A correlation overlapping partial transmit sequence(C-OPTS) algorithm is proposed to solve the issue of high complexity of overlapping partial transmit sequence(OPTS) algorithm in suppressing the peak to average power...A correlation overlapping partial transmit sequence(C-OPTS) algorithm is proposed to solve the issue of high complexity of overlapping partial transmit sequence(OPTS) algorithm in suppressing the peak to average power ratio(PAPR) of filter bank multicarrier-offset quadrature amplitude modulation(FBMC-OQAM) signals.The V subblocks in partial transmit sequence(PTS) are regrouped into U combinations according to the correlation coefficient p,and overlapping subblocks are allowed between adjacent groups.The search starts from the first group and sets the phase factors of the subsequent groups to 1.When the phase factors of the non-overlapping subblocks in the first group are determined,the subsequent groups are searched in turn to determine their respective phase factors.Starting from the second data block,the data overlapped with it should be taken into account when determining its optimal phase factor vector.Theoretical analysis and simulation results indicate that compared with the OPTS algorithm,the proposed algorithm can significantly reduce the computational complexity at the cost of slight deterioration of PAPR performance.Meanwhile,compared with the even-odd iterative double-layers OPTS(ID-OPTS) algorithm,it can further reduce the complexity and obtain a better PAPR suppression effect.展开更多
FBMC/OQAM transmission system has a better spectral efficiency than OFDM.However,its orthogonality condition is only considered in the real field.In the presence of fading channels,the real orthogonality of FBMC/OQAM ...FBMC/OQAM transmission system has a better spectral efficiency than OFDM.However,its orthogonality condition is only considered in the real field.In the presence of fading channels,the real orthogonality of FBMC/OQAM might be lost,which calls for new equalization schemes.In this paper,an improved equalizer with real interference prediction(ERIP)scheme of FBMC/OQAM is proposed.We analyze the correlation between the real and the neighboring imaginary interference components taking Doppler shifts into account,and derive the improved ERIP scheme.The simulation results show that the proposed scheme can outperform the original ERIP and the one-tap equalization in time-varying multipath scenarios with an affordable complexity.展开更多
Filter-bank multicarrier （FBMC） with offset quadrature amplitude modulation （OQAM） is a candidate waveform for future wireless communications due to its advantages over orthogonal frequency division multiplexing ...Filter-bank multicarrier （FBMC） with offset quadrature amplitude modulation （OQAM） is a candidate waveform for future wireless communications due to its advantages over orthogonal frequency division multiplexing （OFDM） systems. However, because of or-thogonality in real field and the presence of imaginary intrinsic interference, channel estimation in FBMC is not as straightforward as OFDM systems especially in multiple antenna scenarios. In this paper, we propose a channel estimation method which employs intrinsic interference cancellation at the transmitter side. The simulation results show that this method has less pilot overhead, less peak to average power ratio （PAPR）, better bit error rate （BER）, and better mean square error （MSE） performance compared to the well-known intrinsic approximation methods （IAM）.展开更多
滤波器组多载波(Filter Bank Multi-Carrier,FBMC)与偏移正交振幅调制(Offset Quadrature Amplitude Modulation,OQAM)相结合的FBMC-OQAM技术在无线通信系统中具有频谱效率高和无需同步等特点。然而,FBMC-OQAM系统较高的峰均功率比(Peak...滤波器组多载波(Filter Bank Multi-Carrier,FBMC)与偏移正交振幅调制(Offset Quadrature Amplitude Modulation,OQAM)相结合的FBMC-OQAM技术在无线通信系统中具有频谱效率高和无需同步等特点。然而,FBMC-OQAM系统较高的峰均功率比(Peak-to-Average Power Ratio,PAPR)容易导致信号失真、频谱扩展、系统性能下降。鉴于此,文中提出一种载波预留(Tone Reservation,TR)和μ-律压扩联合的新方法(TR-μLaw)来降低FBMCOQAM系统的PAPR。TR方法具有无失真特性,而μ-律压扩法虽然给FBMC-OQAM系统带来了一定失真,但是能显著降低PAPR。TR-μLaw方法将二者结合,实现了两种方法的利弊互补。仿真结果表明,TR-μLaw方法在降低PAPR方面的性能优于μ-律压扩法和TR方法,在μ=3和Iterations=8时TR-μLaw方法的PAPR较后两者分别降低约1.0dB和3.4dB,且BER性能优于μ-律压扩法。展开更多
针对多径条件下,FBMC/OQAM系统采用分散式导频结构的信道估计算法存在导频功率开销过大的问题,提出一种基于双导频的功率优化信道估计算法(DDP with FFT)。在传统双导频信道估计(DDP)的基础上,主动引入相位模糊,降低传输导频对的功率消...针对多径条件下,FBMC/OQAM系统采用分散式导频结构的信道估计算法存在导频功率开销过大的问题,提出一种基于双导频的功率优化信道估计算法(DDP with FFT)。在传统双导频信道估计(DDP)的基础上,主动引入相位模糊,降低传输导频对的功率消耗,利用多径信道能量集中的特点,对引入的相位模糊进行估计,进一步保证信道估计准确度。理论分析和仿真结果表明,提出的优化算法可以有效降低导频功率开销,实现高精度信道估计性能。展开更多
部分传输序列(Partial Transmit Sequence,PTS)是降低正交频分复用(Orthogonal Frequency Division Multiplexing,OFDM)系统峰均比(Peak-to-Average Power Ratio,PAPR)的有效方法,但是PTS穷举法搜索最优解,使系统复杂度增加。针对这一...部分传输序列(Partial Transmit Sequence,PTS)是降低正交频分复用(Orthogonal Frequency Division Multiplexing,OFDM)系统峰均比(Peak-to-Average Power Ratio,PAPR)的有效方法,但是PTS穷举法搜索最优解,使系统复杂度增加。针对这一缺点进行改进,提出了基于离散粒子群优化的部分传输序列(Partial Transmit Sequence based on Discrete Particle Swarm Optimization,PTS-DPSO)方法,并将其应用到基于偏移正交幅度调制的滤波器组多载波系统(Filter Bank Multicarrier with Offset Quadrature Amplitude Modulation,FBMC/OQAM)中。PTS-DPSO利用离散粒子群优化搜寻最优解,避免了系统复杂度的增加。通过仿真验证,PTS-DPSO可以有效抑制FBMC/OQAM系统过高的PAPR且误码率低。展开更多
色散选择性映射(dispersive selected mapping,DSLM)是降低基于偏移正交幅度调制的滤波器组多载波(filter bank multicarrier with offset quadrature amplitude modulation,FBMC/OQAM)系统峰均比(peak to average power ratio,PAPR)的...色散选择性映射(dispersive selected mapping,DSLM)是降低基于偏移正交幅度调制的滤波器组多载波(filter bank multicarrier with offset quadrature amplitude modulation,FBMC/OQAM)系统峰均比(peak to average power ratio,PAPR)的技术,但是该方法需要传输额外比特边带信息(side information,SI)。为了抑制FBMC/OQAM系统的PAPR,提高系统的频谱利用率,在DSLM的基础上,提出了一种无边带信息的色散选择性映射(without side information of DSLM,W-DSLM)方法。W-DSLM通过在相位序列中挑选特定的位置,并插入模值大于1的扩展因子对相位序列进行改进,然后利用扩展因子与相邻位置的能量差,在接收端得到最优相位序列,从而恢复出传输的符号。扩展因子的插入避免了边带信息的传输,因此能够有效提高系统的频谱效率。仿真结果验证了该方法的有效性。展开更多
水声信道是一个时变的双扩散信道,不仅会引起传输信号的时频扩展,而且会造成严重的信息损失。由于滤波器组多载波/交错正交幅度调制(Filter Bank Based Multicarrier/Offset Quadrature Amplitude Modulation, FBMC/OQAM)系统可通过改...水声信道是一个时变的双扩散信道,不仅会引起传输信号的时频扩展,而且会造成严重的信息损失。由于滤波器组多载波/交错正交幅度调制(Filter Bank Based Multicarrier/Offset Quadrature Amplitude Modulation, FBMC/OQAM)系统可通过改变发送信号的成型脉冲来减小时频扩展带来的符号干扰和子载波干扰,因此更适合快速时变的水下声信道。为了降低现有成型脉冲设计算法的优化难度,提出了一种快速且易于实现的成型脉冲设计方法,该方法根据信道时频统计特性对扩展高斯函数(Extend Gaussian Function, EGF)进行了优化,实现了期望信号能量最大化,并在时域符号间加入适当的保护间隔,进一步增强了抗多途干扰的能力。仿真结果表明,无论在高频散信道还是在低频信道下,相比于其它成型脉冲算法,该算法在降低计算量的同时,改进了的FBMC/OQAM系统的传输性能,误码率降低了2～3 dB。展开更多
针对具有偏移正交幅度调制的滤波器组多载波(Filter Bank Multicarrier with Offset Quadrature Amplitude Modulation,FBMC-OQAM)系统中目前存在的定时同步算法问题,提出了一种改进的定时同步算法。该算法利用两个特殊设计的符号,将其...针对具有偏移正交幅度调制的滤波器组多载波(Filter Bank Multicarrier with Offset Quadrature Amplitude Modulation,FBMC-OQAM)系统中目前存在的定时同步算法问题,提出了一种改进的定时同步算法。该算法利用两个特殊设计的符号,将其连续通过FBMC-OQAM系统后在时域形成共轭对称特性的信号。与现有的算法相比,该算法增加了计算相关序列的长度,但减少了训练符号,还去除了高旁瓣带来的干扰。理论分析与仿真结果表明,改进算法具有更好的定时同步性能。展开更多
基金Supported by the National Natural Science Foundation of China(No.61601296,61701295,61801286)the Major Scientific and Technological Innovation Projects in Chengdu(No.2019-YF08-00082-GX)the Talent Program of Shanghai University of Engineering Science(No.2018RC43)。
文摘A correlation overlapping partial transmit sequence(C-OPTS) algorithm is proposed to solve the issue of high complexity of overlapping partial transmit sequence(OPTS) algorithm in suppressing the peak to average power ratio(PAPR) of filter bank multicarrier-offset quadrature amplitude modulation(FBMC-OQAM) signals.The V subblocks in partial transmit sequence(PTS) are regrouped into U combinations according to the correlation coefficient p,and overlapping subblocks are allowed between adjacent groups.The search starts from the first group and sets the phase factors of the subsequent groups to 1.When the phase factors of the non-overlapping subblocks in the first group are determined,the subsequent groups are searched in turn to determine their respective phase factors.Starting from the second data block,the data overlapped with it should be taken into account when determining its optimal phase factor vector.Theoretical analysis and simulation results indicate that compared with the OPTS algorithm,the proposed algorithm can significantly reduce the computational complexity at the cost of slight deterioration of PAPR performance.Meanwhile,compared with the even-odd iterative double-layers OPTS(ID-OPTS) algorithm,it can further reduce the complexity and obtain a better PAPR suppression effect.
基金This paper is supported in part by NSFC China(61771309,61671301)Shanghai Commission of Science and Technology Funding(SCST 15DZ2270400)+1 种基金Shanghai Key Laboratory Funding(STCSM 18DZ1200102)Medical Engineering Cross Research Foundation of Shanghai Jiao Tong University(YG2017QN47).
文摘FBMC/OQAM transmission system has a better spectral efficiency than OFDM.However,its orthogonality condition is only considered in the real field.In the presence of fading channels,the real orthogonality of FBMC/OQAM might be lost,which calls for new equalization schemes.In this paper,an improved equalizer with real interference prediction(ERIP)scheme of FBMC/OQAM is proposed.We analyze the correlation between the real and the neighboring imaginary interference components taking Doppler shifts into account,and derive the improved ERIP scheme.The simulation results show that the proposed scheme can outperform the original ERIP and the one-tap equalization in time-varying multipath scenarios with an affordable complexity.
基金supported by ZTE Industry-Academia-Research Cooperation Funds under Grant No.Surrey-Ref-9953
文摘Filter-bank multicarrier （FBMC） with offset quadrature amplitude modulation （OQAM） is a candidate waveform for future wireless communications due to its advantages over orthogonal frequency division multiplexing （OFDM） systems. However, because of or-thogonality in real field and the presence of imaginary intrinsic interference, channel estimation in FBMC is not as straightforward as OFDM systems especially in multiple antenna scenarios. In this paper, we propose a channel estimation method which employs intrinsic interference cancellation at the transmitter side. The simulation results show that this method has less pilot overhead, less peak to average power ratio （PAPR）, better bit error rate （BER）, and better mean square error （MSE） performance compared to the well-known intrinsic approximation methods （IAM）.
文摘滤波器组多载波(Filter Bank Multi-Carrier,FBMC)与偏移正交振幅调制(Offset Quadrature Amplitude Modulation,OQAM)相结合的FBMC-OQAM技术在无线通信系统中具有频谱效率高和无需同步等特点。然而,FBMC-OQAM系统较高的峰均功率比(Peak-to-Average Power Ratio,PAPR)容易导致信号失真、频谱扩展、系统性能下降。鉴于此,文中提出一种载波预留(Tone Reservation,TR)和μ-律压扩联合的新方法(TR-μLaw)来降低FBMCOQAM系统的PAPR。TR方法具有无失真特性,而μ-律压扩法虽然给FBMC-OQAM系统带来了一定失真,但是能显著降低PAPR。TR-μLaw方法将二者结合,实现了两种方法的利弊互补。仿真结果表明,TR-μLaw方法在降低PAPR方面的性能优于μ-律压扩法和TR方法,在μ=3和Iterations=8时TR-μLaw方法的PAPR较后两者分别降低约1.0dB和3.4dB,且BER性能优于μ-律压扩法。
文摘针对多径条件下,FBMC/OQAM系统采用分散式导频结构的信道估计算法存在导频功率开销过大的问题,提出一种基于双导频的功率优化信道估计算法(DDP with FFT)。在传统双导频信道估计(DDP)的基础上,主动引入相位模糊,降低传输导频对的功率消耗,利用多径信道能量集中的特点,对引入的相位模糊进行估计,进一步保证信道估计准确度。理论分析和仿真结果表明,提出的优化算法可以有效降低导频功率开销,实现高精度信道估计性能。
文摘部分传输序列(Partial Transmit Sequence,PTS)是降低正交频分复用(Orthogonal Frequency Division Multiplexing,OFDM)系统峰均比(Peak-to-Average Power Ratio,PAPR)的有效方法,但是PTS穷举法搜索最优解,使系统复杂度增加。针对这一缺点进行改进,提出了基于离散粒子群优化的部分传输序列(Partial Transmit Sequence based on Discrete Particle Swarm Optimization,PTS-DPSO)方法,并将其应用到基于偏移正交幅度调制的滤波器组多载波系统(Filter Bank Multicarrier with Offset Quadrature Amplitude Modulation,FBMC/OQAM)中。PTS-DPSO利用离散粒子群优化搜寻最优解,避免了系统复杂度的增加。通过仿真验证,PTS-DPSO可以有效抑制FBMC/OQAM系统过高的PAPR且误码率低。
文摘色散选择性映射(dispersive selected mapping,DSLM)是降低基于偏移正交幅度调制的滤波器组多载波(filter bank multicarrier with offset quadrature amplitude modulation,FBMC/OQAM)系统峰均比(peak to average power ratio,PAPR)的技术,但是该方法需要传输额外比特边带信息(side information,SI)。为了抑制FBMC/OQAM系统的PAPR,提高系统的频谱利用率,在DSLM的基础上,提出了一种无边带信息的色散选择性映射(without side information of DSLM,W-DSLM)方法。W-DSLM通过在相位序列中挑选特定的位置,并插入模值大于1的扩展因子对相位序列进行改进,然后利用扩展因子与相邻位置的能量差,在接收端得到最优相位序列,从而恢复出传输的符号。扩展因子的插入避免了边带信息的传输,因此能够有效提高系统的频谱效率。仿真结果验证了该方法的有效性。
文摘针对具有偏移正交幅度调制的滤波器组多载波(Filter Bank Multicarrier with Offset Quadrature Amplitude Modulation,FBMC-OQAM)系统中目前存在的定时同步算法问题,提出了一种改进的定时同步算法。该算法利用两个特殊设计的符号,将其连续通过FBMC-OQAM系统后在时域形成共轭对称特性的信号。与现有的算法相比,该算法增加了计算相关序列的长度,但减少了训练符号,还去除了高旁瓣带来的干扰。理论分析与仿真结果表明,改进算法具有更好的定时同步性能。
