Universal Filtered Multicarrier Transmisssion Scheme For 5G Mobile Communication System

To adapt to explosive increase of mobile data traffic,massive amounts of device connection and emerging new traffic types and application scenarios,the fifith generation communication(5G)system emerge in response to the needs of times.Internet of things and machine type communication will play an important role in 5G communication system.The new demands in 5G communication system put forward new requirements for 5G physical architecture,especially requirements for resisting against carrier frequency offset(CFO)and symbol timing offset(STO).Considering the limitation of LTE mechanism and CP-OFDM waveform,new air interface especially new multicarrier transmission scheme become key technique of 5G physical architecture design as well as research hot spot of 5G organizations.Our paper mainly focus on Universal-filtered Multicarrier(UFMC)transmission scheme in 5G mobile communication system.The main work are as follows:First of all,we investigate on several 5G candidate multicarrier transmission schemes mostly researched in academic community these days,including Filter Bank Multicarrier(FBMC),General-filtered Multicarrier(GFDM)and Universal-filtered Multicarrier.We have a comparative analysis for them in terms of theory,transceiver architecture,performance and implementation complexity.Finally,we choose UFMC as the research focus of our paper.Secondly,performance research of resisting against CFO and STO are done for UFMC transmission scheme and advantage of UFMC over OFDM against CFO and STO are proved by simulation,qualifying UFMC a suitable candidate transmission plan for 5G.We establish a UFMC system model including CFO and simulation shows that no matter in Guass channel or Rayleigh channel and no matter based on ideal channel equalization or channel estimation equalization,UFMC system outperforms OFDM system and UFMC shows strong robustness against CFO.In addition,we establish a multi-user uplink system containing a quasi-synchronized user to evaluate on anti-symbol timing offset(STO)performance for UFMC.Simulation shows that UFMC have symmetrical property in terms of MSE vs STO and can support open-loop synchronization and autonomous timing advance mechanism in 5G communication system better.In addition,UFMC has stronger robustness for all range of STO and outperforms OFDM in most circumstance with STO,thus is a multicarrier transmission scheme suitable for 5G air interface.In addition,we compose a UFMC-MIMO transceiver architecture and corresponding beamforming scheme.The composed scheme has preferable symbol error rate(SER)performance and can reserve advantage of UFMC over OFDM against CFO.UFMC is a widely acknowledged 5G candidate multicarrier transmission scheme,but how to combine UFMC with MIMO technique has been rarely studied in academic community.Our paper discuss MIMO transceiver architecture based on UFMC transmission scheme.We come up with a feasible scheme including transmitter,receiver and beamforming algorithm.We prove the proposed scheme can recover data correctly by mathematical derivation.Simulaiton shows the composed UFMC-MIMO scheme has preferable SER performance and retains performance advantage of UFMC and outperforms OFDM-MIMO.Finally,we compose channel estimation algorithm based on equal pilot for UFMC.We separately design channel estimation algorithm based on block pilot in slow fading channel and based on comb pilot in fast fading channel and get the same channel estimation performance as OFDM to ensure UFMC applied in 5G scene.Considering UFMC has different transceiver architecture from OFDM,how to design channel estimation scheme and if good performance can be achieved remains a question.First,we design channel estimation algorithm based on block pilot in slow fading channel.We compose equal pilot and equal channel estimation separately and the simulations shows that equal estimation pilot has better performance.Besides,equal pilot estimation combined with frequency domain averaging noise sliding window has the best performance in all algorithms and approximate ideal channel equalization performance.Further,we design channel estimation algorithm based on comb pilot in fast fading channel.We design two pilot pattern.Frequency domain all-pilot time domain interpolation pilot gets better performance but consumes more pilots.Frequency domain and time domain two dimension interpolation pilot consumes less pilots but has little decrease in performance.The decision can be made based on the scene.No matter which pilot pattern achieves the same channel estimation performance as OFDM to ensure UFMC applied in 5G scene.