Research On Technologies In Imperfect Reconstruction-based Filter Bank Multi-carrier

In this thesis,the author proposes a zero padding(ZP)based imperfect reconstruction filter bank multi-carrier(FBMC)system in the uplink of multi-user networks,known as ZP-FBMA.The prototype filter in this system is a common low-pass filter without perfect reconstruction or nearly perfect reconstruction constraint.ZP processing is performed on the input signal at the transmitter side and the received signal is processed by overlap and addition at the receiver side.A variety of receivers are proposed in this thesis,including time domain equalization receiver,down sampling frequency domain equalization receiver and analysis filter bank(AFB)frequency domain equalization receiver.Joint frequency domain equalization is also proposed to eliminate the inter sub-band interference.The theoretical analysis and simulation results illustrate that the proposed ZP-FBMA system has lower peak to average power ratio,better bit error rate(BER)performance,better robustness to carrier frequency offset and less data rate loss than cyclic prefix-based orthogonal frequency division multiple access system,single carrier frequency division multiple access system and perfect reconstruction filter bank multiple access system(PR-FBMA).ZP-FBMA is essentially a non-orthogonal multiple access system.Inter user interference always exists and increases the difficulty of channel equalization,resulting in the deterioration of system performance.Owing to the problem that BER performance of ZP-FBMA system has not been greatly improved in some scenarios,the author further proposes optimal design of the receiver.The estimated signal of initial detection is fed back to the interference cancellation unit in order to eliminate interferences between users and single user detection is applied after interference cancellation.A variety of single user receivers are proposed in this thesis,including single user time domain equalization receiver,single user down sampling frequency domain equalization receiver,single user AFB frequency domain equalization receiver and single user vertical bell laboratories layered space-time receiver,which further enhance BER performance of the system.In addition,the author proposes optimal design of filters based on communication indicator optimization in order to improve the transmission performance of single user in multipath channel on the basis of interference cancellation.The optimization includes the selection of multiphase components and the cut-off frequency optimization of the prototype.The multiphase component selection makes full use of the remaining multiphase components that are discarded in the PR-FBMC system.The cut-off frequency optimization obtains the optimal BER performance based on some criteria by adjusting the cut-off frequency of the prototype filter.Simulation results show that BER performance of the system can be further improved.Therefore,the proposed ZP-FBMA communication system will have a good application prospect in the foreseeable future.