Design And Implementation Of Baseband Signal Processing Algorithm In MIMO-OFDM Communcation Systems

Wireless communication brings great convenience to our life,making it easier to transfer information between people.With the development of wireless communication,all walks of life have begun to combine their industry with wireless communication.Nowadays,the demand for communication services in various industries is no longer a single voice-service,but also text,images,video and other services,and the requirements for quality of communication have also been increasing.It makes wireless communication systems capable of carrying more information and having higher data transmission rates.Based on the practical application requirements of wireless communication system,this thesis will design a baseband signal processing scheme for large-capacity,high-data-rate wireless communication system and implement it on the FPGA.The main contents include the following aspects:(1)According to the requirement of wireless communication engineering design,this thesis analyzes design requirements and index of baseband signal processing system,and designs a baseband signal processing scheme for a wireless communication system based on MIMO-OFDM technology to improve the system capacity and data transmission rate,because OFDM technology has the advantage of high spectrum utilization is orthogonality between subcarriers,and MIMO technology increases the number of antennas on the basis of increasing the number of antennas without increasing the frequency bandwidth.Simulation results of system-related parameters validate the theoretical feasibility of the system and provides a theoretical basis for hardware implementation.(2)Synchronization is the primary problem in the receiver of the wireless communication system.Aiming at the problem of synchronization deviation when the first path is not the strongest path,a synchronization scheme based on channel estimation is designed to correct the synchronization.Combined with simulation results,while taking the system performance into account,in order to reduce the resource occupancy rate when scheme is implemented on the hardware,the extracted data is used as the synchronization data;(3)In order to ensure the correct demodulation of the data,the thesis studied the channel estimation algorithm.Taking the performance,cost and complexity,and the simulation results into account,the data-aided channel estimation scheme based on Alamouti coding is adopted,so the system overhead and the hardware implementation complexity are reduced;For the purpose of recovering the actual signal from the mixed signal,the thesis studied the signal detection algorithm.Guaranteeing the performance of the system and considering the simulation results,the zero forcing signal detection algorithm is adopted based on the principle of low complexity and feasibility.(4)Based on the previous key technology research,the specific method of hardware implementation was given,and the implementation of the baseband signal processing scheme of the broadband wireless communication system was completed on the FPGA.The feasibility of the scheme designed by the thesis is demonstrated through hardware implementation,the performance of the baseband signal processing system was tested on the hardware platform in the actual communication environment.The test results show that the system function is correct,and the system can work stably and reliably.Compared with the traditional OFDM system,the data transmission rate is double,which provides guarantee for the practical application of the design scheme.