This work focuses on maximizing the minimum user’s security energy efficiency(SEE)in an unmanned aerial vehicle-mounted reconfigurable intelligent surface(UAV-RIS)enhanced short-packet communication(SPC)system.The ba...This work focuses on maximizing the minimum user’s security energy efficiency(SEE)in an unmanned aerial vehicle-mounted reconfigurable intelligent surface(UAV-RIS)enhanced short-packet communication(SPC)system.The base station(BS)provides short packet services to ground users using the non-orthogonal multiple access(NOMA)protocol through UAV-RIS,while preventing eavesdropper attacks.To optimize SEE,a joint optimization is performed concerning power allocation,UAV position,decoding order,and RIS phase shifts.An iterative algorithm based on block coordinate descent is proposed for mixed-integer non-convex SEE optimization problem.The original problem is decomposed into three sub-problems,solved alternately using successive convex approximation(SCA),quadratic transformation,penalty function,and semi-definite programming(SDP).Simulation results demonstrate the performance of the UAV-RIS-enhanced short-packet system under different parameters and verify the algorithm’s convergence.Compared to benchmark schemes such as orthogonal multiple access,long packet communication,and sum SEE,the proposed UAV-RIS-enhanced short-packet scheme achieves the higher minimum user’s SEE.展开更多
Ultra-reliable and low-latency communication(URLLC)is still in the early stage of research due to its two strict and conflicting requirements,i.e.,ultra-low latency and ultra-high reliability,and its impact on securit...Ultra-reliable and low-latency communication(URLLC)is still in the early stage of research due to its two strict and conflicting requirements,i.e.,ultra-low latency and ultra-high reliability,and its impact on security performance is still unclear.Specifically,short-packet communication is expected to meet the delay requirement of URLLC,while the degradation of reliability caused by it makes traditional physical-layer security metrics not applicable.In this paper,we investigate the secure short-packet transmission in uplink massive multiuser multiple-inputmultiple-output(MU-MIMO)system under imperfect channel state information(CSI).We propose an artificial noise scheme to improve the security performance of the system and use the system average secrecy throughput(AST)as the analysis metric.We derive the approximate closed-form expression of the system AST and further analyze the system asymptotic performance in two regimes.Furthermore,a one-dimensional search method is used to optimize the maximum system AST for a given pilot length.Numerical results verify the correctness of theoretical analysis,and show that there are some parameters that affect the tradeoff between security and latency.Moreover,appropriately increasing the number of antennas at the base station(BS)and transmission power at user devices(UDs)can increase the system AST to achieve the required threshold.展开更多
Cognitive Internet of Things(IoT)has at-tracted much attention due to its high spectrum uti-lization.However,potential security of the short-packet communications in cognitive IoT becomes an important issue.This paper...Cognitive Internet of Things(IoT)has at-tracted much attention due to its high spectrum uti-lization.However,potential security of the short-packet communications in cognitive IoT becomes an important issue.This paper proposes a relay-assisted maximum ratio combining/zero forcing beamforming(MRC/ZFB)scheme to guarantee the secrecy perfor-mance of dual-hop short-packet communications in cognitive IoT.This paper analyzes the average secrecy throughput of the system and further investigates two asymptotic scenarios with the high signal-to-noise ra-tio(SNR)regime and the infinite blocklength.In ad-dition,the Fibonacci-based alternating optimization method is adopted to jointly optimize the spectrum sensing blocklength and transmission blocklength to maximize the average secrecy throughput.The nu-merical results verify the impact of the system pa-rameters on the tradeoff between the spectrum sensing blocklength and transmission blocklength under a se-crecy constraint.It is shown that the proposed scheme achieves better secrecy performance than other bench-mark schemes.展开更多
极端天气事件的发生会导致电力负荷产生突增或突降,对电网的稳定性和供电能力带来挑战。然而,现有的超短期负荷预测方法对极端天气下非线性和动态变化的负荷特征预测能力有限。为应对极端天气下负荷突变性强及波动剧烈导致的预测精度降...极端天气事件的发生会导致电力负荷产生突增或突降,对电网的稳定性和供电能力带来挑战。然而,现有的超短期负荷预测方法对极端天气下非线性和动态变化的负荷特征预测能力有限。为应对极端天气下负荷突变性强及波动剧烈导致的预测精度降低的问题,提出了一种考虑极端天气的二次重构分解去噪和双向长短时记忆网络(bidirectional long short-term memory,BiLSTM)的超短期电力负荷预测方法。首先,利用最大信息系数选取出能够最大程度反映对负荷影响的气候特征。然后,通过二次重构分解去噪方法提取到负荷多个频段的特征,降低数据复杂性,为BiLSTM模型提供更干净和信息量更清晰的输入序列,从而改善模型的训练效果和预测能力。最后基于比利时、福建省某区域以及得土安市的历史数据集进行算例分析,不同算例中平均绝对百分比误差分别下降到1.024%、0.875%、1.270%和1.009%,实验结果验证了所提方法在极端天气发生时的电力负荷超短期预测方面具有较好的预测性能和广阔的应用前景。展开更多
基金co-supported by the National Natural Science Foundation of China(Nos.U23A20279,62271094)the National Key R&D Program of China(No.SQ2023YFB2500024)+2 种基金the Science Foundation for Youths of Natural Science Foundation of Sichuan Provincial,China(No.2022NSFSC0936)the China Postdoctoral Science Foundation(No.2022M720666)the Open Fund of Key Laboratory of Big Data Intelligent Computing,Chongqing University of Posts and Telecommunications,China(No.BDIC-2023-B-002).
文摘This work focuses on maximizing the minimum user’s security energy efficiency(SEE)in an unmanned aerial vehicle-mounted reconfigurable intelligent surface(UAV-RIS)enhanced short-packet communication(SPC)system.The base station(BS)provides short packet services to ground users using the non-orthogonal multiple access(NOMA)protocol through UAV-RIS,while preventing eavesdropper attacks.To optimize SEE,a joint optimization is performed concerning power allocation,UAV position,decoding order,and RIS phase shifts.An iterative algorithm based on block coordinate descent is proposed for mixed-integer non-convex SEE optimization problem.The original problem is decomposed into three sub-problems,solved alternately using successive convex approximation(SCA),quadratic transformation,penalty function,and semi-definite programming(SDP).Simulation results demonstrate the performance of the UAV-RIS-enhanced short-packet system under different parameters and verify the algorithm’s convergence.Compared to benchmark schemes such as orthogonal multiple access,long packet communication,and sum SEE,the proposed UAV-RIS-enhanced short-packet scheme achieves the higher minimum user’s SEE.
基金supported by the National Key R&D Program of China under Grant 2018YFB1801103the National Natural Science Foundation of China under Grant(no.62171464,no.62122094)。
文摘Ultra-reliable and low-latency communication(URLLC)is still in the early stage of research due to its two strict and conflicting requirements,i.e.,ultra-low latency and ultra-high reliability,and its impact on security performance is still unclear.Specifically,short-packet communication is expected to meet the delay requirement of URLLC,while the degradation of reliability caused by it makes traditional physical-layer security metrics not applicable.In this paper,we investigate the secure short-packet transmission in uplink massive multiuser multiple-inputmultiple-output(MU-MIMO)system under imperfect channel state information(CSI).We propose an artificial noise scheme to improve the security performance of the system and use the system average secrecy throughput(AST)as the analysis metric.We derive the approximate closed-form expression of the system AST and further analyze the system asymptotic performance in two regimes.Furthermore,a one-dimensional search method is used to optimize the maximum system AST for a given pilot length.Numerical results verify the correctness of theoretical analysis,and show that there are some parameters that affect the tradeoff between security and latency.Moreover,appropriately increasing the number of antennas at the base station(BS)and transmission power at user devices(UDs)can increase the system AST to achieve the required threshold.
基金Natural Science Foun-dation of China(No.62171464,61801496 and 61771487)This paper was presented in part at the 2021 IEEE International Conference on Communica-tions Workshops(ICC Workshops),2021.
文摘Cognitive Internet of Things(IoT)has at-tracted much attention due to its high spectrum uti-lization.However,potential security of the short-packet communications in cognitive IoT becomes an important issue.This paper proposes a relay-assisted maximum ratio combining/zero forcing beamforming(MRC/ZFB)scheme to guarantee the secrecy perfor-mance of dual-hop short-packet communications in cognitive IoT.This paper analyzes the average secrecy throughput of the system and further investigates two asymptotic scenarios with the high signal-to-noise ra-tio(SNR)regime and the infinite blocklength.In ad-dition,the Fibonacci-based alternating optimization method is adopted to jointly optimize the spectrum sensing blocklength and transmission blocklength to maximize the average secrecy throughput.The nu-merical results verify the impact of the system pa-rameters on the tradeoff between the spectrum sensing blocklength and transmission blocklength under a se-crecy constraint.It is shown that the proposed scheme achieves better secrecy performance than other bench-mark schemes.
文摘极端天气事件的发生会导致电力负荷产生突增或突降,对电网的稳定性和供电能力带来挑战。然而,现有的超短期负荷预测方法对极端天气下非线性和动态变化的负荷特征预测能力有限。为应对极端天气下负荷突变性强及波动剧烈导致的预测精度降低的问题,提出了一种考虑极端天气的二次重构分解去噪和双向长短时记忆网络(bidirectional long short-term memory,BiLSTM)的超短期电力负荷预测方法。首先,利用最大信息系数选取出能够最大程度反映对负荷影响的气候特征。然后,通过二次重构分解去噪方法提取到负荷多个频段的特征,降低数据复杂性,为BiLSTM模型提供更干净和信息量更清晰的输入序列,从而改善模型的训练效果和预测能力。最后基于比利时、福建省某区域以及得土安市的历史数据集进行算例分析,不同算例中平均绝对百分比误差分别下降到1.024%、0.875%、1.270%和1.009%,实验结果验证了所提方法在极端天气发生时的电力负荷超短期预测方面具有较好的预测性能和广阔的应用前景。
