Research On Key Technology Of Ultra-High-Speed Mimo Transmission System Receiver

The development of communication theory and the innovation of electronic technology have brought great changes to people’s way of life.Meanwhile,people have a higher and higher demand for data transmission rate.MIMO technology can achieve high system capacity in limited bandwidth,which is the core technology to achieve high-speed transmission.In this era of information explosion,the research on the key technology of ultra-high-speed MIMO receiver is of great significance both in theory and practical application.In this paper,the baseband transmission scheme of 8×8 MIMO system under 200MHz bandwidth is designed.Moreover,the channel coding technology and compensation of system non-ideal characteristics are studied.On this basis,the hardware implementation platform is built to verify the system scheme and the effective transmission rate can reach 10Gbps in the indoor environment.Firstly,the research background and significance of the topic are introduced.Then,the basic principle of MIMO system,channel coding and non-ideal characteristics of the system are summarized.On this basis,the baseband design scheme of ultra-high-speed MIMO transmission system is given,including frame structure,physical layer parameter and overall architecture.The key algorithms of receiver with low complexity including timing synchronization,signal estimation and detection and QAM soft demodulation are also introduced.Secondly,low density parity check（LDPC）codes are investigated.The implementation complexity of various coding algorithms is analyzed at first.And then,the BP decoding algorithm and the simplified MS and NMS decoding algorithm derived from it are investigated.Based on NMS algorithm,the overall design scheme of 5G LDPC decoder with partial parallel structure is presented.Each key module of the decoder is introduced in detail.Finally,the performance of the decoder is simulated and analyzed,and the results show that the decoder can achieve the throughput of 1.1Gbps.For the non-ideal factors of communication system,carrier frequency offset and IQ imbalance are mainly investigated.The influence of these two non-ideal factors on the performance of ultra-high-speed transmission system is analyzed and the synchronization sequence design is given.Then,carrier synchronization scheme and residual frequency offset tracking scheme are given.Considering the existence of these two non-ideal factors simultaneously,a joint estimation and compensation method is proposed.Simulation results show that the non-ideal feature compensation scheme proposed in this chapter has low computational complexity and excellent performance,and is suitable for use in practical systems.On the basis of the above,this paper studies the hardware implementation scheme of ultra-high-speed MIMO transmission transceiver.The implementation structure and results of frequency offset estimation,residual frequency offset tracking and LDPC decoder are given.Finally,a hardware verification platform was built in an indoor environment to test the real-time transmission of 8×8MIMO.The test results show that the effective transmission rate can reach 10 Gbps and the bit error rate can reach magnitude of10^-8.