Design And Implementation Of Multi-mode MIMO-OFDM Communication System

The development of wireless communication has improved the communication rate and communication quality,but it has also caused the spectrum resources not to be used enough.At present,realizing high-speed and reliable communication has become a hot research topic in the case of limited frequency band resources.OFDM technology has high spectrum utilization rate and anti-frequency selective fading characteristics.MIMO technology can increase the reliability of the system through space diversity technology or double channel capacity through space multiplexing technology.The MIMO-OFDM technology which combines these two technologies has gradually become an important technology in the field of wireless communication.However,the computational complexity and hardware resource consumption are doubled when the communication rate increases.Thesis aims to realize multi-mode MIMO-OFDM communication system with multiple transmission and bandwidth modes on limited hardware resources.Thesis analyzes the architecture of a typical MIMO-OFDM communication system.It also explores and simulates the key technologies in the MIMO communication system.The system parameters are determined when the resource consumption and timing performance of different signal detection algorithms are compared.At last,the whole system is realized on the hardware platform.In thesis,the design analysis and performance simulation of synchronization algorithm,channel estimation and signal detection technology of MIMO-OFDM communication system are carried out.In the design of the MIMO signal detection algorithm,the performance simulation and complexity comparison of the zero-forcing algorithm,the minimum mean square error algorithm,the serial interference cancellation algorithm and the maximum likelihood estimation algorithm are focused on.And the bit error rate curves of the serial interference elimination algorithm and the maximum likelihood estimation algorithm are simulated under different transceivers and different bandwidth modes in this system.The multi-mode MIMO-OFDM system is implemented in hardware according to system parameters.Thesis explains the overall structure and functions of each module of the baseband transmitter and receiver.It compares the resource consumption and timing performance of the floating-point and fixed-point matrix inversion operations in the serial interference cancellation algorithm and analyzes the resource consumption and timing performance of the maximum likelihood estimation algorithm under different calculation methods and implementation structures.Considering the feasibility of resource consumption and the maximum transmission bandwidth of timing,the maximum likelihood estimation algorithm is finally selected as the signal detection algorithm of this system.Finally,the resource analysis and performance test of the realized multi-mode MIMO-OFDM communication system are carried out.The system is tested in the form of co-simulation of FPGA and MATLAB.Through the test,the communication link has good performance and meets the expected design requirements.