Orthogonal Frequency Division Multiplexing(OFDM) is an effective technique to deal with a frequency selective channel since it can convert the channel into some flat fading subchannels.However,very different output SN...Orthogonal Frequency Division Multiplexing(OFDM) is an effective technique to deal with a frequency selective channel since it can convert the channel into some flat fading subchannels.However,very different output SNR values of the subchannels will lead to poor bit error performance when a linear equalizer and Equal Bit Allocation(EBA) are adopted in OFDM systems.So,we proposed three novel nonlinear Joint Transceiver(JT) schemes based on Zero-Forcing(ZF) criterion and Minimum Mean Square Error(MMSE) criterion respectively,which can transform all subchannels of an OFDM system into subchannels with identical channel gain.Thus,EBA is equivalent to the Optimum Bit Allocation(OBA) for these subchannels.Numerical analysis helps us to obtain the theoretical approximate BER values of the JT scheme.Simulation results verify the numerical analysis and confirm that the performance of our proposed JT scheme greatly outperforms the traditional linear equalizer with EBA at moderate and high SNR values.展开更多
基金the National Natural Science Foundation of China for Distinguished Young Scholars，the National Key Basic Research Program of China (973 program)，the National Natural Science Foundation of China，the National Science and Technology Major Project，the Special Research Fund of State Key Laboratory，the 111 Project
文摘Orthogonal Frequency Division Multiplexing(OFDM) is an effective technique to deal with a frequency selective channel since it can convert the channel into some flat fading subchannels.However,very different output SNR values of the subchannels will lead to poor bit error performance when a linear equalizer and Equal Bit Allocation(EBA) are adopted in OFDM systems.So,we proposed three novel nonlinear Joint Transceiver(JT) schemes based on Zero-Forcing(ZF) criterion and Minimum Mean Square Error(MMSE) criterion respectively,which can transform all subchannels of an OFDM system into subchannels with identical channel gain.Thus,EBA is equivalent to the Optimum Bit Allocation(OBA) for these subchannels.Numerical analysis helps us to obtain the theoretical approximate BER values of the JT scheme.Simulation results verify the numerical analysis and confirm that the performance of our proposed JT scheme greatly outperforms the traditional linear equalizer with EBA at moderate and high SNR values.
