Research And Implementation Of Signal Detection For Physical Downlink Shared Channel In 5G System

5G,as a new generation of mobile communication system,has wider application scenarios and attracts widespread attention at home and abroad.In order to meet the requirements of the National Science and Technology Major Project “Enhanced the Research and Development of Mobile Broadband 5G Terminal Simulators”,the Physical Downlink Shared Channel(PDSCH)of 5G is studied.Especially,the design,development and implementation of the signal detection module are focused.The main work and innovation are as follows.Massive MIMO is one of the key technologies of 5G.Because of the large number of antennas,traditional signal detection cannot meet the performance requirements and complexity requirements.In order to find the balance between performance and complexity,the signal detection algorithm based on shadow domain is proposed.At the same time,an approximate pruning strategy based on the objective function is proposed for reducing the complexity.When the Antenna scale is 32 ? 32,the modulation order is 6,the branch strategy of the proposed algorithm is same as BB and the bit error rate achieves 10-4,the simulation results show that the BER performance of the proposed algorithm is ensured and the complexity of the proposed algorithm is reduced by 88.97% compared with BB.In order to decrease complexity with ensuring performance,because the criteria for selecting the optimal neighborhood vector is consider ed in the neighborhood search algorithm,a branching strategy based on neighborhood search is proposed.When the Antenna scale is 32 ? 32,the modulation order is 4 and the bit error rate achieves 10-5,the simulation results show that the performance of the proposed algorithm is ensured and the complexity of the proposed algorithm is reduced by 69.84% compared with BB.At the receiving end of PDSCH,the complexity of detection is lower,the delay is smaller.And the performance of detection is better,the overall block error rate is smaller.Since PDSCH supports multiple modulation orders,the proposed algorithms are combined with existing algorithms,and then the transmitting and the receiving link simulation processes of PDSCH are established.The performance and complexity advantages of the proposed signal detection scheme are analyzed.Regardless of the modulation order,the simulation results show that the received information can be correctly obtained on lower signal-to-noise ratio.In order to meet the needs of project,the transmitting and the receiving processes of PDSCH are implemented in C language on the DSP platform,and then the performance and cycle of the proposed detection scheme are tested.The results show that the performance error of DSP implementation is between 0.43% and 1.71% compared with MATLAB simulation,but this error range is acceptable to the project.In addition,the total running clock cycle of each module is within 0.5ms,so the slot requirements of PDSCH are met.Therefore,the proposed signal detection scheme can meet the delay and performance requirements of the project.