Design and Implementation of a 5G NR System Based on LDPC in Open Source SDR

Low-density parity-check (LDPC) code has been chosen as the coding scheme for data channels in enhance Mobile Broad Band (eMBB) of the fifth generation (5G) New Radio (NR) technical specifications. However, there has not been a low-cost and flexible platform to evaluate the performance of LDPC over the air interface now. In this paper, the Physical Downlink Shared Channel (PDSCH) encoder and decoder are first realized on the OpenAirInterface (OAI) DLSIM platform to validate the LDPC code. Then, in order to meet the real-time requirements of Software Defined Radio (SDR) system, the extended instruction set and multithreading are used to optimize LDPC encoder and decoder. Based on our proposed system, plenty of experiments are carried out to evaluate the LDPC performances not only by simulations but also through the field trials over the air. The results demonstrate that 5G NR system based on LDPC has excellent performance in terms of the throughput.