Research On Filter Bank Multicarrier In 5G Uplink

The rapid development of 5G communication and the diversification of scenarios have proposed higher requirements for uplink transmission:interconnections whenever and wherever possible among more devices,faster data transmission rate,higher system capacity,lower power consumption of terminals and shorter transmission delays.Orthogonal Frequency Division Multiplexing(OFDM)is limited by its strict synchronous condition,high secondary lobes,and low spectrum resource utilization and so on.Filter Bank Multicarrier(FBMC)is one of the key technologies in 5G physical layer.As a non-orthogonal waveform,FBMC has many advantages such as higher spectrum efficiency,lower secondary lobes and better time frequency localization(TFL).At present,which waveform will be applied to 5G communication is not confirmed yet,and criteria to judge 5G new waveforms also are diversity.FBMC on 5G uplink transmission is still in the stage of theoretical research,and its performances under this scenario is in lack of link level simulation validation.Due to time-frequency asynchronous problem that exist in multi-user transmission,FBMC' robustness of synchronization error is lack of fully validation.When FBMC is applied on uplink transmission,there are many schemes to suppress its Peak Power Ratio(Peak to Average Power Ratio,PAPR),but the effectiveness and complexity of these schemes are under evaluation.In view of the above situation,MATLAB simulation platform has been set up to evaluate FBMC's performance in many aspects,and the main contributions of this paper are as follows:(1)Firstly we analyze FBMC's transceiver principle,and deduce the of prototype filter who is based on Nyquist theory.Then we study how prototype filter with various roll-off factors effects on time-frequency localization.At last,we obtain the advantages of PHYDYAS filter.By the canalization of power spectrum density,the application of filter bank can reduce FBMC's out-of-band power effectively.(2)Because high computational complexity leads to higher hardware requirements and longer time delay,communication system expects lower complexity.After making theoretical derivation and simulation validation of FBMC and OFDM,we research on how overlap factor and the Fourier transform points affect FBMC computational complexity.(3)Based on the theoretical derivation of spectrum efficiency and time efficiency,the performance differences between FBMC and OFDM are analyzed,and then their applicability with different length packets is further studied.Under synchronous transmission scenarios,block error rate and throughput with different modulation schemes when applying FBMC or OFDM are researched.(4)The 5G uplink multi-user asynchronous scenario is firstly modeled,and the influence of time or frequency errors on communication system are further studied,and then FBMC's robustness on synchronism deviation are analyzed by quantitation.After research on the influence of guard band,we study if the prototype filter who has better time-frequency localization can contribute to smaller overhead of guard subcarriers and higher spectrum utilization.(5)Using the existing two kinds of PAPR suppression schemes-Discrete Fourier Transform(DFT)spreading method and Filter Bank(FB)spreading method to reduce PAPR,their principles,performance differences and complexity are researched afterwards.