Min-Sum(OMS)decoding algorithm,Based Variable Node Message Weighted and Density Evolution Offset Min Sum Decoding algorithm(VWDEOMS)is proposed.The algorithm introduces Density Evolution theory to optimize the traditional offset factors,uses linear approximation methods to optimize the high computational complexity problems caused by the introduction of Density Evolution,At the same time,combined with the weighted average method,the oscillation phenomenon of variable node update in LDPC decoding algorithm is improved,and the decoding convergence is improved,and the VWDEOMS algorithm is used in the PUSCH receiving link.The improved decoding algorithm proposed in this thesis increases the decoding performance by about 0.3d B compared to the traditional OMS decoding algorithm with a small increase in computational complexity,and the average number of iterations is reduced by about 24.3%.It is also suitable for different5 G coding rates and Modulation.3.Combining the improved decoding algorithm proposed in this thesis with the research and design of PUSCH link,the TMS320C6678 DSP chip is used to realize the PUSCH transmission and reception processing flow,and the modular principle is adopted to determine the performance of the LDPC decoding module and each module Perform statistical analysis on the operating clock cycle.The simulation results show that the proposed improved decoding algorithm reduces the decoding delay by 10.3%compared with the OMS algorithm,the gain range of the decoding performance is0.1-0.2d B,and the total running time of the DSP implementation of the PUSCH link is0.3663 ms,in a time slot Meet project requirements within the scope.