In this paper,we formulate the precoding problem of integrated sensing and communication(ISAC)waveform as a non-convex quadratically constrained quadratic programming(QCQP),in which the weighted sum of communication m...In this paper,we formulate the precoding problem of integrated sensing and communication(ISAC)waveform as a non-convex quadratically constrained quadratic programming(QCQP),in which the weighted sum of communication multi-user interference(MUI)and the gap between dual-use waveform and ideal radar waveform is minimized with peak-toaverage power ratio(PAPR)constraints.We propose an efficient algorithm based on alternating direction method of multipliers(ADMM),which is able to decouple multiple variables and provide a closed-form solution for each subproblem.In addition,to improve the sensing performance in both spatial and temporal domains,we propose a new criteria to design the ideal radar waveform,in which the beam pattern is made similar to the ideal one and the integrated sidelobe level of the ambiguity function in each target direction is minimized in the region of interest.The limited memory Broyden-Fletcher-Goldfarb-Shanno(LBFGS)algorithm is applied to the design of the ideal radar waveform which works as a reference in the design of the dual-function waveform.Numerical results indicate that the designed dual-function waveform is capable of offering good communication quality of service(QoS)and sensing performance.展开更多
针对传统部分传输序列(Partial Transmit Sequence,PTS)算法在改善正交频分复用(Orthogonal Frequency Division Multiplexing,OFDM)系统峰均功率比(Peak to Average Power Ratio,PAPR)时存在较高计算复杂度问题,文章提出了一种改进PTS...针对传统部分传输序列(Partial Transmit Sequence,PTS)算法在改善正交频分复用(Orthogonal Frequency Division Multiplexing,OFDM)系统峰均功率比(Peak to Average Power Ratio,PAPR)时存在较高计算复杂度问题,文章提出了一种改进PTS算法。该算法利用分治思想对候选相位因子序列进行分组,降低其序列维度;结合相位加权序列的特点,进一步降低需遍历的候选序列个数,从而降低了计算复杂度。与传统的PTS算法对比,所提出的改进算法在改善PAPR性能的同时,较大地降低了计算复杂度。展开更多
Orthogonal time frequency space(OTFS)modulation has been proven to be superior to traditional orthogonal frequency division multiplexing(OFDM)systems in high-speed communication scenarios.However,the existing channel ...Orthogonal time frequency space(OTFS)modulation has been proven to be superior to traditional orthogonal frequency division multiplexing(OFDM)systems in high-speed communication scenarios.However,the existing channel estimation schemes may results in poor peak to average power ratio(PAPR)performance of OTFS system or low spectrum efficiency.Hence,in this paper,we propose a low PAPR channel estimation scheme with high spectrum efficiency.Specifically,we design a multiple scattered pilot pattern,where multiple low power pilot symbols are superimposed with data symbols in delay-Doppler domain.Furthermore,we propose the placement rules for pilot symbols,which can guarantee the low PAPR.Moreover,the data aided iterative channel estimation was invoked,where joint channel estimation is proposed by exploiting multiple independent received signals instead of only one received signal in the existing scheme,which can mitigate the interference imposed by data symbols for channel estimation.Simulation results shows that the proposed multiple scattered pilot aided channel estimation scheme can significantly reduce the PAPR while keeping the high spectrum efficiency.展开更多
针对滤波器组多载波-偏移正交幅度调制技术(Filter Bank Multicarrier-Offset Quadrature Amplitude Modulation,FBMC-OQAM)存在峰均功率比(Peak-to-Average Power Ratio,PAPR)过高的问题,以及传统部分传输序列(Partial Transfer Sequen...针对滤波器组多载波-偏移正交幅度调制技术(Filter Bank Multicarrier-Offset Quadrature Amplitude Modulation,FBMC-OQAM)存在峰均功率比(Peak-to-Average Power Ratio,PAPR)过高的问题,以及传统部分传输序列(Partial Transfer Sequence,PTS)算法对PAPR抑制效果不明显,提出了一种新的基于自适应搜索策略的人工蜂群部分传输序列算法(Adaptive Search Strategy Based Artifical Bee Colony PTS,ASSABC-PTS)。首先,根据FBMC-OQAM系统特性,利用传统PTS算法对系统进行初步优化,以降低FBMC-OQAM系统的PAPR;然后,针对PTS算法中存在的计算复杂度问题,引入人工蜂群(Artificial Bee Colony,ABC)算法进行优化;最后,在ABC算法中引入自适应搜索策略提升算法的局部寻优能力,加快ABC算法的收敛速度和搜索精度。仿真实验表明,ASSABC-PTS在有效降低系统算法复杂度的同时,也极大降低了FBMC-OQAM系统的峰均功率比。展开更多
The internet of things(IoT)has been widely considered to be integrated with high-speed railways to improve safety and service.It is important to achieve reliable communication in IoT for railways(IoT-R)under high mobi...The internet of things(IoT)has been widely considered to be integrated with high-speed railways to improve safety and service.It is important to achieve reliable communication in IoT for railways(IoT-R)under high mobility scenarios and strict energy constraints.Orthogonal time frequency space(OTFS)modulation is a two-dimensional modulation technique that has the potential to overcome the challenges in high Doppler environments.In addition,OTFS can have lower peak-to-average power ratio(PAPR)compared to orthogonal frequency division multiplexing,which is especially important for the application of IoT-R.Therefore,OTFS modulation for IoT-R is investigated in this paper.In order to decrease PAPR of OTFS and promote the application of OTFS modulation in IoT-R,the peak windowing technique is used in this paper.This technique can reduce the PAPR of OTFS by reducing the peak power and does not require multiple iterations.The impacts of different window functions,window sizes and clipping levels on PAPR and bit error rate of OTFS are simulated and discussed.The simulation results show that the peak windowing technique can efficiently reduce the PAPR of OTFS for IoT-R.展开更多
根据世界卫生组GLOBOCAN数据库2020年全球癌症统计数据,在全世界范围内,前列腺癌发病率位于男性恶性肿瘤第二位^([1])。近年来,前列腺癌已成为我国男性泌尿生殖系统最常见的恶性肿瘤,位居男性恶性肿瘤的第六位^([2-3])。2023年9月,美国...根据世界卫生组GLOBOCAN数据库2020年全球癌症统计数据,在全世界范围内,前列腺癌发病率位于男性恶性肿瘤第二位^([1])。近年来,前列腺癌已成为我国男性泌尿生殖系统最常见的恶性肿瘤,位居男性恶性肿瘤的第六位^([2-3])。2023年9月,美国国立综合癌症网(National Comprehensive Cancer Network,NCCN)制订的2023年V4版《NCCN前列腺癌临床实践指南》(以下简称为指南)进行了更新.展开更多
通过在选择性映射算法(SLM)中引入交叉熵(CE),可以得到最优的符号序列,使SLM算法降低OFDM(Orthogonal Frequency Division Multiplexing)系统峰均功率比的效果达到最优。在CE-SLM(Cross Entropy-Selected mapping)算法实现的过程中,需...通过在选择性映射算法(SLM)中引入交叉熵(CE),可以得到最优的符号序列,使SLM算法降低OFDM(Orthogonal Frequency Division Multiplexing)系统峰均功率比的效果达到最优。在CE-SLM(Cross Entropy-Selected mapping)算法实现的过程中,需经过多次迭代运算,势必增加了算法的复杂度。拟在CE-SLM算法中引入一个快速收敛因子,使得系统中的采样概率快速收敛到0或者1的状态,降低了优化符号序列所需的迭代次数。仿真结果表明:改进算法在保持与CE-SLM算法降低PAPR(Peak-to-Average Power Ratio)效果一致的情况下,降低了得到最优符号序列所需的迭代次数,使得算法的复杂度得到有效降低。展开更多
基金supported in part by the National Natural Science Foundation of China under Grant 62271142in part by the Key Research and Development Program of Jiangsu Province BE2023021+2 种基金in part by the Jiangsu Key Research and Development Program Project under Grant BE2023011-2in part by the Young Scholar Funding of Southeast Universityin part by the Fundamental Research Funds for the Central Universities 2242022k60001。
文摘In this paper,we formulate the precoding problem of integrated sensing and communication(ISAC)waveform as a non-convex quadratically constrained quadratic programming(QCQP),in which the weighted sum of communication multi-user interference(MUI)and the gap between dual-use waveform and ideal radar waveform is minimized with peak-toaverage power ratio(PAPR)constraints.We propose an efficient algorithm based on alternating direction method of multipliers(ADMM),which is able to decouple multiple variables and provide a closed-form solution for each subproblem.In addition,to improve the sensing performance in both spatial and temporal domains,we propose a new criteria to design the ideal radar waveform,in which the beam pattern is made similar to the ideal one and the integrated sidelobe level of the ambiguity function in each target direction is minimized in the region of interest.The limited memory Broyden-Fletcher-Goldfarb-Shanno(LBFGS)algorithm is applied to the design of the ideal radar waveform which works as a reference in the design of the dual-function waveform.Numerical results indicate that the designed dual-function waveform is capable of offering good communication quality of service(QoS)and sensing performance.
文摘针对传统部分传输序列(Partial Transmit Sequence,PTS)算法在改善正交频分复用(Orthogonal Frequency Division Multiplexing,OFDM)系统峰均功率比(Peak to Average Power Ratio,PAPR)时存在较高计算复杂度问题,文章提出了一种改进PTS算法。该算法利用分治思想对候选相位因子序列进行分组,降低其序列维度;结合相位加权序列的特点,进一步降低需遍历的候选序列个数,从而降低了计算复杂度。与传统的PTS算法对比,所提出的改进算法在改善PAPR性能的同时,较大地降低了计算复杂度。
基金supported by National Natural Science Foundation of China(No.61871452)。
文摘Orthogonal time frequency space(OTFS)modulation has been proven to be superior to traditional orthogonal frequency division multiplexing(OFDM)systems in high-speed communication scenarios.However,the existing channel estimation schemes may results in poor peak to average power ratio(PAPR)performance of OTFS system or low spectrum efficiency.Hence,in this paper,we propose a low PAPR channel estimation scheme with high spectrum efficiency.Specifically,we design a multiple scattered pilot pattern,where multiple low power pilot symbols are superimposed with data symbols in delay-Doppler domain.Furthermore,we propose the placement rules for pilot symbols,which can guarantee the low PAPR.Moreover,the data aided iterative channel estimation was invoked,where joint channel estimation is proposed by exploiting multiple independent received signals instead of only one received signal in the existing scheme,which can mitigate the interference imposed by data symbols for channel estimation.Simulation results shows that the proposed multiple scattered pilot aided channel estimation scheme can significantly reduce the PAPR while keeping the high spectrum efficiency.
文摘针对滤波器组多载波-偏移正交幅度调制技术(Filter Bank Multicarrier-Offset Quadrature Amplitude Modulation,FBMC-OQAM)存在峰均功率比(Peak-to-Average Power Ratio,PAPR)过高的问题,以及传统部分传输序列(Partial Transfer Sequence,PTS)算法对PAPR抑制效果不明显,提出了一种新的基于自适应搜索策略的人工蜂群部分传输序列算法(Adaptive Search Strategy Based Artifical Bee Colony PTS,ASSABC-PTS)。首先,根据FBMC-OQAM系统特性,利用传统PTS算法对系统进行初步优化,以降低FBMC-OQAM系统的PAPR;然后,针对PTS算法中存在的计算复杂度问题,引入人工蜂群(Artificial Bee Colony,ABC)算法进行优化;最后,在ABC算法中引入自适应搜索策略提升算法的局部寻优能力,加快ABC算法的收敛速度和搜索精度。仿真实验表明,ASSABC-PTS在有效降低系统算法复杂度的同时,也极大降低了FBMC-OQAM系统的峰均功率比。
基金supported by the National Key R&D Program of China under Grant 2022YFF0608103the National Natural Science Foundation of China under Grant 62001519 and 62271037。
文摘The internet of things(IoT)has been widely considered to be integrated with high-speed railways to improve safety and service.It is important to achieve reliable communication in IoT for railways(IoT-R)under high mobility scenarios and strict energy constraints.Orthogonal time frequency space(OTFS)modulation is a two-dimensional modulation technique that has the potential to overcome the challenges in high Doppler environments.In addition,OTFS can have lower peak-to-average power ratio(PAPR)compared to orthogonal frequency division multiplexing,which is especially important for the application of IoT-R.Therefore,OTFS modulation for IoT-R is investigated in this paper.In order to decrease PAPR of OTFS and promote the application of OTFS modulation in IoT-R,the peak windowing technique is used in this paper.This technique can reduce the PAPR of OTFS by reducing the peak power and does not require multiple iterations.The impacts of different window functions,window sizes and clipping levels on PAPR and bit error rate of OTFS are simulated and discussed.The simulation results show that the peak windowing technique can efficiently reduce the PAPR of OTFS for IoT-R.
文摘根据世界卫生组GLOBOCAN数据库2020年全球癌症统计数据,在全世界范围内,前列腺癌发病率位于男性恶性肿瘤第二位^([1])。近年来,前列腺癌已成为我国男性泌尿生殖系统最常见的恶性肿瘤,位居男性恶性肿瘤的第六位^([2-3])。2023年9月,美国国立综合癌症网(National Comprehensive Cancer Network,NCCN)制订的2023年V4版《NCCN前列腺癌临床实践指南》(以下简称为指南)进行了更新.
文摘通过在选择性映射算法(SLM)中引入交叉熵(CE),可以得到最优的符号序列,使SLM算法降低OFDM(Orthogonal Frequency Division Multiplexing)系统峰均功率比的效果达到最优。在CE-SLM(Cross Entropy-Selected mapping)算法实现的过程中,需经过多次迭代运算,势必增加了算法的复杂度。拟在CE-SLM算法中引入一个快速收敛因子,使得系统中的采样概率快速收敛到0或者1的状态,降低了优化符号序列所需的迭代次数。仿真结果表明:改进算法在保持与CE-SLM算法降低PAPR(Peak-to-Average Power Ratio)效果一致的情况下,降低了得到最优符号序列所需的迭代次数,使得算法的复杂度得到有效降低。
