Massive MIMO-FBMC Pilot-based Channel Estimation And Precoding Iterative Design

With the wisdom of the city,intelligent driving and industrial 4.0 era proposed,a world in which all interconnected is yet to come,access to information anytime and anywhere,perceived context,intelligent interaction,virtual reality,true telemedicine will become a reality.However,for the existing communication technology,it is far from being able to meet these future communication scenarios for low power consumption,high speed,high capacity and mobile access low latency.So 5G must be debut in advance.In the studies of recent years,as a future 5G candidate technology,the multi-carrier technology(FBMC)applied to Massive MIMO has gradually become a new research hotspot,In this paper,the channel estimation of large-scale MIMO-FBMC system,the pilot energy efficiency in channel estimation and the design of downlink precoder has been in-depth explored and researched.The following is the main research work of this paper:Firstly,this paper studies the main sources of the imaginary interference in the channel of the Massive MIMO-FBMC system,analyzes the distribution characteristics of the imaginary part interference and proposes a channel estimation scheme based on the discrete pilot.The scheme considers the division of the imaginary part of the pilot.For different interference regions,the interference control is effectively implemented by using different interference cancellation strategies,which reduces the interference of the imaginary parts of the pilot and improves the reliability of transmission of Massive MIMO-FBMC system.Secondly,the problem of pilot energy efficiency in the channel estimation scheme is analyzed,the relationship between pilot energy efficiency and channel estimation performance is studied.The pilot power efficiency and channel estimation performance are combined to optimize the design,Simulation shows that under the premise of satisfying the channel estimation performance,the additional power consumption of the pilot in the channel estimation process is reduced,and the energy efficiency of the pilot in the large-scale MIMO-FBMC system is greatly improved,balanced the two needs of the performance well.Finally,a system model of multi-user Massive MIMO-FBMC under frequency selective channel is given,based on this,the problems of downlink channel precoding and equalizer design are discussed.A precoding and equalizer iterative optimizationscheme based on signal to interference plus noise ratio(SINR)is proposed.The scheme makes the maximization of SINR for the iterative optimization target,under the premise that the initial equalizer and the iteration termination threshold have given,taking the maximum SINR value by alternately updating the precoder and the equalizer,which effectively suppresses user interference and inter-carrier interference,reduces the bit error rate of the system,and ensures the quality of user communication in the frequency selective channel environment.