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Multi-agent Based Hierarchy Simulation Models of Carrier-based Aircraft Catapult Launch 被引量:18
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作者 王维军 屈香菊 郭林亮 《Chinese Journal of Aeronautics》 SCIE EI CAS CSCD 2008年第3期223-231,共9页
With the aid of multi-agent based modeling approach to complex systems, the hierarchy simulation models of carrier-based aircraft catapult launch are developed. Ocean, carrier, aircraft, and atmosphere are treated as ... With the aid of multi-agent based modeling approach to complex systems, the hierarchy simulation models of carrier-based aircraft catapult launch are developed. Ocean, carrier, aircraft, and atmosphere are treated as aggregation agents, the detailed components like catapult, landing gears, and disturbances are considered as meta-agents, which belong to their aggregation agent. Thus, the model with two layers is formed i.e. the aggregation agent layer and the meta-agent layer. The information communication among all agents is described. The meta-agents within one aggregation agent communicate with each other directly by information sharing, but the meta-agents, which belong to different aggregation agents exchange their information through the aggregation layer first, and then perceive it from the sharing environment, that is the aggregation agent. Thus, not only the hierarchy model is built, but also the environment perceived by each agent is specified. Meanwhile, the problem of balancing the independency of agent and the resource consumption brought by real-time communication within multi-agent system (MAS) is resolved. Each agent involved in carrier-based aircraft catapult launch is depicted, with considering the interaction within disturbed atmospheric environment and multiple motion bodies including carrier, aircraft, and landing gears. The models of reactive agents among them are derived based on tensors, and the perceived messages and inner frameworks of each agent are characterized. Finally, some results of a simulation instance are given. The simulation and modeling of dynamic system based on multi-agent system is of benefit to express physical concepts and logical hierarchy clearly and precisely. The system model can easily draw in kinds of other agents to achieve a precise simulation of more complex system. This modeling technique makes the complex integral dynamic equations of multibodies decompose into parallel operations of single agent, and it is convenient to expand, maintain, and reuse the program codes. 展开更多
关键词 multi-agent system (MAS) multi-agent based modeling (MABM) TENSOR carrier-based aircraft catapult launch hierarchy simulation model
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CQI Feedback Compression Method for Multi-Carrier MIMO Transmission
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作者 李永杰 宋荣方 《China Communications》 SCIE CSCD 2011年第5期20-27,共8页
In multi-user wireless communication systems,adaptive modulation and scheduling are promising techniques for increasing system throughput.However,for multi-carrier systems,they will lead to overwhelming user feedback ... In multi-user wireless communication systems,adaptive modulation and scheduling are promising techniques for increasing system throughput.However,for multi-carrier systems,they will lead to overwhelming user feedback overhead for Channel Quality Indication(CQI) in every subcarrier.In our work,novel CQI feedback schemes are proposed based on the recently proposed theory of Compressive Sensing(CS).First,the standard CS method is introduced to reduce CQI feedback overhead for multi-carrier Multiple-Input Multiple-Output transmission.In addition,via further research on the design of measurement matrix with standard CS,a novel CQI feedback scheme based on subspace CS is proposed by exploiting the subspace information of the underlying signal and the feedback rate is greatly decreased.Simulation results show that,with the same feedback rate,the throughputs with subspace CS outperform the Discrete Cosine Transform(DCT)-based method which is usually employed,and the throughputs with standard CS outperform DCT when the feedback rate is larger than 0.13 bits/subcarrier. 展开更多
关键词 CQI multi-carrier feedback compression compressive sensing
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Multi-carrier transport in ZrTe_5 film
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作者 Fangdong Tang Peipei Wang +4 位作者 Peng Wang Yuan Gan Le Wang Wei Zhang Liyuan Zhang 《Chinese Physics B》 SCIE EI CAS CSCD 2018年第8期498-504,共7页
Single-layered zirconium pentatelluride (ZrTes) has been predicted to be a large-gap two-dimensional (2D) topolog- ical insulator, which has attracted particular attention in topological phase transitions and pote... Single-layered zirconium pentatelluride (ZrTes) has been predicted to be a large-gap two-dimensional (2D) topolog- ical insulator, which has attracted particular attention in topological phase transitions and potential device applications. Herein, we investigated the transport properties in ZrTe5 films as a function of thickness, ranging from a few nm to several hundred nm. We determined that the temperature of the resistivity anomaly peak (Tp) tends to increase as the thickness decreases. Moreover, at a critical thickness of ~ 40 rim, the dominating carriers in the films change from n-type to p-type. A comprehensive investigation of Shubnikov-de Hass (SdH) oscillations and Hall resistance at variable temperatures revealed a multi-carrier transport tendency in the thin films. We determined the carrier densities and mobilities of two majority car- riers using the simplified two-carrier model. The electron carriers can be attributed to the Dirac band with a non-trivial Berry phase ~, while the hole carriers may originate from surface chemical reaction or unintentional doping during the microfabrication process. It is necessary to encapsulate the ZrTe5 film in an inert or vacuum environment to potentially achieve a substantial improvement in device quality. 展开更多
关键词 multi-carrier transport ZrTe5 film thickness-dependence gate-dependence
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ICI elimination of M-band wavelet multi-carrier modulation system
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作者 彭章友 刘艳艳 张兴 《Journal of Shanghai University(English Edition)》 CAS 2010年第1期6-11,共6页
To solve the inter carrier interference (ICI) elimination problem of an M-band wavelet multi-carrier modulation system, this paper analyzes the principle of the ICI caused by the Doppler frequency shift and its math... To solve the inter carrier interference (ICI) elimination problem of an M-band wavelet multi-carrier modulation system, this paper analyzes the principle of the ICI caused by the Doppler frequency shift and its mathematical expression based on the M-band wavelet multi-carrier modulation system model. Through the analysis of the mathematical expression and combining with the perfect reconstruction conditions of the filter banks, we propose the design conditions of an M-band filter to reduce and eliminate the ICI. The impulse response model of the filter design conditions and an iterative algorithm is also established. The simulation results show that the proposed ICI reduction and elimination methods can effectively improve the system performance. 展开更多
关键词 M-band wavelet multi-carrier modulation Doppler frequency shift inter carrier interference (ICI) impulseresponse
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Factors affecting the performance of a multi-tone carrier source based re-circulating frequency shifter
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作者 席丽霞 李建平 +2 位作者 张晓光 田凤 张文博 《Chinese Physics B》 SCIE EI CAS CSCD 2011年第8期210-215,共6页
Generation of single-sideband (SSB) multi-carrier source based on a recirculating frequency shifter (RFS) is anal- ysed theoretically and realized experimentally. The effects of affecting factors originating from ... Generation of single-sideband (SSB) multi-carrier source based on a recirculating frequency shifter (RFS) is anal- ysed theoretically and realized experimentally. The effects of affecting factors originating from the deviation from the right operation bias voltage and unbalanced amplitude, and the phase of the radio frequency (RF) drive signals on the performance of the multi-tone source are discussed in detail. Based on the theoretical analysis, high-quality 50-tone out- put is successfully realized. Experiments under some implementation imperfections are also carried out. The imperfect and low-quality output results are in good agreement with theoretical analysis. 展开更多
关键词 multi-tone carrier source recirculating frequency shifter affecting factors
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On the Characteristic of Orthogonality for Multi-Carrier-Based Systems
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作者 Hao Wei Huang Joy Iong-Zong Chen Chi-Tsung Huang 《Engineering(科研)》 2013年第8期642-646,共5页
The dominate factors caused by reasons of losing the orthogonality in fading channel including FBC (fading branch correlation), CFO (carrier frequency offset), and even the CPN (carrier phase noise) are novel discussi... The dominate factors caused by reasons of losing the orthogonality in fading channel including FBC (fading branch correlation), CFO (carrier frequency offset), and even the CPN (carrier phase noise) are novel discussion in this letter. The first one factor causes the ISI (inter-symbol interference), and, however, the latter two will lead to the phenomenon of CPE (common phase error) and ICI (inter-carrier interference). On the other hand, they will lead to the loss of orthogonality for the radio system with multi-carrier modulating schemes, i.e., both them mainly deteriorate a wireless communication system. Eventually, in this letter not only the analytical expressions are derived, but a three dimension numerical results from the analysis involve the three parameters also illustrated is. 展开更多
关键词 CFO CPN FBC multi-carrier Modulating
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Spectrally Efficient Multi-Carrier Modulation Using Gabor Transform
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作者 Shravan Sriram Naveenkumar Vijayakumar +3 位作者 P. Aditya Kumar Akash S. Shetty V. P. Prasshanth K. A. Narayanankutty 《Wireless Engineering and Technology》 2013年第2期112-116,共5页
Non Orthogonal Frequency Division Multiplexing (NOFDM) systems make use of a transmission signal set which is not restricted to orthonormal bases unlike previous OFDM systems. The usage of non-orthogonal bases general... Non Orthogonal Frequency Division Multiplexing (NOFDM) systems make use of a transmission signal set which is not restricted to orthonormal bases unlike previous OFDM systems. The usage of non-orthogonal bases generally results in a trade-off between Bit Error Rate (BER) and receiver complexity. This paper studies the use of Gabor based on designing a Spectrally Efficient Multi-Carrier Modulation Scheme. Using Gabor Transform with a specific Gaussian envelope;we derive the expected BER-SNR performance. The spectral usage of such a NOFDM system when affected by a channel that imparts Additive White Gaussian Noise (AWGN) is estimated. We compare the obtained results with an OFDM system and observe that with comparable BER performance, this system gives a better spectral usage. The effect of window length on spectral usage is also analyzed. 展开更多
关键词 Non-Orthogonal FREQUENCY DIVISION multiPLEXING (NOFDM) Spectrally EFFICIENT FREQUENCY DIVISION multiPLEXING (SEFDM) GABOR Transform OFDM Reisz Bases multi carrier Modulation (MCM)
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基于multi-agent的多式联运各区段分运承运人选择系统 被引量:4
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作者 马彩雯 孙光圻 《上海海事大学学报》 北大核心 2006年第3期51-54,共4页
提出将agent技术应用于多式联运各区段承运人的选择,通过多agent之间的协商完成各区段分运承运人的科学选择.在系统开发实施方面,采用基于Java的agent框架,设计出基于multi-agent的多式联运各区段分运承运人选择系统结构,并给出各区段... 提出将agent技术应用于多式联运各区段承运人的选择,通过多agent之间的协商完成各区段分运承运人的科学选择.在系统开发实施方面,采用基于Java的agent框架,设计出基于multi-agent的多式联运各区段分运承运人选择系统结构,并给出各区段分运承运人选择的原型系统. 展开更多
关键词 多式联运 承运人 多AGENT系统 合同网协议
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A Sensor-less Surface Mounted PMSM for Electronic Speed Control in Multilevel Inverter
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作者 S.Dinesh Kumar A.Jagadeeshwaran 《Intelligent Automation & Soft Computing》 SCIE 2023年第5期2201-2215,共15页
Recent advancements in power electronics technology evolves inverter fed electric motors.Speed signals and rotor position are essential for controlling an electric motor accurately.In this paper,the sensorless speed c... Recent advancements in power electronics technology evolves inverter fed electric motors.Speed signals and rotor position are essential for controlling an electric motor accurately.In this paper,the sensorless speed control of surface-mounted permanent magnet synchronous motor(SPMSM)has been attempted.SPMSM wants a digital inverter for its precise working.Hence,this study incor-poratesfifteen level inverter to the SPMSM.A sliding mode observer(SMO)based sensorless speed control scheme is projected to determine rotor spot and speed of the multilevel inverter(MLI)fed SPMSM.MLI has been operated using a multi carrier pulse width modulation(MCPWM)strategy for generation offif-teen level voltages.The simulation works are executed with MATLAB/SIMU-LINK software.The steadiness and the heftiness of the projected model have been investigated under no loaded and loaded situations of SPMSM.Furthermore,the projected method can be adapted for electric vehicles. 展开更多
关键词 Surface-mounted permanent magnet synchronous motor sensorless speed control multilevel inverter torque estimation multi carrier pulse width modulation
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基于三频观测的Multi_GNSS载波相位特性分析
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作者 刘荟萃 鞠冰 +2 位作者 谭永政 曹建峰 李勰 《测绘与空间地理信息》 2023年第9期6-8,共3页
载波相位观测噪声和多径误差是衡量载波相位观测数据质量的重要指标。采用三频消电离层无几何组合对GPS、BDS和Galileo系统的载波相位观测噪声和多径误差进行计算。选取IGS ARHT和MGO2两测站2021年连续30 d的数据,对上述GNSS系统的载波... 载波相位观测噪声和多径误差是衡量载波相位观测数据质量的重要指标。采用三频消电离层无几何组合对GPS、BDS和Galileo系统的载波相位观测噪声和多径误差进行计算。选取IGS ARHT和MGO2两测站2021年连续30 d的数据,对上述GNSS系统的载波相位观测噪声和多径误差特性进行了分析,采用高阶谐函数对GPS Block IIF卫星的频间钟偏差进行模型化以降低其对DIF的影响,结论显示,各系统的DIF组合均方根值随着仰角的增大逐渐减小,在高仰角区间内比低仰角区间下降约90%;受残余IFCB的影响,GPS系统的DIF组合均方根值最大,约为BDS-2系统的3—7倍,约为BDS-3和GAL系统的20倍。 展开更多
关键词 GNSS 载波相位 观测噪声 多径误差 频间钟偏差
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Multi-h CPM解调算法研究综述 被引量:2
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作者 上官泽胤 《电子测量技术》 2019年第5期60-64,共5页
Multi-h CPM体制凭借着高效的带宽效率和功率效率,在未来航天遥测领域具有巨大的潜在优势,但是解调技术的高复杂度限制了其广泛应用。为了能在较小性能损失的前提下实现解调结构的简化,在对Multi-h CPM体制的特点和发展现状进行了简要... Multi-h CPM体制凭借着高效的带宽效率和功率效率,在未来航天遥测领域具有巨大的潜在优势,但是解调技术的高复杂度限制了其广泛应用。为了能在较小性能损失的前提下实现解调结构的简化,在对Multi-h CPM体制的特点和发展现状进行了简要介绍之后,重点阐述了Multi-h CPM信号的接收机的基本结构,详细总结了其中的载波同步、定时同步、调制指数同步以及序列检测技术的方法来源、发展历程和理论基础,分析了各自的优缺点,最后,提出了Multi-h CPM体制的进一步研究方向。 展开更多
关键词 multi-h CPM 解调 载波同步 定时同步 调制指数同步 序列检测
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Evaluation of multi-cycle performance of chemical looping dry reforming using CO_2 as an oxidant with Fe–Ni bimetallic oxides 被引量:6
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作者 Zhen Huang Huanqi Jiang +7 位作者 Fang He Dezhen Chen Guoqiang Wei Kun Zhao Anqing Zheng Yipeng Feng Zengli Zhao Haibin Li 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2016年第1期62-70,共9页
Chemical looping dry reforming(CLDR) is an innovative technology for CO2 utilization using the chemical looping principle.The CLDR process consists of three stages,i.e.CH4 reduction,CO2 reforming,and air oxidation.S... Chemical looping dry reforming(CLDR) is an innovative technology for CO2 utilization using the chemical looping principle.The CLDR process consists of three stages,i.e.CH4 reduction,CO2 reforming,and air oxidation.Spinel nickel ferrite(NiFe2O4) was prepared and its multi-cycle performance as an oxygen carrier for CLDR was experimentally investigated.X-ray diffraction(XRD) and Laser Raman spectroscopy showed that a pure spinel crystalline phase(NiFe2O4) was obtained by a parallel flow co-precipitating method.NiFe2O4was reduced into Fe-Ni alloy and wustite(FexO) during the CH4 reduction process.Subsequent oxidation of the reduced oxygen carrier was performed with CO2 as an oxidant to form an intermediate state:a mixture of spinel Ni(1-x)Fe(2+x)O4,Fe(2+y)O4 and metallic Ni.And CO was generated in parallel during this stage.Approximate 185 mL of CO was generated for 1 g spinel NiFe2O4 in a single cycle.The intermediate oxygen carrier was fully oxidized in the air oxidation stage to form a mixture of Ni(1+x)Fe(2-x)O4 and Fe2O3.Although the original state of oxygen carrier(NiFe2O4) was not fully regenerated and agglomeration was observed,a good recyclability was shown in 10 successive redox cycles. 展开更多
关键词 Chemical looping Oxygen carrier Nickel ferrite CO2 utilization multi-cycle performance
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Novel scheme of high precision inertial measurement for high-speed rotating carriers 被引量:1
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作者 武庆雅 贾庆忠 +1 位作者 单家元 孟秀云 《Journal of Beijing Institute of Technology》 EI CAS 2015年第2期151-157,共7页
In order to satisfy the requirement of high precision measurement in a high dynamic environment, a kind of gyro aided multi-accelerometer inertial measurement unit (GAMA-IMU) with six accelerometers and two gyros (... In order to satisfy the requirement of high precision measurement in a high dynamic environment, a kind of gyro aided multi-accelerometer inertial measurement unit (GAMA-IMU) with six accelerometers and two gyros (6A2G) was proposed in this paper. The available configurations have the problem of low measurement precision In a high dynamic environment due to channel coupling. The three channels were decoupled when calculating the angular velocity in the proposed configuration. The yawing and pitching angular velocity were directly measured by gyros, while only the rolling angular velocity was obtained by the GAMA-IMU indirectly from the rolling angular acceleration and quadratic component of rolling angular velocity. Then a single channel rolling angular velocity calculation model was established and the extended Kalman filter (EKF) was used to do state esti- mation. Simulations were carried out and results indicated that the calculation precision of the proposed 6A2G configuration could meet the demand of high precision measurement for a high-speed rotating carrier. 展开更多
关键词 high-speed rotating carrier gyro aided multi-accelerometer angular velocity calcula- tion extended kaiman filter (EKF)
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基于可微分架构搜索的多载波信号自动调制识别
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作者 李杰 李靖 +1 位作者 吕璐 宫丰奎 《通信学报》 EI CSCD 北大核心 2024年第9期14-25,共12页
针对城市多径信道下缺乏多载波信号通用数据集,以及传统信号特征与网络模型难以有效识别低信噪比下失真信号调制类型的问题,提出一种基于可微分架构搜索的多载波信号自动调制识别算法。首先,产生了常见OFDM、FBMC与OTFS多载波信号经过... 针对城市多径信道下缺乏多载波信号通用数据集,以及传统信号特征与网络模型难以有效识别低信噪比下失真信号调制类型的问题,提出一种基于可微分架构搜索的多载波信号自动调制识别算法。首先,产生了常见OFDM、FBMC与OTFS多载波信号经过典型城市多径信道的接收信号数据集,选取对调制参数不敏感的信号时频图作为特征向量来训练神经网络;其次,采用可微分架构搜索方法自动搜索最佳网络结构,避免了网络结构设计的反复验证工作;最后,在特征学习过程中引入联合注意力机制,将失真信号特征进行空间转换以降低多径干扰影响,同时计算特征图各通道信息权重并排序,以提升相关特征图通道的分类效果。仿真结果表明,所提算法不仅能提升在城市多径信道环境下尤其是低信噪比时的识别正确率,而且对调制参数变化和小样本场景具有更好的鲁棒性。 展开更多
关键词 可微分架构搜索 多载波信号 自动调制识别 城市多径信道 联合注意力机制
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基于滤波器组多载波的组网低截获探通一体化信号设计
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作者 陈军 王昊 +2 位作者 贺晓波 王杰 周建江 《电子与信息学报》 EI CAS CSCD 北大核心 2024年第11期4268-4277,共10页
在现代电子对抗中,将多部探通一体化系统进行组网,可以提高单站探通一体化系统探测效率和协同探测能力。由于探通一体化信号自身峰均比较高,信号易被截获,系统的生存能力受到严重威胁。为了提升探通一体化信号的低截获性能(LPI),首先该... 在现代电子对抗中,将多部探通一体化系统进行组网,可以提高单站探通一体化系统探测效率和协同探测能力。由于探通一体化信号自身峰均比较高,信号易被截获,系统的生存能力受到严重威胁。为了提升探通一体化信号的低截获性能(LPI),首先该文在滤波器组多载波的框架下,提出一种通信子载波分组功率优化和雷达子载波异置等功率优化的组网低截获探通一体化信号时频结构。然后,该文从信息论的角度出发,统一了系统的性能评估指标;将最小化截获信息距离作为优化目标函数,建立了组网探通一体化信号低截获优化模型。该文将此优化模型转换为凸优化问题,并利用Karush-Kuhn-Tucker条件对其进行求解。仿真结果表明,该文所设计的组网低截获探通一体化信号在探测动目标时,节点间雷达干扰低至近–60 dB,通信误码率满足10^(–6)数量级,同时能有效降低截获信号的信噪比。 展开更多
关键词 低截获概率 探通一体化 组网系统 滤波器组多载波 信息论
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UFMC系统中基于阈值的改进DFT信道估计算法
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作者 陈雷 郝玉莲 +1 位作者 刘帅奇 张锁良 《计算机仿真》 2024年第5期338-342,414,共6页
针对通用滤波多载波(Universal Filtered Multi-Carrier,UFMC)系统中传统的基于离散傅里叶变换(Discrete Fourier Transform,DFT)的信道估计算法存在噪声区间不连续、信道长度内噪声消除不彻底、信号经DFT运算后频谱泄露高等问题,提出... 针对通用滤波多载波(Universal Filtered Multi-Carrier,UFMC)系统中传统的基于离散傅里叶变换(Discrete Fourier Transform,DFT)的信道估计算法存在噪声区间不连续、信道长度内噪声消除不彻底、信号经DFT运算后频谱泄露高等问题,提出一种基于阈值的改进DFT信道估计算法。算法在频域通过加窗以降低信道冲激响应(Channel Impulse Response,CIR)能量泄露,在时域通过设置阈值和指数平滑可最大限度滤除样本内噪声。理论分析与仿真结果表明,与传统的DFT估计算法相比,所提算法误比特率(Bit Error Ratio,BER)更低,在高信噪比下有1.5 dB左右的性能提升,能够进一步减少噪声对系统性能的影响,可有效提高信道估计的准确度。 展开更多
关键词 通用滤波多载波 离散傅里叶变换 信道冲激响应 阈值 指数平滑
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基于多载波阵的定域调制技术
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作者 徐友根 张译文 《北京理工大学学报》 EI CAS CSCD 北大核心 2024年第1期102-110,共9页
基于多载波阵,可以进行定位调制,实现信息的定向和定距传输,误码率仅在指定位置处出现零陷,从而提高物理层通信的安全性.但当指定位置与接收位置存在失配时,信号接收性能会明显下降。在定位调制技术的基础上,提出一种对位置误差不甚敏... 基于多载波阵,可以进行定位调制,实现信息的定向和定距传输,误码率仅在指定位置处出现零陷,从而提高物理层通信的安全性.但当指定位置与接收位置存在失配时,信号接收性能会明显下降。在定位调制技术的基础上,提出一种对位置误差不甚敏感的定域调制技术,其信息传输误码率的零陷宽度可在一定范围内进行调整,从而可在通信安全性和鲁棒性之间进行适当的折衷.将一维伍德沃德-劳森综合法推广为二维,以实现角度-距离二维平顶方向图的综合,将发射信号能量聚焦在预先设定的角度和距离区域内;构造伍德沃德-劳森综合法中所选角度和距离所对应的多载波阵流形矢量;在上述多载波阵流形矢量所张成空间的正交补空间中随机选择一个矢量,进行非信号能量聚焦区域的加密.仿真结果表明,所提定域调制方法可保证在整个预先设定的角度和距离区域内都具有较好的信号接收性能. 展开更多
关键词 多载波阵 定向调制 波束方向图综合 鲁棒
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反向散射中基于载波索引的混合NOMA方案
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作者 李世宝 陆锐 《无线电工程》 2024年第1期41-46,共6页
基于功率域非正交多址的环境反向散射通信系统上行链路常通过距离差完成用户配对。无源反向散射系统的双重信道衰落,导致远端边缘设备无法满足通信所需功率或解码所需信干噪比(Signal-to-Interference-Noise Ratio,SINR)约束。为了解决... 基于功率域非正交多址的环境反向散射通信系统上行链路常通过距离差完成用户配对。无源反向散射系统的双重信道衰落,导致远端边缘设备无法满足通信所需功率或解码所需信干噪比(Signal-to-Interference-Noise Ratio,SINR)约束。为了解决上述问题,提出一种OFDM和具有索引调制(Index Modulation,IM)的OFDM混合的上行NOMA方案,该方案由标签调制方案和反射系数调节方案组成。OFDM-IM提供了更好的能量效率,可以使功率水平低的设备满足通信条件。反向散射设备(Backscatter Devices,BD)根据接收到的功率水平,灵活地选择OFDM或者OFDM-IM,并在功率域叠加;通过调节反射系数保证叠加信号的功率差,接收机利用功率电平来执行多用户检测。实验结果表明,该方能够有效地提高远端用户解码的成功率,并且解码用户数量的增加提高了系统容量。 展开更多
关键词 反向散射 非正交多址接入 索引调制 多载波
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室内VLC-WiFi异构网络中多色载波资源分配
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作者 陈勇 张薇薇 +1 位作者 刘焕淋 陈金林 《聊城大学学报(自然科学版)》 2024年第5期48-59,共12页
可见光通信接入点(VLC AP)在室内密集部署的方式在扩大VLC-WiFi系统容量的同时,增加了覆盖的小区间干扰。为了降低小区间干扰,提高系统的吞吐量和平均用户满意度,本文设计了多色载波分配与功率控制(MCAPC)的资源分配方法。该方法依据VLC... 可见光通信接入点(VLC AP)在室内密集部署的方式在扩大VLC-WiFi系统容量的同时,增加了覆盖的小区间干扰。为了降低小区间干扰,提高系统的吞吐量和平均用户满意度,本文设计了多色载波分配与功率控制(MCAPC)的资源分配方法。该方法依据VLC AP的部署位置和信道特性,采用软频率复用方法确定各VLC AP的无干扰的主载波和多色副载波,并设计基于匹配博弈的载波和子频带分配算法为用户分配异构网络的频带资源;最后,设计基于功率控制效用值的干扰抑制的载波功率控制算法进一步抑制小区间干扰。研究结果表明,所提MCAPC方法能够提高室内多色VLC-WiFi异构网的系统吞吐量和用户的平均满意度。 展开更多
关键词 异构网络 小区间干扰 多色载波 功率控制 系统吞吐量
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多源视频数据驱动的舰面保障作业三维重建
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作者 徐明亮 王政 +1 位作者 王华 鲁爱国 《计算机辅助设计与图形学学报》 EI CSCD 北大核心 2024年第3期357-367,共11页
针对现有公开的航母舰面保障作业视频数据碎片化、相机角度多变、像素质量低下等问题,提出一种多源视频数据驱动的舰面保障作业三维重建方法.该方法首先对视频中对象轨迹方向进行预测,并采用联合外观和方向相似度的跟踪方法实现视频数... 针对现有公开的航母舰面保障作业视频数据碎片化、相机角度多变、像素质量低下等问题,提出一种多源视频数据驱动的舰面保障作业三维重建方法.该方法首先对视频中对象轨迹方向进行预测,并采用联合外观和方向相似度的跟踪方法实现视频数据的多目标轨迹跟踪;然后基于跟踪结果,依次采用相似度关联、特征轨迹分割、轨迹聚类提取多源数据中的保障作业对象并进行关联与融合;最后对融合得到的轨迹进行逼真三维重建.在MOT20数据集和舰面保障作业公开视频数据上,实验和用户调研数据的t检验结果表明,采用所提方法有99.5%的把握得到可信的舰面保障作业三维重建效果. 展开更多
关键词 舰面保障作业 多目标轨迹跟踪 轨迹关联与融合 三维重建
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