Research On Channel Estimation And Channel Equalization For MIMO-FBMC System

FBMC technology has attracted more and more attention because of its high spectrum utilization and low out-of-band attenuation.The MIMO-FBMC system,which combines MIMO technology with FBMC technology,can increase the throughput of the whole system and improve the transmission speed of wireless communication.It is considered as one of the alternatives for future mobile communication systems.So this paper focuses on the key technologies of MIMO-FBMC system,such as channel estimation and equalization.Firstly,the basic principle of FBMC system is expounded,and the inherent interference problem of FBMC system is analyzed.And simulating platforms of SISO and MIMO are built to compare and analyze the differences between FBMC and OFDM systems.Then the channel estimation technology of MIMO-FBMC system based on pilot is studied.Aiming at the design of pilot structure,the ICM and IAM pilot structures of SISO-FBMC system are analyzed at first.ICM-K and ICM-H structures are analyzed in ICM.And IAM-R,IAM-C and E-IAM-C structures are analyzed in IAM.Next,the MIAM pilot structure and the pilot structure to reduce pilot overhead in MIMO-FBMC system are studied,and then their performance is simulated and analyzed.In the aspect of channel estimation algorithm,this paper first analyses the advantages and disadvantages of traditional channel estimation algorithm,and then proposes an improved algorithm based on SVD.Firstly,the algorithm uses power detection and reverse search to get the effective time-domain estimation result of channel.Then,the eigenvalues of SVD algorithm are intercepted by the order of the result,the simulations on ITU PA and ITU VA multipath fading models show the superiority of the proposed algorithm in different mobile environments.Finally,the channel equalization algorithm of MIMO-FBMC system is studied.Aiming at the problem that traditional channel equalization algorithm can not be well applied to MIMO-FBMC system,this paper first establishes a mathematical model of channel equalization of MIMO-FBMC system and studies the characteristics of signal transmission.Then,a channel equalization algorithm based on SINR is proposed,which takes SINR as the objective function and maximizes it to obtain the optimal equalizer.Finally,the simulation results show that in the MIMO-FBMC system which combines the improved SVD algorithm proposed in this paper,the algorithm not only has good performance in low-speed mobile scenarios,but also applies to high-speed mobile scenarios,reflecting strong robustness and stability.