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China Communications 2024年第2期21卷 17-31页

作者： Shaojing Wang Xiaomei Tang Jing Lei chunjiang ma Chao Wen Guangfu Sun School of Electronic Science National University of Defense TechnologyChangsha 410073China

Orthogonal Time Frequency and Space(OTFS) modulation is expected to provide high-speed and ultra-reliable communications for emerging mobile applications, including low-orbit satellite communications. Using the Doppler frequency for positioning is a promising research direction on communication and navigation integration. To tackle the high Doppler frequency and low signal-to-noise ratio(SNR) in satellite communication, this paper proposes a Red and Blue Frequency Shift Discriminator(RBFSD) based on the pseudo-noise(PN) *** paper derives that the cross-correlation function on the Doppler domain exhibits the characteristic of a Sinc function. Therefore, it applies modulation onto the Delay-Doppler domain using PN sequence and adjusts Doppler frequency estimation by red-shifting or blue-shifting. Simulation results show that the performance of Doppler frequency estimation is close to the Cramér-Rao Lower Bound when the SNR is greater than -15dB. The proposed algorithm is about 1/D times less complex than the existing PN pilot sequence algorithm, where D is the resolution of the fractional Doppler.

关键词： channel estimation communication and navigation integration Orthogonal Time Frequency and Space pseudo-noise sequence red-blue frequency shift discriminator

一种基于功率可行域的卫星导航欺骗干扰评估方法

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武汉大学学报（信息科学版） 2023年第7期48卷 1160-1169页

作者：唐小妹马鹏程马春江国防科技大学电子科学学院湖南长沙410073

针对欺骗干扰评估场景复杂、反欺骗策略繁多等所导致的量化评估难度大的问题,建立了欺骗对抗场景到欺骗对抗效果的评估模型和映射过程,并从欺骗对抗场景中的功率空间和欺骗对抗效果中的欺骗有效概率出发,设计了基于欺骗有效功率可行域... 详细信息

针对欺骗干扰评估场景复杂、反欺骗策略繁多等所导致的量化评估难度大的问题,建立了欺骗对抗场景到欺骗对抗效果的评估模型和映射过程,并从欺骗对抗场景中的功率空间和欺骗对抗效果中的欺骗有效概率出发,设计了基于欺骗有效功率可行域的评估方法与指标。仿真结果表明,该评估方法可以实现不同反欺骗策略之间性能的量化对比,能够为接收机反欺骗算法选择和优化提供量化评估方法。

关键词：卫星导航欺骗干扰功率空间干扰评估导航接收机

GNSS Carrier Tracking via a Variational Bayesian Adaptive Kalman Filter for High Dynamic Conditions

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GNSS Carrier Tracking via a Variational Bayesian Adaptive Ka...

A Method of Carrier Phase Multipath Mitigation Based on Punctual Code Correlation Reference Waveform

第十四届中国卫星导航年会

作者： Song Li chunjiang ma Pengcheng ma Honglei Lin Xiaomei Tang Feixue Wang National University of Defense Technology

Under high dynamic conditions,a robust carrier tracking approach is essential for global navigation satellite system(GNSS) *** this paper,the powerful Kalman filter(KF) technique is adopted in GNSS carrier *** correlation signals are used as system measurements to discard the discriminator restricted by linear ***,a linear measurement equation is established based on the error-state,so that the system model is *** the KF can be used instead of the nonlinear KF which requires more computational ***,to exploit the potential of the KF under different conditions,an adaptive KF(AKF) based on the variational Bayesian approach is *** proposed filter has accurate and robust estimation performance,especially under high dynamic *** results verify the applicability of the proposed system model and the superiority of the proposed filter compared with the traditional KF and existing AKFs.

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A Method of Carrier Phase Multipath Mitigation Based on Punc...

Cross-Correlation based Spreading Code Authentication Scheme for Civil GNSS Signals

第九届中国卫星导航学术年会

作者： chunjiang ma Xiaomei Tang Yingxiang Liu Zhibin Xiao Guangfu Sun College of Electronic Science National University of Defense Technology

Carrier phase multipath is one of the main sources of error for high-precision GNSS applications. In an urban environment with severe multipath fading, multipath effects can cause centimeter-scale shifts in carrier phase measurements. The carrier multipath is related to the location of the receiver, the variation of static multipath error is mainly affected by the satellite motion, showing the deviation characteristic, which is difficult to eliminate by using the existing differential technique or multipath error model. This paper defines the concept of carrier multipath peak-to-peak ratio in carrier correlator and uses it to measure the effect of multipath signal on carrier phase measurement. Considered the characteristics that multipath signals always lag behind direct signals, this paper presents a method of reference waveform design for on-time codes. The asymmetric cross-correlation function constructed by this method can suppress the cross-correlation of lag signals and improve the anti-carrier phase multipath capability. Through theoretical analysis and simulation, the proposed method of carrier phase multipath reduction can reduce the envelope area of carrier phase multipath error by about 49% when the gate width of the reference waveform is 1/4 chip, effectively increasing the receiver carrier multipath rejection.

关键词： Carrier Phase Multipath Peak to Peak Ratio Code Reference Waveform GNSS

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Cross-Correlation based Spreading Code Authentication Scheme...

Simulation on Mechanical Behaviors of Oil-film Bearing Sleeve by Elastic Interference Fit

第十三届中国卫星导航年会

作者： Muzi Yuan Xiaomei Tang Shengqiang Lou chunjiang ma Gang Ou National University of Defense Technology

Navigation signal authentication schemes are effective methods to protect civilian receivers against spoofing attacks by providing unforgeable information to verify the authenticity of signals. In this paper Cross-Correlation based Spreading Code Authentication, or CC-SCA, is proposed to authenticate GNSS civilian signals at high time resolution with small storage requirement. CC-SCA employs a cryptographically generated authentication spreading code punctured into public spreading code in civilian signals. Since initial code phases of authentication spreading code are different and derived from security code, a correlation peak can be detected and authenticated in the cross-correlation between baseband signals of different satellites. According to this principle, signal structure and authenticable receiver architecture are proposed while performance metrics and the selection of parameters are analysed. Finally, this scheme is demonstrated with a specific implementation and parameter selection for Beidou B1 C civilian signals.

关键词： Navigation signal authentication Spreading code authentication Cross-correlation Authentication implementation

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武汉理工大学学报 2006年第S1期28卷 173-176页

作者： HUANG Qingxue1,WANG Jianmei 1,2 ,ZHAO chunjiang1,ma Lifeng2 (1.Taiyuan University of Science and Technology,Taiyuan 030024,China 2.Taiyuan University of Technology,Taiyuan 030024,China) Taiyuan University of Science and Technology Taiyuan 030024China Taiyuan University of Science and Technology Taiyuan 030024China Taiyuan University of Technology Taiyuan 030024China Taiyuan University of Technology Taiyuan 030024China

Oil film bearing,which works on thin film between sleeve and bush,is widely used in steel industry due to the characteristics of high efficiency and low noise,etc. The backup roll of 1 580PC hot strip mill invested by some steel corporation has been equipped with such bearing. During the process of setup&disassembly and usage period,the sleeve has been dramatically damaged,which results in production accidents and decreases its service life,thus heavily influencing steel production. Aimed at such puzzles,under specific loadcase,mechanical properties of bearing sleeve,as well as estimation of contact status and adhesive force of sleeve by interference fit,are quantitatively simulated by finite element method,which establishes an mechanical foundation for improving the load capacity of bearing and decreasing its wear and adhesion damages. Finally,some measures and conclusions are drawn.

关键词： oil-film bearing sleeve interference fit wear and adhesion damages

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永磁同步电机调速系统的伪微分反馈控制

电工技术学报 2010年第8期25卷 18-23页

作者：李光泉葛红娟刘天翔马春江南京航空航天大学自动化学院南京210016

永磁同步电机是一个多变量、非线性、强耦合的复杂系统,对外界扰动及内部参数变化敏感,为改善系统动静态性能,提高系统鲁棒性,本文引入了一种新的速度调节方法—伪微分反馈(Pseudo Derivative Feedback,PDF)控制策略。文章首先介绍了基... 详细信息

永磁同步电机是一个多变量、非线性、强耦合的复杂系统,对外界扰动及内部参数变化敏感,为改善系统动静态性能,提高系统鲁棒性,本文引入了一种新的速度调节方法—伪微分反馈(Pseudo Derivative Feedback,PDF)控制策略。文章首先介绍了基于PDF调节器的矩阵变换器?永磁同步电机调速系统,推导出了系统的传递函数和微分方程,根据推导结果绘制了系统的博德图,并对系统的动静态性能和抗干扰能力进行了理论分析。在同等条件下对两种调节器(PDF与PI)下的调速系统分别进行了仿真和实验研究,结果表明:采用PDF调节器时,系统的输出响应速度更快、无超调和振荡,有效地提高了系统的动静态性能和鲁棒性。

关键词：伪微分反馈控制速度调节 PI控制鲁棒性永磁同步电机

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送电线路建设过程中的注意事项

现代盐化工 2018年第2期45卷 102-103页

作者：马春江黑龙江省华龙送变电安装有限公司黑龙江哈尔滨150036

随着我国社会经济的发展,我国电力事业在迅速地发展,并且有着非常好的发展前景,促进我国经济的繁荣。在电力事业发展的同时,电力事故也频繁地发生,特别是送电线路中的问题。送电线路在建设的过程中存在很多不确定性的因素,受到环境等多... 详细信息

随着我国社会经济的发展,我国电力事业在迅速地发展,并且有着非常好的发展前景,促进我国经济的繁荣。在电力事业发展的同时,电力事故也频繁地发生,特别是送电线路中的问题。送电线路在建设的过程中存在很多不确定性的因素,受到环境等多个方面的干扰,给送电线路带来很大的困难和阻碍,严重情况下带来很大的经济损失。因此,加强对送电线路建设的研究,对其建设过程中的问题进行分析,采取有效的措施很有必要。文章对送电线路建设中的注意事项进行分析,以供参考。

关键词：送电线路建设过程注意事项

基于NELDER-MEAD的GNSS欺骗干扰参数估计方法

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信号处理 2022年第12期38卷 2606-2616页

作者：王佳奇孙广富唐小妹马春江马鹏程国防科技大学电子科学学院湖南长沙410073

欺骗干扰对关键领域的导航服务带来了重大挑战,因此有必要发展欺骗干扰监测系统,欺骗信号参数估计是欺骗干扰监测的重要组成部分。当欺骗信号的码相位与真实信号重叠时,无法采用多通道技术对真实信号和欺骗信号分别进行跟踪估计。本文... 详细信息

欺骗干扰对关键领域的导航服务带来了重大挑战,因此有必要发展欺骗干扰监测系统,欺骗信号参数估计是欺骗干扰监测的重要组成部分。当欺骗信号的码相位与真实信号重叠时,无法采用多通道技术对真实信号和欺骗信号分别进行跟踪估计。本文通过分析小时延场景下的信号参数空间,引入导航信号相关峰形状、宽度等先验信息,提出了一种基于NELDER-MEAD的欺骗信号参数估计方法,利用NELDER-MEAD算法直接搜索信号的码相位,在此基础上采用最小二乘法对功率和载波相位进行估计,能够在减小计算量的同时准确估计出欺骗信号与真实信号的参数。仿真结果表明,本文方法的相关域搜索次数比传统MLE方法降低了90%以上。最后通过无线测试,验证了该方法在实际场景中的有效性。

关键词：全球卫星导航系统欺骗干扰欺骗监测参数估计相关函数

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Zn对Mg-9Al合金凝固行为的影响

特种铸造及有色合金 2002年第5期22卷 8-10页

作者：王业双马春江朱燕萍丁文江上海交通大学

研究了Zn元素对Mg 9Al合金的凝固行为 ,尤其是对热裂倾向性的影响。通过热分析手段考察合金的凝固特征。用热裂环法评价合金的热裂倾向性 ,引入了热裂倾向性 (HSC)因子的概念。并通过金相观察、扫描电镜和电子探针对合金的凝固、热裂行... 详细信息

研究了Zn元素对Mg 9Al合金的凝固行为 ,尤其是对热裂倾向性的影响。通过热分析手段考察合金的凝固特征。用热裂环法评价合金的热裂倾向性 ,引入了热裂倾向性 (HSC)因子的概念。并通过金相观察、扫描电镜和电子探针对合金的凝固、热裂行为进行了研究。研究发现 ,在凝固过程中Zn ,Al元素由于晶间偏析而在晶界富集。Zn元素的加入 ,增加了晶界低熔点相的量 ,并降低了其熔点 ,从而明显增加了合金的热裂倾向性。Mg 9Al xZn合金的热裂产生于凝固后期 ,呈沿晶断裂。加入Zn元素对Mg

关键词： Mg-Al合金凝固热裂锌镁合金